Warding Off Holiday Weight Gain 2.0: The Anti-Diabesity Effect of Coffee Goes Beyond its Caffeine Content.

Image 1: If they are not laden with pesticides and anti-fungals, the small brown beans from the coffee pant can easily compete with green, black oolong and pu-erh teas, when it comes to countering the unwanted side-effects of the "holiday diet"

Back in the days, both, tea and coffee were luxury goods and people felt privileged if they could have any of them. Today, they have become another of the endless commodities of our convenience society, where coffee, the former drink of the kings (and popes), has gotten a bad rep lately as being the underlying cause of the "adrenal burnout" that has befallen 90% of the visitors of pertinent Internet bulletin boards. I was thusly not surprised that SuppVersity student Fat Free commented yesterday's blogpost on the anti-obesity effects of tea rather sheepishly. As if his wish for "a coffee" on the list of the anti-holiday-weight-gain items was some atrocious act in the sense that "a coffee" could never be as healthy as a hip green tea. I mean wasn't it bad enough that the "holy" green tea was outperformed by its primitive black brother?

Well, guess what, dear green tea connoisseurs, it may well be that (organic) coffee beans are in no way inferior to the unquestionably healthy, yet recently slightly over-hyped unoxidized camellia sinensis leaves. At least this is what a soon to be published study by Yuji Matsuda and his colleagues from the Nagoja University in Japan would suggest (Matsuda. 2011).

Tea or coffee during the holiday season - only a matter taste?

Matsuda et al. put a group of 8-week old mice on a pro-diabetic high-fat diet (this is the type of "high fat diet" that is high both in fat and in carbs and thusly is a perfect image of what 75% of the people are "eating" in the holiday season ;-). In the course of the 17-week study period the mice received either regular drinking water, or 2.5x diluted coffee, or water that was laced with 200mg of caffeine per liter (with a water intake of 13-14g/100g BW this would translate to a daily dose of 2.8mg/100mg and a human equivalent of 2.3mg/kg, or 182mg of caffeine per day for an 80kg human being). The intention was to investigate whether the results of epidemiological studies by van Dam (2002; 2005), Huxley (2009) and Goto (2011), which suggest that regular coffee consumption is associated with a profoundly reduced risk of developing metabolic syndrome or type II diabetes, could be replicated in a laboratory setting.

Figure 1: Body weight at the beginning and end of the study period in the control group and the mice receiving 2.5x dilluted coffee or 200mg/L caffeine in their drinking water; food intake in g per 100g of  body weight (data adapted from Matsuda. 2011).

If you look at the weight changes of the animals in figure 1, it becomes evident that despite a (non significantly) greater food intake esp. in the "real coffee" group, the mice on the coffee or caffeine supplemented high-fat diets gained approx. 8% less body weight than their water guzzling peers.

Figure 2: Fat weight in mice after 17 weeks on high fat diet with either water, 2.5x diluted coffee or water + 200mg caffeine per L (data adapted from Matsuda. 2011).

Now while the intrinsically flawed concept of a "body mass index" that is still propagated by mainstream media would suggest that there is something like an "ideal body weight", the numbers on your scale, alone, have no predictive value in terms of future health risk. The reductions in visceral (epididymal fat) and subcatenous fat accumulation in the mice of the coffee and caffeine arm is thusly a considerably more important finding of this study than the slightly reduced weight gain. After all, the amount of visceral (=inter-organ) fat you are carrying around is one of the few relatively reliable indicators of whether you are going to see your grand-children graduate, or not.

Time and again: Whole foods, or drinks, outperform extracts

If you take a closer look you will notice that despite a general tendency towards lower body fat levels in the coffee and caffeine group, the "whole food", or I should say, "whole beverage" has a much more pronounced effect on the "bad" visceral (epididymal) fat depots. So, just in case you still like your pills, caps and powders: This is only the latest in a long line of foods (this is the stuff that is not sold in caps or powder form) with verified health benefits, where one isolated compound, of which we believe that it is the "active ingredient" turns less potent than the whole food - so, could it possibly be that Nature knows best?

Figure 3: Reductions in inflammatory cytokine (MCP-1, TNF-alpha, IL-6) and adipokine expression in the epididymal fat pads of mice receiving 2.5x diluted coffee or water laced with 200mg/L caffeine in addition to their high fat diet (data calculated based on Matsuda. 2011).

The "whole foods" vs. "extract" difference is also evident in the differential effects coffee and caffeine had the expression of the inflammatory cytokines MCP-1, TNF-Alpha and IL-6 and the adipokines adiponectin and leptin. With a more pronounced expression of the latter (leptin) and an almost identical expression of the former (adiponectin) indicating an improved visceral fat metabolism in the epididymal fat pads of the "coffee-drinking" mice.

Figure 4: Insulin response (area under the curve in mg * min / dl) during glucose tolerance at different time-points during the 17-week study period (data calculated based on Matsuda. 2011).

As the areas under the insulin response curve in the glucose tolerance test go to show. Coffee (=whole food!) consumption does also reduce the transient caffeine induced decrease in insulin sensitivity that has been touted as one of the reasons why coffee would be "bad" for you. As the data from the study goes to show, this effect is only temporary, even for plain caffeine and should not be an issue for the habitual coffee drinker. Moreover, the long term benefits totally outweigh any short term increases in fasting blood glucose (approx. +8% in the first weeks of the study) - or, getting back to the initial research hypothesis: Coffee consumption is a possible way to reduce the risk of developing type II diabetes (at least  for mice ;-)

Coffee or tea? The choice is up to thee!

Since a direct comparison of the data from yesterday's tea study on teas would not be valid, anyways, and because I do not want to disturb the pre-Chrismas harmony and provoke a war between coffee and tea drinkers in the comment area of this blogpost, I would just advice everyone to just decline the soda your relatives may be offering you over the holidays and stick to either tea or coffee... whatever you like better - and by the way, dehydration is neither an issue for the habitual tea nor the habitual coffee drinker (Grandjean. 2000)!

Green, Oolong, Pu'Erh or Black, All Teas May Help Keep Fat in Check. 750ml of Tea Per Day Could Ward Off Some of Your Holiday Weight Gain.

Image 1: Though color does matter to some extend, the most important thing appears to be that you drink your tea, whether it is green, black, white or well... pu-erh ;-)

Christmas time is approaching and my personal experience tells me that for many of my fellow human beings Santa has more than just iPads, iPhones and iPods in his gunnysack. The two, three or more pounds of body weight, Santa, or rather the festivities in his honor (unfortunately most people have forgotten that we are actually celebrating the birth of Jesus Christ) leave behind on their hips are yet mostly unwanted, so that the results of a recent study which was conducted by scientists from the National Hsinchu University of Education and the National Taiwan University may come pretty handy (Huang. 2011), especially for those of you who plan on having some "healthy" low sugar, but high fructose junk-food over the holidays.

Tea in lieu of hot wine punch could ward off your holiday weight gain 

In their 12-week study, Hsiu-Chen Huang and Jen-Kun Lin fed a group of initially healthy five-weeks-old male wistar rats (body weight: 150-200g) either a standard rat chow (Purina, Ralston Purina, St. Louis, MO) or a chow that consisted of 60% fructose and 40% of the chow.  Now, the latter group was again divided into a fructose control group and 4 experimental groups, where 4% of the standard chow were replaced by ground green, oolong, black or pu-erh tea leaves.

Figure 1: Catechin content of the leaves of green, oolong, black and pu-erh tea.

The scientists' reasoning was that the addition of the catechin-rich tea leaves (cf. figure 1) to the chow would ameliorate the detrimental effects of the high-fructose diets on blood lipids and other measures of metabolic health. Now, the whole rodent vs. human data aside, you are probably not willing to eat tea leaves, are you?

If we do yet assume that the main effect is induced by the "active ingredients" of the leaves and take the catechin content as a measure of how much of that we would have to ingest, eating the whole leaves is probably not even necessary. With their daily food intake of ~27.5g the rodents got roughly 46mg of catechins (calculated for the green tea).

That in turn would equal a dose of 153mg/kg (this calculation takes the weight gain into account) for the rats and 25mg/kg for a human being (cf. my article on human equivalent doses). So, if you weighed 80kg you would have to get 2g of catechins, which is the equivalent of 7.5 mini-cups of 100ml tea each brewed from 1g of tea (the last step in this calculation is based on USDA data from 2007).

Figure 2: Body weight of rats fed either the 40% fructose diet or the same diet enriched with 4% of tea leaves from green, black, oolong or pu-erh tea (data adapted from Huang. 2011)

But let's forget the math and the speculations about whether or not the results are going to translate to human beings for a moment and just have a look at the ameliorative effect the different types of tea had on the weight gain of the high fructose fed rats in the course of the study period. In that, it was not the catechin-laden green tea which had the most profound anti-obesity effect, but the highly oxidized black and the oxidized and fermented pu-erh teas.

Gaining the least weight does not necessarily mean having the "best" blood lipids

Interestingly, a different picture emerges, when we focus exclusively on the blood lipids, where the green tea leaves produce a lipid profile of which current medical "wisdom" tells us that it is the "most beneficial" one ;-)

Figure 3: Relative changes in serum lipid levels due to fructose feeding and fructose + tea leave feeding (data calculated based on Huang. 2011)

As a studious student of the SuppVersity, you will probably already be thinking about possible underlying mechanisms of these anti-obesity and anti-hyperlipidemic effects of the different types of tea leaves. Well, part of those are probably mediated by an old acquaintance: 5' AMP-activated protein kinase or AMPK.

Figure 4: Relative changes in AMPK phosphorylation and fatty acid synthethase in rats in response to feeding with 4% of black, green, oolon or pu-erh tea; my quantification on the left, original blots on the right  (data calculated based on Huang. 2011)

In view of the fact that Huang and Lin were either to lazy or did not consider it necessary to quantify their immunoblots (figure 4, right), I used a standard image processor to come up with the data in figure 4. Since this is obviously not very reliable, I also included the original blots so that you can convince yourselves that both the increase in AMPK phosphorylation, as well as the amelioration of the fructose induced increases in fatty acid synthethase activity correlate with the effects the different types of teas had on lipid metabolism of the rats.

Green, Black, Olong, Pu-Erh? Which tea to chose?

If we take a final look at the "whole picture", it appears that the exotic pu-erh tea would be the tea of choice, when you totally discard taste, price and whatever other factors may influence your choice. After all, it is was exactly as effective in ameliorating the weight gain as the black tea, induced an impressive +244% increase in AMPK phosphorylation and had what I, contrary to the medical establishment, would consider the "optimal" effect on the lipid profile of the rodents (a profound decreases in triglycerides, even below the level of rats fed the normal chow, and a +11% increase in HDL over the control diet despite high fructose feeding). The "classics", black and green tea, on the other hand, share a close and still notable second place, while the fancy oolong tea appears to be the least effective in this quartet of natural health promoters, the potency of which, and this is something I cannot emphasize enough, can hardly be explained based on their catechin content alone (cf. figure 1) and thusly renders the use of respective abstracts for the same purpose more than questionable.

Commercially Available Teas "Not Suitable For Human Consumption": Potentially Hazardous Amounts of Lead, Aluminum, Arsenic & Co in Every Cup

Would all commercially available teas have to be labeled like this?

I am usually not a fan of articles with titles like this one (see above) - they have what you call in Germany "Bildzeitungsniveau" (the German tabloid with news like "World about to disappear in a black hole, when CERN starts operating). It is however hard to resist the urge to use a headline like the one above, if the it fits the results of peer-reviewed scientific paper so well, as it is the case with the relatively recent paper from the University of Alberta and the Luleâ University of Technology in Sweden this SuppVersity article is (almost) all about.

The corresponding experiment, the results of which were published in the peer-reviewed open-access Journal of Toxicology in October 2013, already, addresses the increasing concern about contamination of foodstuffs and natural health products. With the emphasis being on foodstuff and health, it's only logical that tea, or more precisely all currently available off-the-shelf varieties of black, green, white, and oolong teas sold in tea bags were used for analysis in the said study.

So what did the researchers do?

Schwalfenberg, Genius (no joke, the 2n author is a real 'Genius by name') and Rodushkin conducted a three-step analysis in the course of which they analyzed the content of previously identified tea contaminants like aluminum, fluoride, mercury, lead, cadmium and arsenic (Fujimaki. 2004; Lung. 2008; Wang. 2008; Alvarez-Ayuso. 2011; Tan. 2012) in commercial tea preparations.

Table 1: There are not just bad, but also healthy minerals in tea!

Before we get to the "bad stuff", though, let's start with the positive findings of their investigation. The data in Table 1 is after all evidence enough that there are also "healthy" minerals in tea - the amount is not high enough to cover your RDA, but this does not mean that it could not be at least partly related to the undeniable health benefits researchers all around the world report for people who consume uncontaminated tea on a regular base. As a loyal SuppVersity readers you know most, if not all of them from previous articles on tea. The reason I still believe it's worth enumerating them again is that I don't want you to give up on your beloved (?) tea too easily - I mean, Coke is not an alternative and for coffee fungi and other stuff could make a similarly unhealthy "supplement" to your breakfast beverage:

• Cardiovascular benefits - When we are talking about health in general and heart health in particular, most people will think of green tea. That's pretty unfortunate, because there is ample research for all varieties of teas that they can lower blood lipids, provide "clean" and thus heart healthy energy, and exert antithrombotic and anti-hypertensive effects.
• Anticancer effects - Despite the fact that the anti-cancer effects have mostly observed in in-vitro studies, there is plenty of epidemiological evidence that tea drinkers have a lower cancer risk, than the average coke guzzler (not necessarily breast cancer, though ➫ SuppVersity Facebook News).
• Metabolic syndrome - While more recent studies clearly suggest that the active weight loss effects of tea, in general, and green tea, in particular, have been totally overblown, there is still a host of controlled trials, where adding tea (not necessarily green tea) improved the effects of a energy restricted diet. Compared to the rodent trials which are still fueling the myth of the potent thermogenic effects of (green) tea, the real world results in human beings are however downright disappointing.

• 

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  Anti-infective properties - Only few people (SuppVersity readers included - of course) know that green tea can be used as a mouthwash and is currently researched as an anti-bacterial food additive by researchers all around the world. According to a paper by Steinmann et al. (2013), the anti-infective effects are mediated by the antiviral, antibacterial, and antifungal properties of Epigallocatechin gallate (EGCG). The same EGCG about which you've read only recently on the SuppVersity that it is not exactly as useful as a fat loss adjuvant, as the hype would have you believe.
• Other beneficial effects - Under "Miscellaneous Effects", Schwalfenberg et al. also list the nephropotective effects of green tea, which could come very handy if you guzzle mercury contaminated green tea, everyday (unfortunately, mercury is your least problem with tea), the anti-depressive researchers have observed in people consuming 4+ cups of tea per day and the hitherto unconfirmed hypothesis that tea drinkers are (better) protected against Alzheimer’s and neurological decline.

In view of these benefits it's only logical that the Canadian + Swedish research team chose to repeat  the dichotomous health effects of drinking tea in the title of their paper "The Benefits and Risks of Consuming Brewed Tea" (my emphasis in Schwalfenberg. 2013)

Organic is not better than regular tea

To obtain a dataset that would be as comprehensive, accurate and practically relevant as possible the authors bought 30 different organic and non-organic white, green, oolong, and black teas from the the shelves of Canadian supermarkets and analyzed (a) the "raw" tea leaves (LEAF), (b) tea that had been steeped for 3-4 minutes (3MIN), (c) tea that had been steeped for 15–17 minutes (15MIN).

Know your teas: As a SuppVersity reader you will probably know that all teas come from the same plant. It's the processing that determines if we call it "white", "green", or whatever else:

• White tea: young leaves or new growth buds, withered, uncured, baked dry 
• Green tea: steamed or dry cooking in hot pans to prevent oxidation; dried tea leaves may be separate leaves or rolled into pellets (gunpowder tea)
• Oolong tea: withering of leaves under sun and warm winds with further oxidation standard between green and black teas
• Black tea: leaves are completely oxidized, withered

Due to the processing of the leaves tea from the same camellia sinensis plant can contain different amounts of contaminants depending on whether you buy it as white, green, oolong or black tea, or shredded green tea supplement.

Still, the main determinant is and remains the soil it was grown on (see Table 4)?

All tea samples underwent the same standardized procedures before they were analyzed in their raw form (cut / shredded leaves) or as an infusion that had been prepared with only one tea bag (containing 2-3g of tea) in 250 mL of distilled water in fine bone china cups.

As you will already have expected, the scientists did not just detect the previously mentioned "good minerals" (exact values see Table 1), and a host of other beneficial trace elements, i.e.

• boron 19–115µg/L, cobalt 0.4–3.56µg/L, 
• copper 26–106µg/L, chromium 0.2–14.6µg/L, 
• iron 19–62.5µg/L, manganese 534–6351µg/L, 
• molybdenum 0.03–0.131µg/L, 
• selenium <0.1–0.34µg/L, 
• vanadium <0.01–0.151µg/L, and zinc 44.6–187µg/L,

in their samples. Schwalfenberg et al. found highly significant and, more importantly, physiologically relevant amounts of toxic elements, as well:

Table 2: Established toxicant limits in supplements (µg/day).

If you look at the value in Table 3 and compare them to the limits in Table 2, there is one thing you should keep in mind: These limits have been set by average exposure, not based on toxicity tests - that sounds very comforting, right?

"Public health warnings or industry regulation indicated" -- It sounds pretty fearmongering and I would not have used it as a subheading right beneath the introduction, if the statement "Public health warnings or industry regulation might be indicated to protect consumer safety." (Schwalfenberg. 2013) was no literal citation from the conclusion of the paper I have here right in front of me.

Table 3: Levels of mercury (Hg), lead (Pb), aluminum (Al), arsenic (As) and cadmium (Cd) in tea infusions after 3-4 or 15-17 min of brewing; all values in µg/L (Schwalfenberg. 2013)

A brief glimpse at the data in Table 3 does moreover confirm there are plenty of toxins in the average Canadian super market tea, but it does not tell you how problematic the contamination actually is. To understand that you'd have to cimpare those values to the established toxicant limits Table 2, which do - and this is and will always be ridiculous -  obviously depend on where you live *sarcastic laughter*... but enough of the unproductive sarcasm, let's see what we've got:

"All teas contained significant amounts of aluminum. Tea  leaves contained from 568 to 3287 ng/g of tea. All brewed teas steeped for 3 or 15 minutes contained detectable levels of aluminum. The range was 1131µgm/L to 8324µgm/L steeping for 3 minute and 1413µgm/L to 11449µgm/L steeping for 15 minutes. Only 2 teas had levels above acceptable limits at 3 minutes of brewing but 6 of the teas had levels greater than the upper acceptable daily limit of 7000µgm/L. Clearly letting tea steep for longer than 3 minutes is not advisable. Two of the organic green teas had levels above 10,000µgm/L brewed for 15 minutes."

In view of the fact that tea is by far not the only aluminum source you are expose to, the high levels of this toxic metal that easily accumulates in the body should be reason enough not to brew your tea - especially not organic tea - for more than 3 minutes.

Organic tea is a worse offender than regular

If you take a look at the amount of lead in the various tea samples it becomes even more obvious that "organic" tea is not necessarily better for your organs, as well. This is particularly true for the best-sellers green and black tea, both of which contain significantly more lead in the "organic" vs. "regular" variety.

Table 4: Toxicant levels according to origin; Pb: lead, Cd: cadmium, Al: aluminum, As: arsenic (Schwalfenberg. 2013)

Probably the main factor that influences the toxicant levels of teas is the place of origin, thoug. As you can see in the overview in Table 4, the highest amount of arsenic, was detected in Chinese oolong teas (organic or regular). The total arsenic levels in all teas, which ranged from 0.06µgm to 1.12µgm/L for tea that had been steeped for 3 minutes to 0.08 to 1.27µgm/L for tea that had been steeped for 15 minutes was highest in white tea - obviously also from China. And last but not least, ...

"...[a]ll tea leaves had detectable levels of cadmium. 21 teas had detectable levels after 15 minutes brewing while only 18  teas had detectable levels after 3 minutes brewing suggesting that there is further leaching of this toxicant into the water over time. [As the overview in Table 4 already suggests] the highest level was 0.067µgm/L found in standard oolong tea from China." (Schwalfenberg. 2013)

Not listed in the tables are the levels of tin, barium, antimony and thallium, which were detected in all tea samples, but at levels of which the authors state that they don't have to be "considered to be of concern" (Schwalfenberg. 2013).

Should you stop drinking tea? You know that I don't like to tell people what to do. Unless, obviously I am 100% sure that I am convinced that there is a serious health risk involved.

In the case of green, black or white tea, the evidence that this is the case is yet insufficient. Personally, I will still make sure to check the geographic origin of the tea leaves (not where it was processed and packaged!) and avoid all products with the bad 5-letter word C-H-I-N-A on the label.

Bottom line: "Not of concern" is not exactly what I would say about the overall results of the study at hand. I mean, in the end, the high levels of toxicants in some of the commercially available tea preparations - specifically those from China - could actually explain why the real-world results with commercially available teas and tea supplements often fall short of the rodent studies, which are often conducted with highly purified green tea products from companies like Sigma Aldrich.

Ah, ... one last thing to keep in mind is that 18 out of 30 tested commercial tea preparations contained mercury in amounts that were as high as 20 ng/g, but did not make it from the leave to the tea. With your digestive tract being a much more efficient nutrient and (unfortunately) toxicant extractor than hot water, tea supplements could pose an even greater risk of heavy metal exposure than tea.

References:

• Álvarez-Ayuso, E., Giménez, A., & Ballesteros, J. C. (2011). Fluoride accumulation by plants grown in acid soils amended with flue gas desulphurisation gypsum. Journal of hazardous materials, 192(3), 1659-1666.
• Hayacibara, M. F., Queiroz, C. S., Tabchoury, C. P. M., & Cury, J. A. (2004). Fluoride and aluminum in teas and tea-based beverages. Revista de Saúde Pública, 38(1), 100-105.
• Lung, S. C. C., Cheng, H. W., & Fu, C. B. (2007). Potential exposure and risk of fluoride intakes from tea drinks produced in Taiwan. Journal of Exposure Science and Environmental Epidemiology, 18(2), 158-166.
• Steinmann, J., Buer, J., Pietschmann, T., & Steinmann, E. (2013). Anti‐infective properties of epigallocatechin‐3‐gallate (EGCG), a component of green tea. British journal of pharmacology, 168(5), 1059-1073.
• Tan, Z., & Xiao, G. (2012). Leaching characteristics of fly ash from Chinese medical waste incineration. Waste Management & Research, 30(3), 285-294.
• Schwalfenberg, G., Genuis, S. J., & Rodushkin, I. (2013). The Benefits and Risks of Consuming Brewed Tea: Beware of Toxic Element Contamination. Journal of toxicology, 2013.
• Wang, X. P., Ma, Y. J., & Xu, Y. C. (2008). [Studies on contents of arsenic, selenium, mercury and bismuth in tea samples collected from different regions by atomic fluorescence spectrometry]. Guang pu xue yu guang pu fen xi= Guang pu, 28(7), 1653-1657.

Coffee Rules, Green Tea Sucks!? Study Links Green Tea to Insulin Resistance and Coffee to Insulin Sensitivity. Statist. Outlier, Long- vs. Short Term Effect or Heavy Metal Toxicity?

I can't tell if bathing in coffee is healthier than in tea, but my gut tells me that it is.

Coffee may rob your sleep (see "Sleepness Nights: Are Pre-Workouts and A Huge Cup of Coffee Messing With Your Sleep?" | more), but if you look at the currently available epidemiological data, the average coffee drinker is still a pretty healthy chap. Whether this is due or in spite of the stimulating effects of caffeine is not quite certain, but a closer look at its molecular composition reveals that the average cup of real coffee has at least as many potent antioxidants, as green tea. From a molecular perspective coffee is thus by no means inferior to the catechin-laden purported health-elixir green tea. With its glucose-6-phosphatase inhibitory (van Dam. 2006) and insulin sensitizing effects (Shearer. 2003) of its chlorogenic acid and quinide, coffee has, just like green tea, tons of animal data to support its potent anti-diabetic effect.

What's healthier tea or coffee?

If you asked one hundred people, what they'd choose, coffee or green tea, if personal preferences weren't an issue and their only criteria were "beneficial health effects", I am 100% convinced that the vast majority would go with green tea. That's actually quite natural, the media does after all hype every epidemiological study that supports the notion that green tea drinkers are the healthiest chaps on earth. Studies like the one researchers from the National Center for Global Health and Medicine in Tokyo are about to publish in the venerable scientific journal Metabolism, on the other hand, are rarely present on any of the major science news outlets.

Did you know that... An inverse association between coffee consumption and HOMA-IR has been observed in the US, Sweden, the Netherlands and multi-ethnic Asian populations, the study at hand is yet the first to confirm the existence of health benefits in a Japanese population.

This is where the SuppVersity comes into play. Your place to learn that Pham et al. observed an "unexpected", statistically significant association between green tea consumption and elevated HOMA-IR levels - in other words: The regular consumption of green tea was associated with an impaired glucose metabolism / lower baseline insulin sensitivity.

Figure 1: Relative differences to coffee / green tea "no consumers" in subjects who drink different amounts of coffee and green tea every day; p-values are given in boxes only for significant changes (Pham. 2013).

These results were obtained using data from cross-sectional epidemiological surveys that had been conducted among employees of three workplaces, two municipal offices in Kyushu and one
manufacturing company, in Kanto in 2009 and 2012. Pregnant women and subjects reporting a history of stroke or cardiovascular disease (n = 25), cancer (n = 27), diabetes (n = 52) and chronic kidney disease (n = 9), as well as those who were current usersof anti-diabetic drugs (n = 1) or under medical care for hepatitis (n = 4) were excluded to minimize the influence of confounding factors and be able to make a statement about the associations between coffee and tea consumption and glucose management in the average healthy Japanese worker.

Table 1: Characteristics of the study subjects by coffee consumption; the yellow mark indicates stat. sign. inter-group differences (Pham. 2013)

"Information about dietary intake during the preceding month was obtained using a validated brief self-administered diet history questionnaire (BDHQ). Dietary intakes for 58 food and beverage items including coffee and green tea, energy, and selected nutrients were estimated using an ad hoc computer algorithm for the BDHQ, with reference to the standard tables of food composition in Japan.

The response options for coffee or green tea consumption were never, < 1cup/week (wk), 1 cup/wk, 2-3 cups/wk, 4-6 cups/wk, 1 cup/day (d), 2-3 cups/d, or ≥4 cups/d." (Pham. 2013)

It is probably not surprising that the comparatively detailed dietary analysis revealed significant correlations between the consumptions of coffee and green tea (Spearman’s r= 0.83 and 0.77 for coffee in men and women, respectively; Spearman’s r= 0.68 and 0.64 for green tea in men and women, respectively) - with a high enough subject base you can however subtract the individual influence of the two out.

Is there any reason green tea could compromise our insulin sensitivity

I have to admit that there is little direct experimental evidence that would explain the observations th researchers made, but if you remind yourselves of the first serving of the "Supplements to Improve and Restore Insulin Sensitivity" Series (overview), you will remember that the anti-diabetes effects of green tea / green tea supplements are - if they occur at all - indirect ones.

Don't forget that caps and pills are not worth a penny without you committing to the all the lifestyle changes I outlined in episode one of the "Supplements to Improve and Restore Insulin Sensitivity" series.

Unlike the bioactive substances in coffee, which have a direct beneficial effect on skeletal muscle glucose uptake, those of the often-hailed green tea catechins are primarily side effects of improvements in lipid metabolism and reduced chronic inflammation.

Assuming that the average study participant did not have significantly elevated blood lipids and wasn't chronically inflamed either, this would explain the absence of improvements in insulin sensitivity. What it doesn't explain, though, is the fact that the insulin sensitivity decreased - irrespective of the accumulating evidence which suggests that even diabetics don't benefit from green tea supplementation (latest example from Nov, 8  Wang. 2013)

Usually this is, when you take a look at the discussion in a scientific paper, read, digest and get an idea of what could be a reasonable explanation for unexpected phenomena like this. The conclusion of the paper at hand, does yet only summarize the existing scientific evidence that the vast majority of "previous studies have shown no association between habitual green tea consumption and fasting glucose" (Pham. 2013):

• a Japanese study among 1542 men reportedmarginally-significant higher odds ratios for IR with higher habitual consumption of green tea (T Otake April 2013, personal communication of the authors of the study at hand)
• Rebello et al. reported no association between green tea consumption and HOMA-IR among a multi-ethnic Asian population
• a meta-analysis including 6 clinical trials found no evidence to support an effect of green tea catechins on HOMA-IR

As Pham et al. points out conclusive evidence for or against the benefits of green tea consumption from long-term + large-scale trials is missing. Most clinical trials including those in in the previously cited  meta analyses had relatively short-term intervention (4-24 wks) and modest sample sizes (23-88 subjects). Without further research it is thus more or less impossible if genetic, lifestyle or other confounding variables or a hitherto overlooked negative long-term effect of green tea are responsible for the results. 

Table 2: Levels of toxic trace elements in tea infusion; data compiled by Tanmoy Karak, R.M. Bhagat (2010)

Aside from biological factors, the disappointing results could also be the consequence of the quality of the tea. In Japan, the upper tolerable levels for lead (Pb) are for example 4x higher, than in Europe (20mg/kg vs. 5mg/kg). With the ever-increasing Pb concentrations in tea leaves (Jin. 2005), lead and other toxic elements (see data in Table 2) could be turning the health elixir into an increasingly toxic cocktail.

"Coffee, Tea, Cacao, Caffeinated Sodas & Breast Cancer: 5+ Cups/Day?! Study & Meta-Analysis Show, It May Take More Coffee Than Previously Thought to Ward Off Breast Cancer" | more

Treat with caution: I strongly recommend not to overestimate the results of the study at hand - neither the negative ones about green tea, nor the positive ones about coffee. A BMI-stratified analysis did after all reveal that the inverse association (not causation) between coffee consumption and HOMA-IR was really significant only in the overweight/obese, but not in normal-weight, individuals.

In view of the absence of a reasonable explanation for the pro-diabetic effects of chronic green tea consumption (it may in fact be heavy metals; see Table 2), I would not suggest you switch from green tea to coffee, if you don't like it. If you are a coffee-boy or -girl, anyway, the study at hand confirms that reductions in diabetes risk are not a good reason to give up on your beloved brown brew ;-)

References:

• Jin CW, He YF, Zhang K, Zhou GD, Shi JL, Zheng SJ. Lead contamination in tea leaves and non-edaphic factors affecting it. Chemosphere. 2005 Nov;61(5):726-32.
• Wang X, Tian J, Jiang J, Li L, Ying X, Tian H, Nie M. Effects of green tea or green tea extract on insulin sensitivity and glycaemic control in populations at risk of type 2 diabetes mellitus: a systematic review and meta-analysis of randomised controlled trials. J Hum Nutr Diet. 2013 Nov 8.
• Karak T, Bhagat RM. Trace elements in tea leaves, made tea and tea infusion: A review. Food Research International. 2010; 43(9):2234–2252.

Theanine or Caffeine? Soda, Black or Green Tea? What's Going to Get Your Brain Going? Plus: What About Sleep?

Caffeinated soft drink, coffee or tea, caffeine alone or caffeine + l-theanine what's going to yield the desired afterburner effect for your brain? The answer to this question came out probably less straight forward than you'd expected.

"L-theanine, coffee or both? What's going to get your brain going?" That's the question form the title of today's SuppVersity article and it's a question with an astonishingly simple answer:  Both!

I guess you will be well aware that both caffeine and l-theanine have scientific evidence to support their usefulness as cognitive enhancers (Quinlan. 2000; Hindmarch. 2000; Nathan. 2006). Their interactions however have not been studied that extensively.

It's thus worth to take a closer look at the data Hira Zameer et al. collected for their most recent paper in the International Journal of Endorsing Health Science Research - data on the effects these agents can have on the cognitive performance and reaction times of 87 healthy young women (18-19 years), when they are consumed as part of hot and cold beverages (Zameer. 2013)

Compare to caffeine, which is literally on everyone's lips, only few people actually know what l-theanine is. Quite often you will see it being mislabled as the "the caffeine in tea" and that despite the fact that it is not even a methylxanthine, but (as the "L-" already suggests) an amino acid. Against that background it appears prudent to start today's SuppVersity article with a mini-summary of the the (astonishingly few) things we know about gamma-glutamylethylamide or 5-N-ethyl-glutamine, an amino acid and a glutamic acid analog that's - who would have guessed that - primarily found in tea.

L-theanine - the "tea caffeine"!?

L-theanine has gained quite some attention in the field of neuroscience. Kakuda et al., for example report significant neuroprotective effects in their 2002 paper. Protection is however not the only thing l-theanine can do for you. Previous studies have shown that it has direct beneficial effects on the activity of alpha frequency band (8–14 Hz), the cellular pacemaker of the human body (Kobayashi, 1998; Juneja, 1999).

Not to be confused: L-Theanine vs. theacrine as in "Theacrine Will Get You Going - Every Day! Camellia Kucha Alkaloid Acts via Dopamine and Adenosine" | more

In this context it's important to know that l-theanine has, in contrast to many other agents, the ability to cross the blood-brain barrier. It does so relatively easily, but not rapidly: Based on the current scientific evidence it takes ca. 30 minutes from the moment of its ingestion, before the first changes in neurotransmitter levels can be observed.

Structurally, L-theanine is similar to the excitatory neurotransmitter glutamic acid (Nathan. 2006). Consequently, L-theanine has the ability to antagonizes the central effects of glutamate by inhibiting glutamate reuptake and blockade of glutamate receptors in the hippocampus (Kakuda. 2002). This process goes hand in hand with an increased release of the "calming" neurotransmitter GABA and a concomitant decline norepinephrine levels.

In view of its GABA-ergic effects, it's not really surprising that L-theanine has also been found to ameliorate the blood pressure rising effects of caffeine and tone down the CNS responses (Eschenhauer. 2006) - quite a neat effect for an agent you get for free with your daily dose of caffeine in tea, isn't it?

Don't be fooled - tea will also mess with your sleep quality, but as data from an Y2K study by Hindmarch et al. shows, "day-long tea consumption produces similar alerting effects to coffee, despite lower caffeine levels, but is less likely to disrupt sleep." During the study (results see figure on the left), the drinks were administered on four occasions during the day (0900, 1300, 1700 and 2300 hours).

In subjects who had to perform a standardized series of stressful tasks, L-theanine has been shown to reduce the heart rate and salivary immunoglobulin A release via direct inhibition of the excitation of cortical neurons (Kimura. 2007). With the close connection between stress exposure, the activation of the sympathetic nervous system and the ensuing release of vasoconstricting hormones, it is not unlikely to assume that L-theanine's blood pressure lowering effects are a simple result of its ability to buffer the CNS activity and reduce the adrenergic tone (Kulkarni. 1998; Matthews. 2004).

Enough of the past, let's get to the most recent results

Now that you are in the know about some of the most prominent effects of l-theanine consumption, let's see how it fares in a direct comparison to everyone darling - caffeine!

Figure 1: Effects of soda, (black) tea and green tea ingestion on reaction time, concentration test performance, blood pressure and heart & pulse rate (Zemeer. 2013)

I already mentioned that the subjects, 87 young adult females (18-19 years of age) were randomly assigned to three groups

• Group A consumed a cold beverages in the form of soft drinks (caffeine only)
• Group B consumed a serving of black tea (caffeine + l-theanine)
• Group C consumed a serving of green tea (min. caffeine + l-theanine)

Before and 45 min after the beverage ingestion the scientists monitored the cardiovascular and neurophysiological responses. After the "immediately post" data had been collected, all participants engaged in a series of standardized reaction time and concentration tests that yielded astonishingly similar results:

• Both tea preparations "proved to be more sufficient in enhancing concentration and focusing power of the individuals by reducing the distractions during a task at hand" (Zemeer. 2013)
• The concentration levels during a passage reading task in the tea condition were likewise significantly higher (p < 0.05) than in the soft drink condition, which had only marginal effects on the subjects' ability to focus.

The analysis of the cardiovascular parameters, on the other hand, showed that all groups experienced a decline in systolic blood pressure, surprisingly,

Ever wondered about the "exact" pharmacology of caffeine? Tom Edwards captured it in 1990.

"[...] a significant reduction in systolic blood pressure by 13 and 19 mm Hg was evident amongst the candidates of group A and C who were assigned for the intake of soft drink (caffeine) and green tea (L-theanine), respectively (p < 0.05) as compared to individuals who were belonged to tea (caffeine + L theanine) consumption group. Similarly, a considerable decline in diastolic blood pressure by 12 mm Hg was more noticeable among the participants who were subjected to consume soft drink (caffeine) and green tea (L-theanine) (p < 0.05) as compared to the group B, tea consumers.

Physiological rise in the heart rate of the individuals was observed when their basal heart rates were taken before and after consumption of hot and cold beverages. But a less significant rise in heart rate by 1bpm was remarkable among group C (L-theanine) candidates (P=0.31). In contrast to heart rate, a significant increase in pulse rate by 10 bpm was reported within the members of group C, green tea (L-theanine) consumers (P=0.01). " (Zemeer. 2013)

If you look back at my brief summary of the current data on l-theanine in the upper part of this article, you will probably find the increase in blood pressure and the modulatory effects on the heart rate of the subjects odd - in the end, it is however perfect evidence that the effects of neurotransmitters and agents that can influence their levels and ratios are hard, if not impossible to predict. As with GABA (see "SuppVersity Science Round-Up: Paradoxical Effects of GABA. Plus: GABA-Alternatives" | read more) it may thus well be that tea really psyches you up and a "simple" coffee, where caffeine runs the whole show, is much better suited for you than a huge cup of black or green tea.

SuppVersity Suggested Read: "Green Tea Extracts for Building Strength & Size and Losing Weight - Fact or Fraud? Or, Why It is Always Worth Taking a Look at the Data that Is NOT in the Abstract. " | read more

So what do we make of these results, if the effects are so "difficult to predict"? Unlike the prediction the answer to this question is actually surprisingly straight forward, because all uncertainties aside, the study at hand did eventually confirm what most people know from their own experience: Tea, unlike coffee has a stimulatory, yet calming effect and is thus slightly more useful, whenever you are looking for focus and mental clarity.

If you want to tear down the gym, the rather aggressive and agitating effects of "unbuffered" (=no l-theanine around) of caffeine should be your first choice - unless, of course, the agitation turns into anxiety and instead of hammering away curl after curl you find yourself sitting on the bench shivering of negative excitement.

References:

• Eschenauer G, Sweet BV. Pharmacology and therapeutic uses of theanine. Am J Health Syst Pharm. 2006 Jan 1;63(1):26, 28-30.
• Hindmarch I, Rigney U, Stanley N, Quinlan P, Rycroft J, Lane J. A naturalistic investigation of the effects of day-long consumption of tea, coffee and water on alertness, sleep onset and sleep quality. Psychopharmacology (Berl). 2000 Apr;149(3):203-16.
• Nathan PJ, Lu K, Gray M, Oliver C. The neuropharmacology of L-theanine(N-ethyl-L-glutamine): a possible neuroprotective and cognitive enhancing agent. J Herb Pharmacother. 2006;6(2):21-30. 
• Kakuda T, Nozawa A, Sugimoto A, Niino H. Inhibition by theanine of binding of [3H]AMPA, [3H]kainate, and [3H]MDL 105,519 to glutamate receptors. Biosci Biotechnol Biochem. 2002 Dec;66(12):2683-6. 
• Kimura K, Ozeki M, Juneja LR, Ohira H. L-Theanine reduces psychological and physiological stress responses. Biol Psychol. 2007 Jan;74(1):39-45.
• Kulkarni S, O'Farrell I, Erasi M, Kochar MS. Stress and hypertension. WMJ. 1998 Dec;97(11):34-8. Review.
• Kuriyama S, Shimazu T, Ohmori K, Kikuchi N, Nakaya N, Nishino Y, Tsubono Y, Tsuji I. Green tea consumption and mortality due to cardiovascular disease, cancer, and all causes in Japan: the Ohsaki study. JAMA. 2006 Sep 13;296(10):1255-65.
• Quinlan PT, Lane J, Moore KL, Aspen J, Rycroft JA, O'Brien DC. The acute physiological and mood effects of tea and coffee: the role of caffeine level. Pharmacol Biochem Behav. 2000 May;66(1):19-28.
• Zameer et a.. Comparative Effects Of Caffeine & L-Theanine Consumption On Subjective Cardiovascular Signs And Neurophysiological Responses. International journal of endorsing health science research. 2013; 1(1): 38-42.

Milk, Tea & Honey - Two Things Don't Belong: Milk & Sugar Potently Reduce Antioxidant Effects of Green & Black Tea

Chi Latte is a sugar bomb, but no healthy, antioxidant beverage.

Over the past couple of weeks it has become relatively quiet in the "tea is good for your health", "tea makes you lose weight magically", "tea reduces diabetes risk", etc. column of the science news here at the SuppVersity, and in general. Ok, you still got your daily "green tea reduces inflammation study", but let's face it. That's boring.

What is interesting, however, are the results of a recent study that's about to be published in Food Chemistry (Korir. 2013). In this very paper, a group of researchers from the Egerton University in Kenya, the Association for Strengthening Agricultural Research in East and Central Africa in Uganda and the Tea Research Foundation of Kenya report that...

Adding milk or sweeteners to your tea will reduce its antioxidative capacity

And the effects the researchers observed in vitro and in vivo, were pretty significant, as you can see in the data I plotted for you in figure 1 & 2:

Figure 1: Antioxidant activity of green and black with different milk concentrations. No sweetener added (Korir. 2013)

Now, the first question I had, when I glimpsed at the results was "wtf. of course will the antioxidant effects of tea decrease in response to a decrease in the amount of tea per volume of liquid decreases"; I mean, that's exactly what happens when you add 10% of milk to your cup of tea at home. It becomes "dilluted" (usually you would not use that term if you put milk into something, but that's what it is). Now, the obvious question is: Was that even the case? Let's take a look at what the methods section of the paper can tell us:

Based on the results of the study at hand, we cannot really say whether adding milk to your tea after brewing it will reduce its antioxidant capacity. Luckily we do have data from a previously conducted 2011 study by Ryan et al. I wrote about in July 2011 that confirms: Adding milk after brewing reduces the FRAP (measure of antioxidant activity) value of tea more than the same amount of water does | read more

"Each infusion was prepared by infusing five grammes of coarse tea samples in 100ml of boiling distilled water in a 100ml volumetric flask and stirring with a magnetic stirrer on a hot plate for 10 minutes. Tea infusions with milk were made using 5g of tea and different concentrations of milk (2%, 4%, 6%, 8%, 10%, 20% and 40% (v/v milk/water). Infusions with milk and sugar were brewed with 3g and 10g of sugar plus the several concentrations of milk, and those with milk and stevia (0.1g and 0.3g) wereprepared. Similarly, teas with several concentrationsof milk plus 3g and 10g honey were prepared. All the above tea infusions were strained through cotton wool to remove the tea particles and left to cool to room temperature [before the antioxidant activity of the] prepared tea extracts was determined using the 2, 2’-diphenyl-1-picryhydrazyl radical (DPPH) method." (my emphasis in Korir. 2013)

I guess, you will already have gotten it, right? By adding the milk before the brewing, the scientists did manage to get around the dilution effect, but at the same time they reduced the practical relevance of their results to zero. Why? Well, do you brew your tea with the milk already in it? I don't think so... so if it were not not for the 2011 study by Ryan et al. I would say: The verdict on milk is still out there. With the pertinent results from the Ryan study, however, you can be assured that adding milk to your tea makes it a less potent ROS scavenger.

Figure 2: Mean values of antioxidant activity of sweetened plain black tea (Korir. 2013)

Obviously, the same limitations also apply to the real-world significance of the effects of pre- vs. post-addition of sugar, honey and stevia (see figure 2), of which the scientists suspect that they may be a result of

"[c]omplex compounds, such as pentagalloylglucose (PGG), tetragalloylglucose (4GG) and trigalloylglucose (3GG) [that] are likely to be formed as glucose interacts with the gallic acid in tea where by the glucose hydroxyl groups are serially substituted by gallic acid." (Korir. 2013)

These glucose complexes would then bind with the bovine serum albumin and other proline-rich proteins present in milk and thus alter the biological activity of tea molecules (Chitpan. 2007).

So why is honey the worst then?

Honey has been shown to possess significant antioxidant activity of its own. The latter is ascribed to the presence of compounds such as chrysin, pinobanksin, vitamin C, catalase, and pinocembrin that are thought to function as antioxidants (Valentini. 2010). We would therefore actually expect to see an increase in antioxidant activity, when we put honey into our teas, right? So what's the reason that the exact opposite happens and that honey was found to be the most inhibiting sweetener in both plain and black teas with milk? The answer is: We don't know.
 
What we do know, however, is the fact that we are actually not interested in the mere presence of maximal amounts of antioxidants in tea, but rather in their biological effects on the antioxidant defense system of our bodies; and the correspoding image that emerges based on the accompanying rodent study is more complex than the in vitro data would have suggested:

Lack of drive? Theacrine will get you going | read more

"The highest levels of GSH were recorded in plasma after 2 hours of tea consumption. The GSH levels due to various types of tea differed significantly (p<0.001) in the same tissue at different time intervals [...]. Highest GSH levels were recorded for black tea fortified with 2% milk in plasma, as compared with the other teas. However, in kidney and brain tissues, higher GSH levels were recorded for plain black teas after 2 hours and 4 hours of tea consumption, respectively. The GSH levels in the liver were similar to those in the brain but the peak in the liver was after 30 minutes." (Korir. 2013)

Now, while there is still no place for sugar in your tea, the reputation of milk is partly restored - but only if it's used in very tiny amounts. The Chi Latte you see in the head of this article still remains "the soda among the teas" and looking at the photograph I would assume that the effect of this particular incarnation of "sugar milk with a splash of tea in it", is probably more detrimental to your health than a whole bottle of Coke.

---

Catechin content of the leaves of green, oolong, black & pu-erh tea

Bottom line: Drinking tea is more than just a means of getting your antioxidants in. Against that background I am hesitant to suggest that everyone must drink his/her tea without milk and sugar, even if he/she hates the taste.

Nevertheless, cutting back on the amount of milk (<2%) and switching from honey or table sugar to stevia (and probably most other forms of artificial sweeteners) would be something to consider, if you want to make sure that the tea works its maximal antioxidant magic in your blood and organs.

References:

• Chitpan M, Wang X, Ho CT, Huang Q. Monitoring the binding processes of black tea thearubigin to the bovine serum albumin surface using quartz crystal microbalance with dissipation monitoring. J Agric Food Chem. 2007 Dec 12;55(25):10110-6.
• Korir MW, Wachira FN, Wanyoko RM, Ngure RK. The fortification of tea with sweeteners and milk and its effect on in vitroantioxidant potential of tea product and glutathione levels in an animal model. Food Chemistry. 2013 [accepted manuscript]

On Short Notice: Oxytocin to Boost Testosterone & Block Cortisol? Exercise for Life-Extension? Which Tea for Metal-Chelation? Which Fat to Reduce Calorie Intake by ~30%?

Image 1: This is still my preferred way to boost oxytocin - regardless of possible ergolytic effects ;-)

Due to the sudden heat-wave over here in good old Germany I thought, I'd use these early morning hours to get another installment of "On Short Notice" on it's way before my brain dries out (or I drown in the public swimming pool ;-). I hope you enjoy the four items on the recent interest in intranasal the hormone modulating effects of oxytocin, it's effect on cortisol and progesterone, estradiol and (I know you were waiting for that ;-) testosterone, my early morning / late evening (depending on whether you see this from my or Wyatt's perspective) 'intellectual' exchange on the potential longevity effects of exercise and why it probably is not life-extending in the literal sense, the different antioxidant potency of green, black and white tea and their ability to chelate metals (=help to remove all not just "bad" metals from the body) and the best fat, DHA or MUFA to blunt appetite and help you stick to your diet.

Don't forget to come back later today (or maybe early tomorrow for some of you ;-), for a third installment of "On Short Notice", which will hopefully suffice to "get rid" of the stock I have... ah, I did not forget about the Circadian Rhythm Series, by the way, it's just that the SuppVersity rhythm got slightly out of sync ;-)

• 

  Figure 1: Effects of 26IU of intranasal oxytocin at rest on progesterone, estradiol and testosterone in healthy men (large; based on Gossen. 2012); effects of 24IU or 48IU of intranasal oxytocin administered before a steady state cardio session on cortisol levels in healthy young men (small; from Cardoso. 2012)

  Intranasal oxytocin to block cortisol & boost testosterone A whole series of studies has been published recently; all of them have one thing in common, they investigate the various physiological and psychological effects of oxytocin. Of these, the two studies by Gossen et al. and Cardoso et al. are yet probably of greatest interest for the average physical culturist. After all, the researchers from the Centre for Research in Human Development at the Concordia University in Quebec (Canada) were able to show that the administration of 24IU (not the higher dose of 48IU, though;see figure 1) effectively reduced the increase in cortisol in a 70% HRmax steady-state cardio session in 17 healthy young men (aged 18–3; mean ± SD; 23.1 ± 3.5), in the experiment they describe in their Aug 2012 paper in Psychoneuroendocrinology (Cardoso. 2012).
  And even though the German scientists from the University of Aachen report minimal, but statistically significant increases in testosterone in 8 young men (mean age 26.4 ± 2.6 years) at rest, 210min after the (likewise) intranasal administration of a minimally higher dose (26IU) of oxytocin (Gossen. 2012). Both of these observations are not just very similar to what your average natty test booster is supposed to do, their real-world effects are probably also as insignificant. Also, did you ever try to tear down the gym and rep out a couple of PRs a couple of minutes after having sexual intercourse? If so, you should actually be aware why oxytocin probably ain't the ideal pre-workout supplement - in this regard it is also somewhat unfortunate that Cardoso et al. did not do a real performance test (suggested read: "Will Sex Before A Competition Hamper Your Performance"; note: this is not about sex minutes before the competition ;-).
  And when it comes to building muscle, previous research from Phillips lab at McMasters University appears to suggest that blocking cortisol is a hilarious idea, anyway. After tall, cortisol was the only endocrine hormone the elevation of which in the vicinity of resistance training sessions showed a positive correlation (r=0.29, P=0.03 cf. West. 2011) with increases in lean muscle mass in the large-scale by West et a.
• Exercise gets rid of the junk in your body, but will it help increase your lifespan? Basically this could be the headline to an interesting exchange of thoughts, I just had with Wyatt Brown on the SuppVersity facebook wall - one I believe is well worth being "recorded" as a short news item. The discussion came about in response to me posting the link to a study by He et al. who found that the way exercise induces autophagy (=natural, healthy cell death) contributes to its beneficial effects in the prevention of all sort of ailments, above all cancer and neurological problems such as Alzeimer's & co, because it allows your body to get rid of the debris and junk that's accumulating from just living your life (no matter how healthy or unhealthy that may be). Since exercise is not the only thing that can ramp up autophagy, and caloric restriction (as in starving yourself to live longer) can do the same, Wyatt mused about whether or not you could achieve the same (more or less; for animals vs. humans) proven benefits of life-long caloric restriction by exercise.

  

  Image 2: Twin studies are one of the ways to identify whether genes or lifestyle are the fundamental determinants of how old we get. One of the consistent findings of the numerous pertinent studies is that lifestyle factors (diet, exercise, but also our outlook on life, friends and family!) determine how well we are able to use the time that our genes (or whoever you want) has granted us on earth. Not more, but not less, either: If 100 years are what we got, all exercise and healthy eating will allow us to make it to that age with great ease, not more... and let's be honest, if that was the biblical age of 100y, wouldn't it be ungrateful to ask for more?

  A very good question, indeed and one I do not have a definite answer to. In view of recent reviews of the role of exercise in the longevity of centenarians (the oldest of the old; cf. Venturelli. 2012), it does however seem more likely that exercise does not have direct effects on the life-span, but, as Huffman states, "[e]pidemiologic evidence in humans supports exercise as a strategy to reduce the risk of morbidity and mortality" (Hufmann. 2010). Unfortunately, a low mortality won't help you to make it past the 100 ± X years your genes have in stock for you. The insights into the genetic determinants from pertinent studies into single-nucleotide polymorphisms (SNPs ~ single gene variations) does support this notion (Sorensen. 2012): The oldest of the old don't stick out, because their genes protect them from premature death, but simply because their genes allow for more cell cycles to occur before the 'natural reserve'. We already know that telomere length is a fundamental determinant of this 'reserve', so that it is not really surprising that telomere length at birth is one of the most reliable predictors of longevity (Heidinger. 2012)!
  Now, if we just use a totally random number to use basic math to make us understand, what this means, we could say that your telemore length at birth may be sufficient to make it to age 100, assuming that it is not prematurely shortened or you are dying from whatever other "natural" (not accidents etc.) cause, such as cancer, metabolic syndrome, CVD etc., exercise will of course help you to make it to those 100 years, but when the say 100,000 total turn overs that your telomeres allow for are done, you are done as well - no matter how "healthy" you eat and how much you exercise in the 99.99 years before. If you complement this "preventive" (=mortality reducing) effect by literally living on the slow lane, i.e. downregulating all your metabolic processes by starving yourself, you will obviously slow down the turn-over rate, as well. For simplicity of the calculation we assume that all these processes are linear (which I can guarantee they are not) and you are eating so little that you achieve a 50% slow down. That would mean that your turn-over rate would be reduced from 1,000 / year to 500 / year. Your reserves would last 2x longer and, assuming you eat and exercise and thus decrease your mortality risk, will allow you to make it to the ueber-biblical age of 200years! Great? Well you decide...

• 

  Image 3: If you want to get rid of metals, white tea should be your tea of choice, if you are already low on iron, copper, zinc & co. you should at least drink it away from your meals, though.

  Different tea preparations different effects antioxidant activity and metal chelation ability  It is nothing new that green and black tea will have differential effects on your physiology. What is yet a novelty is a comparison of the antioxidant and metal chelating activity the exact same hand plucked leaves of a specific cultivar (in this case PC108, bred in Malawi, typically used for black CTC tea production) will have when it is used for the production of either white, two black (Orthodox and CTC; both methods produce leaves of fannings or dust grades that are commonly used in tea bags, CTC = crush + tear + curl is processed by machines, while orthodox usually involves a mixture of mashine and manual processing) or two green (w/ and w/out caffeine) teas - a comparison like the one Patricia Carloni and her colleagues present in their latest paper in Food Research International (Carloni. 2012).
  As you will probably have expected the least processed green tea exhibited the greatest, while the most processed CTC black tea the least antioxidant activity (green ≥ low-caffeine green > white ≥ black Orthodox > black CTC), what may come as a surprise though is the superiority of white tea in the metal chelation essay the scientists performed. Closely followed by the orthodox black tea, the CTC tea (<50% of the white tea metal chelating activity) and the two green teas (<25% of the white tea metal chelating activity).

• 

  Figure 2: Reduction in calorie intake on standardized breakfast 20min after the ingestion of 6ml of a lemon flavored oil emulsion and in the course of the day compared to no oil control (based on Harden. 2012)

  Fat satiety effects: DHA > Olive Oil (MUFA) > regular diet That would be the ranking according to the satiety effects of the different fatty acids, as elucidated in a recently published study in the British Journal of Nutrition (Harden. 2012). For their study, the researchers had recruited 18 healthy normal-weight men. In a single-blind, three-way crossover study design the subjects received a single 6ml dose of either DHA or oleic acid (olive oil is 60-80% oleic acid, alternatives would macadamia ~60% and high-oleic acid sunflower oil >82%) with lemon flavor. The day before, the subjects had consumed standardized diets. 20min after the ingestion of the emulsion, they had a standardized breakfast, went home and went about their regular daily business for the rest of the day.
  The telephone interviews the researchers conducted on the next day showed that the ingestion of the DHA emulsion had exerted an, as the researchers argue cholecystokinin (CCK) dependent, decrease in energy intake of -20% and -29% for the breakfast and the total daily energy intake, respectively. That would make DHA a pretty effective tool to stick to my often-suggested -20% caloric deficit when you're dieting - at least for healthy individuals. Whether this will work for the obese, let alone morbidly obese with their deranged satiety signaling remains to be seen, though.

As I mentioned in the introduction, already. This was not the last "On Short Notice" item for this weekend. So, digest this, have some sex to calm down (unless you are about to work out, obviously), and drink a cup of tea to increase your chance to make sure that your end is not arriving before it's time and you can come back for more ;-)

References

• Cardoso C, Ellenbogen MA, Orlando MA, Bacon SL, Joober R. Intranasal oxytocin attenuates the cortisol response to physical stress: A dose-response study. Psychoneuroendocrinology. 2012 Aug 10. 
• Carloni P, Tianob L, Padellab L, Bacchettic T, Customud C, Kayd A, Damian E. Antioxidant activity of white, green and black tea obtained from the same tea cultivar. Food Research International. 2012.
• Gossen A, Hahn A, Westphal L, Prinz S, Schultz RT, Gründer G, Spreckelmeyer KN. Oxytocin plasma concentrations after single intranasal oxytocin administration - A study in healthy men. Neuropeptides. 2012 Aug 9. 
• Harden CJ, Jones AN, Maya­Jimenez T, Barker ME, Hepburn NJ, Garaiova I, Plummer SF, Corfe BM. Effect of different long­chain fatty acids on cholecystokinin release in vitro and energy intake in free­living healthy males. British Journal of Nutrition. 2012; 108:755­-758
• He C, Sumpter R Jr, Levine B. Exercise induces autophagy in peripheral tissues and in the brain. Autophagy. 2012 Oct 1;8(10).
• Heidinger BJ, Blount JD, Boner W, Griffiths K, Metcalfe NB, Monaghan P. Telomere length in early life predicts lifespan. Proc Natl Acad Sci U S A. 2012 Jan 31;109(5):1743-8. Epub 2012 Jan 9.
• Huffman DM. Exercise as a calorie restriction mimetic: implications for improving healthy aging and longevity. Interdiscip Top Gerontol. 2010;37:157-74. Epub 2010 Aug 10. 
• Soerensen M. Genetic variation and human longevity. Dan Med J. 2012 May;59(5):B4454.
• Venturelli M, Schena F, Richardson RS. The role of exercise capacity in the health and longevity of centenarians. Maturitas. 2012 Aug 7.
• West DW, Phillips SM. Associations of exercise-induced hormone profiles and gains in strength and hypertrophy in a large cohort after weight training. Eur J Appl Physiol. 2012 Jul;112(7):2693-702. Epub 2011 Nov 22.