Chinese Black, Green & Olong Tea is NO Health Beverage. Lead, Chromium, Cadmium and Potentially Toxic Levels of Manganese + Endocrine Disrupting PFCs Are the Rule

"Pesticide pollution: Chinese tea may not be safe to drink," this is what you could read on the website of Greenpeace in 2012, already and obviously this has not changed over the last 2 years | read more

I've actually written about the problem with toxins in tea, specifically green tea from China, before and I wouldn't be too sure, whether bad news like the previously reported "-20% Reduction in Green Tea From Just 5 Cups a Day" (learn more) could not possibly be a result of heavy metals and/or other toxins, as well. This and the fact that the data I am going to talk about in the following paragraphs is based on analyses of 43 representative tea products (including 18 green, 12 Oolong, and 13 black teas) from 7 main tea production provinces in China makes today's SuppVersity article relevant for everyone who consumes green tea from China or of unkown origin - China is the cheapest, so guess, where it's from ;-)

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Apropos "Guess where it's from!", if I had to guess, I would say that 99% of the black, green and olong tea extracts in green tea, fat burner, pre-workout, anti-oxidant, and other commercially available supplements will be from China. The fact that cadmium (Cd), inorganic and thus toxic chromium (Cr) and lead (Pb) were present in samples from Zhejiang, Fujian, Yunnan, Anhui, Hunan, Guangdong and Taiwan is relevant for ~95% of the SuppVersity readers.

You think that's an old hat? Well, what about the perfluorinated compounds (PFCs) the researchers, who are by the way working for the China Ministry of Agriculture and thus certainly not interested in making Chinese tea look like a poisonous swill, detected in all samples. The concentration of these emerging and ubiquitous organic pollutants in the samples varied. In view of the already established negative health effects of which Eriksen et al. (2009), Corsinia et al. (2012) and Posta et al. 2012) write that they encompass...

• 

  Would all commercially available teas have to be labeled like this? A previous study which found also Aluminum & Arsenic in tea bags, would suggest just that | read more

  thyroid dysfunction, 
• preeclampsia,
• increased risk of high cholesterol
• increased risk of cancer, 
• liver dysfunction, 
• disruption of the immune system,
• disturbances of the endocrine (=hormone) system, 
• developmental delays, and
• fertility issues

...which could potentially occur with chronic exposure to comparatively low amounts of these toxins, this is certainly disconcerting.

PFCs are everywhere: Due to their toxic effects in humans and other organisms, PFCs were added to the list of banned chemicals in the Stockholm Convention on Persistent Organic Pollutants in 2009 (Ma and others 2012). Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) have been detected in animals and water samples from rain, river, wastewaters, and sea. They are present in plants and crops, including all twenty foodstuffs that were examined in 2004 in Great Britain by Gem et al. in 2006. PFCs are present in wheat, oats, potatoes, and maize (Stahl. 2009) and their concentration is the highest in plants / crops that grow in or close to the ground - including the peeled edible parts of carrots, potatoes, and cucumbers.

If you look at the maximal heavy metal content (individual circles in Figure 1) you will see that eventually, even the high manganese content of up to 240mg/100g could become problematic.

Figure 1: Box plots of Cd, Pb, Cr, Cu, Zn, and Mn contents in 43 tea products from south China. The central solid line within each box is the median, and the bottom and top of each box represent the 25th and 75th percentiles, respectively (Zhang. 2014); the values outside this range are plotted as individual outliers (o).

The upper tolerable intake level (UTI) of manganese is only 11mg for an adult. If you adhere to the recommended 3g per 150ml water you would thus exceed the UTI by ~30% with with the amount of tea you'd put into only 2 cups! That's bad news, even if the hot water does not extract the total amount of manganese. It is after all not unlikely that toxic effects such as the Parkinson-esque shaking (tremors), which is supposedly a direct result of the neurotoxicity of manganese (Dobson. 2004),  can occur with the chronic ingestion of subtoxic doses in the 5mg/day range, as well.

And while the combination of cadmium, lead and chromium is etching away your brain and nervous system, the PFCs, which were detected in form of PFOS in only 6 samples and in form of PFOAs in 33 samples, will launch an attack on your endocrine system. Unfortunately, there is no reliable information on whether or not chronic exposure to teas with  250ng/kg dw of this endocrine disruptor will or will not have permanent negative effects on your health.

Table 1: Contents of PFOA and PFOS according to origin (left) and type (Zhang. 2014)

What we do know, though is that Oolong teas were 15x more frequently contaminated than green tea. Apropos, if you look at the data in Table 1 you will see that the tea producers in the Anhui Province are either most generously intoxicating their produce with PFC-containing products, or plant their tea plants right next to some industrial complex. Here, more than 50% of all tested samples contained both PFOA and PFOS.

Green still the "greenest": In Germany "green" mean ecological and "clean" and at least for the 43 batchs of green, oolong and black tea this association holds for Chinese teas, as well. The results of the study at hand clearly show that black teas had - on average - higher amounts of heavy metals and PFCs in them than oolong or green teas. This doesn't change the fact, though, that the major and potentially toxic manganese offender in the study was a batch of green tea (unfortunately, Zhang et al. don't disclose the province it was from). So, don't make a mistake: Green tea is not generally a safe choice - at least if it's from China.

Bottom Line: Chinese tea is certainly not your best choice! I would not go so far as to say that you must avoid it like a plague, though. Firstly, we don't really know if the heavy metal and PFC levels in the produce from other countries are much lower. Secondly, only few of the samples may be considered "officially" hazardous to your health. And thirdly, there is insufficient data on both, the amount of heavy metals (specifically manganese) and PFCs that will leach out of the leaves, into your tea and make it from there across the gut lining into your blood stream, as well as their potential long-term consequences.

The initially mentioned "Drinking Green Tea Reduces Your Testosterone Levels" study, is yet only one out of countless "surprisingly" disappointing studies with green tea and green tea supplements the negate results of which could potentially be ascribed to the presence of heavy metals or PFCs in the green tea / green tea extracts that were consumed in the study. So, maybe, but just maybe, you want to take a brief look at the back of the next bag of green, oolong and black tea you buy to check, whether it's from China?

References:

• Dobson, Allison W., Keith M. Erikson, and Michael Aschner. "Manganese neurotoxicity." Annals of the New York Academy of Sciences 1012.1 (2004): 115-128.
• Ma, Jin, et al. "State of polybrominated diphenyl ethers in China: An overview." Chemosphere 88.7 (2012): 769-778.
• Stahl, T., et al. "Carryover of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) from soil to plants." Archives of environmental contamination and toxicology 57.2 (2009): 289-298.
• Zheng, H. et al. "Analysis of Trace Metals and Perfluorinated Compounds in 43 Representative Tea Products from South China." Journal of Food Science (2014). Accepted Manuscript. doi: 10.1111/1750-3841.12470

Natural Hormone Optimization Made Simple & Cheap: Avoid These 10 Anti-Androgens to Boost Testosterone & DHT

Image 1: I am not aware of the effect the process of making yourself up has on androgen levels, but the PCPs in many cosmetics could in fact lead to hormonal imbalances.

One of the things you hear and read increasingly often, when it comes to topics such as detoxification, the use of anti-inflammatory supplements or simply increased intakes of omega-3 fatty acids to counter the "hazardous omega-6 overload in your diet", is the analogy of somebody banging his head against a wall asking for a helmet, instead of simply stopping this stupid practice. Likewise, it does not really make sense to invest $50 into an already more or less worthless natural testosterone booster, when, at the same time, you are eating or even supplementing one of the items on the following list of proven anti-androgens:

• anti-androgenic drugs - cyproterone acetate, spirolonactone, flutamide, ketoconazole, finasteride & co.: It stands to reason that your doctor will have had good reason to prescribe you one or the other of the aforementioned drugs; and at least as far as the DHT blocker dustasteride is concerned, diligent SuppVersity students will be aware that it does not compromise testosterone-replacement-therapy induced changes in body composition. In this regard, it should however be mentioned that the pertinent study, I discussed on March 12, 2012 (cf. "Dustasteride Does Not Hamper Changes in Body Composition on Supraphysiological Doses of Testosterone") was not a training study and that, given DHT's hitherto not fully elucidated role in satellite cell recruitment and proliferation, it is well possible that we would have seen differences in weight training athletes.To use these drugs as a means to bolster up your testosterone levels is therefore not just risky and irresponsible, but plain out stupid.
• ATD (1,4,6-androstatriene-3,17-dione): Yes, surprisingly the potent anti-estrogen (aromatase inhibitor) and much-touted testosterone-booster ATD is a relatively potent anti-androgen. You can read all about ATD's anti-androgenic effects in an older blogpost here at the SuppVersity: "Anti-androgenic effect of ATD"
   
• Chaste tree (Vitex agnus-castus): Also sold to help your testosterone levels along, yet even more to counter the scientifically hitherto non-established phenomenon of "progesterone gyno", Vitex is another relatively commonly used supplement of which a 2007 study by Nasri et al. shows that it will probably reduce, not increase your luteinizing hormone (LH) and testosterone levels in parts, but not exclusively via dopaminergic pathways (Nasri. 2007)
• Green Tea (Camellia sinensis): As a diligent student of the SuppVersity you will already be aware of the differential effects of green tea and its catechins on serum testosterone levels; if you are interested, in the details you can read them up in "5 Cups of Green Tea Can Reduce Testosterone by Up to -20%"
• Licorice (Glycyrrhiza glabra): The phytoestrogens in licorice have been shown to reduce testosterone levels in women; glycyrrhizin and glycrrhetic acid exhibit anti-androgen effects in healthy (Armanini. 2003) and diabetic men (Fukui. 2003)  - there is yet also counter-evidence coming from Josephs et al., who were "unable to reproduce" previous results showing a licorice reduced reduction in the conversion of androstenedione to testosterone (Josephs. 2001), since the latter does yet reference a previous study by Armanini et al. the results of which the latter were able to repdroduce in 2003 (Armanini. 2003), it is save to assume that licorice does in fact reduce testosterone levels in diabetic and healthy men and women; and that despite the fact, that a more recent study shows that its corticosteroid (cortisol) modulating effects are probably of greater relevance than its impact on the androgens and other sex steroids (Sigurjonsdottir. 2006)
• Red clover: Extracts from red clover exhibit potent binding affinity to the androgen and progesterone receptor and "theoretical estrogenic activity expressed as equivalent E2 concentration is in the same range as recommended for synthetic estrogen" (Beck. 2003)
• Reishi (LinghZi): Red reishi is supposed to be the mushroom with the greatest anti-androgenic activity. A methanol extract from Ganoderma lucidum has been found to decrease testosterone-to-DHT conversion by up to 80% in a 2005 study by Fujita et al. (Fujita. 2005)
• Spearmint (M. spicata): At least in women spearmint tea has been shown to increase estrogen and luteinizing hormone in the follicular phase of their menstrual cycle (Aktodgan. 2007). In a 2004 study that was conducted on male rodents, on the other hand, the daily administration of peppermint tea (M. spicata) for a period of 30days lead to significant increases in luteinizing and follicle stimulating hormone and increases in serum testosterone, yet with the serious downside of "extensive degenerative changes in the germinal epithelium and spermatogenesis arrest compared with the findings in the testicular biopsies of the control group" (Aktogan. 2003)
• Soy and soy phytoestrogens: It goes without saying that you won't take your girlfriends pill, right? So why do you even remotely consider eating soy, let alone supplementing soy phytoestrogens? "I've seen soy consumption cause impotency in numerous patients." - Dr. John Crisler (male hormone expert) on my facebook wall in response to Jefferson. 2012; avoid feeding soy to your male offspring at all costs (Sherill. 2010; Leraiki. 2011; Siepmann. 2011)
• White Peony (Paeonia lactiflora): Also known as Chinese Peony, the ornamental plant has been shown to contain at least two compounds, 6'-O-galloylalbiflorin and pentagalloylglucos, which bind to the androgen receptor and thusly inhibit its activation by testosterone, DHT and weaker androgens (Washida. 2009).
• Xenoestrogens & Co - BPA (Bisphenol A as in plastics), PCPs (as in cosmetics), etc.: Can inhibit testosterone production by reducing the conversion of cholesterol to androgens (Feng. 2012) and estrogen-like effects (Nakamura. 2010); similar effects have been reported for all sorts of so-called "xenoestrogens", these are synthetic compounds that act as (mostly weak) estrogens in the human body and can induce permanent damage to the endocrine system and resproductive system, specifically in young boys and adolescents. In grown up men and women they have been linked to the development of various forms of cancer (Donovan. 2007).

I know, "avoid this... avoid that..." does not sound half as sexy as "with just three caps of our product you can boost your testosterone levels by up to 123.741%!... but you know what? Other than those red gren, blue, yellow, red and white caps in their mostly black, as of late yet often white (probably to suggest "drug-like" effects) boxes, it's totally free and, more importantly, it works!

+87% Increase in Testosterone Within 21 Days from a 100% Natural Supplement? Study Shows: Soy Bean Extract Can Do Just That While Wreaking Havoc on Your Testes. Plus: Corn Oil Reduces Testosterone to Estrogen Ratio by -50%!

Image 1: I guess the feed of those boars does not contain any corn oil and is spiked with both bisphenol A and soy bean extract - I mean, how else could you possibly explain those balls? (img dirtybutton.com)

Let me start today's post with a few questions: Would you buy a 100% natural product that can lower your estrogen levels by up to -98%, increase the weight of your testes by ~30% and, above all, boost your testosterone levels by a whopping +87%? I guess, at least all those of you who either have not read or not understood the Intermittent Thoughts episode on estrogen's role in skeletal muscle hypertrophy are just sitting there, nodding their heads... I would yet also venture the guess that this nodding will end pretty abruptly, now that I am about to tell you that this all natural testosterone booster is derived from the powder of 2kg of Glycine max soy beans via methanol extraction, subsequently freeze dried and capped into 600mg caps of which the average adult (~80kg body weight) is supposed to ingest two per day.

Chose your poison: BPA, soy, or maybe just some governmentally subsidized corn oil?

The preceding paragraph was an ironic, yet as far as the underlying facts and figures are concerned 100% accurate introduction to today's post which revolves around a study Evanski from the Mind&Muscle forum has brought to my attention (Norazit. 2012). The authors, a group of scientists from the University of Malaya in Kuala Lumpur, Malaysia, had set out to investigate the purportedly negative effects of what they call "soya bean extract" (interestingly this spelling of "soy", which is identical to the German version is probably the reason the study did not appear on my "interesting stuff for the SuppVersity radar", before ;-), bisphenol A, 17β-estradiol and "harmless" corn oil on the testis and endocrine system of juvenile rats.

Figure 1: Phytoestrogen content (µg/g dry weight; mind the logarithmic scale!) of soy bean extract an standard rat chow measured by LCMS (data adapted from Norazit. 2012)

To this ends, the scientists divided thirty 21-day old juvenile male Sprague-dawley rats (=the standard lab rat) into five groups, receiving either a standard diet (which contained an insignificant amount of soy, cf. figure 1) + 100mg/kg Tween 80 (a standard food emulsifier with derived from polyethoxylated sorbitan and oleic acid; this group served as control for the soy and the bisphenol group) or standard diet +100mg/kg of corn oil (Mazola; this group served as a control for the estradiol group because the 17b-e did not dissolve in the Tween 80), soy extract, bisphenol A (Aldrich Chemical Co.) and 17b-estradiol (the most active form of estrogen, which binds to both the alpha- and beta-receptor) for three weeks.

Note: It is (at least in my view) a lucky coincidence that contrary to the soy extract and the bisphenol, the estradiol did not solve in the Tween 80, so that the scientists had to come up with Mazola corn oil as a "positive control". I mean, if you take a look at the effects this supposedly neutral "solvent" had on the endocrine milieu of the peripubertal rats, it is no wonder that with the average testosterone levels of the male inhabitants of the #1 corn producer of the world, the Unites States of America, is on a constant decline.

At the end of the study period the rats were sacrificed, the testis were excised and their testosterone and estrogen levels were assessed using standardized enzyme immunoessay (EIA) kits from Caymen Chemical.

Figure 2: Section of seminiferous tubules from control Tween 80 group, BPA group and soy bean extract group; (1) maturing spermatids, (2) lumen filled with cellular debris, (3) vacuaolation, (4) interruption of spermatogenesis (data adapted from Norazit. 2012)

Even a layman can see that both the bisphenol A, as well as the soy bean extract treatments induced profound changes in the cell-morphology of the testes (cf. figure 2). Vacualation (3), i.e. formation of vacuoles in cellular tissue, was present in both, only the bisphenol A group showed the characteristic lumen filled with cellular debris (2). Visible signs of spermatogenesis (1) were visible in neither of the groups, a clear interruption of the latter (4), was yet observed only in the soy and the estrogen group (latter not shown in figure 2). Moreover, the estrogen treated animals were the only ones where the testis showed clear signs of apoptosis (cell death).

The "harmless" corn oil shifts the testosterone to estrogen ratio from ~1/1 to 1/2pg/ng

Reckless, as I am I decided to discard Norazit et al.'s distinction into the BPA and soy groups with the Tween 80 group as a control and the estradiol group with their corn oil control and just plotted the total body and total and relative testis weight gain, estrogen and testosterone levels relative to the Tween 80 group. In other words, I treated the corn oil group as if it was just another treatment group. This is obviously somewhat fishy, but if no scientist appears to be willing to investigate the potential negative effects of corn oil on the endocrine system of adolescent rodents (let alone humans), this is the only way for us to get respective data ;-)

Figure 3: Body weight gain, total and relative right testis weight, estradiol and testosterone levels in peri-pubertal rats after 21 days on diets containing 100mg/kg bisphenol A, soy bean extract, corn oil or 17b-estradiol (in soy bean oil); data expressed relative to Tweenn 80 (polysorbate + oleic acid) control (data calculated based on Norazit. 2012)

And if you take a look at the data in figure 3 (the vertical axis of which is by the way discontinuous!) it becomes clear that you better feed your boys a food solvent such as Polysorbate 80 (=Tween 80) than the "healthy" corn oil the US government is trying to con you into. After all, the administration of 100mg/kg corn oil (human equivalent ~16mg/kg) during puberty decreased the testis weight of the rats by -23% it reduced the amount of estradiol by -35% and the amount of testosterone by -66% and thusly shifted the testosterone / estrogen ratio in the peri-pubertal rodents from 1.11pg/ng to 0.57pg/ng!

BPA and soy compete for the title of "most potent endocrine disruptor"

Following the bro-scientific "the more the better" type of reasoning, bisphenol A and soy bean extract are two potential candidates for the "testosterone booster of the year"-award. After all both, the organic solvent bisphenol A, as well as the "natural toxin" (sorry, I just had to write that ;-) soy, exert potent (8x) and ueber-potent (100x) effects on the testosterone to estrogen ratio, which is 8.2pg/ng for BPA and 100.1pg/ng for soy!

Note: Neither I, nor the scientists have any clue as to why the results of this study are diametrically opposed to those of previous studies in which extracts from soy products reduced, not increased, testosterone levels in male rodents and monkeys(!), across-the-board (eg. Sharpe. 2002; Cline. 2004) - and that although Sharpe et al. observed an increase in the testosterone producing Leydig cells in their soy-formula fed monkeys. Whether the rats in the study at hand were in a state where similar effects temporarily increase testosterone output until the Leydig cells literally "burn out", or whether other effects were responsible for the temporary increase in testosterone, would have to be elucidated in future studies, the results of which you will obviously read here at the SuppVersity, first ;-)

So, even if we assume that the data is correct and there were no cross-reactions between components in the soy bean extract and the testosterone anti-body test, I would strongly caution against the use of either of this compounds to boost your testosterone levels - I mean what's the use of a wickedly skewed testosterone to estrogen ratio (which in and out of itself will probably mess up your health and can potentially hinder your gains, cf. "Are You Serming Away Your Gains?"), when, at the same time, your testicles turn into dysfunctional balloons?

Chamois Creme Potential Reason for Elevated Estrogen in Cyclists +Triathletes Have 2x More Testosterone Than Average Men and 71% More Than Active Individuals

Image 1: Norman Stadler 2004 winner of the Ironman Hawaii probably had a hell of a testosterone boost, when this photo was taken (img. Kai Baumgartner. 2004)

Disturbances of the endocrine (=hormonal) milieu are among the hall-mark features of what sport scientists call the "female athlete triad". The unholy trinity of osteoporosis, disordered eating and, as a direct consequence of the aforementioned hormonal imbalances, menstrual disorders. Men, the purportedly "stronger sex", on the other hand are supposedly pretty resistant to exercise-, or, I should say, overtraining-induced hormonal imbalances - bullshit? Well, probably... after all, with insufficient fuel and recovery everyone, man or woman will eventually maneuver him- or herself into a situation where his endocrine system is no longer functioning optimally. A recent study from UCLA does yet show that mother nature must have been aware that a) exercise is part of what the "hunters" (=us men ;-) do and that b) men are in the lucky position not to have carry a child full term - so, as long as they are we are not sick, there is no reason for mother nature to shut our reproductive system down completely.

What's worse? Cycling, or swimming, cycling and running?

To test the hypothesis that "serious leisure time athletes", in this case cyclists (>8h of intense training per week) and triathletes (>5h of intense training per week), are at much greater risk of developing training-related hormonal disturbances than the average "recreational athlete" who performs less than 3.5h of moderate exercise per week, L.Z. Fitzgerald and his colleagues from the School of Nursing at UCLA assessed the body composition, physical activity and hormonal and inflammatory markers of 107 healthy men (age 18-60 years).

Figure 1: Demographic and physical variables of the cyclists (n=46), triathletes (n=16) and recreational athletes (n=45) of which I believe that they me independent (caffeine, age) and dependent (body fat, lean body mass) confounding factors data expressed relative to the statistical average; calculated based on Fitzgerald. 2012

In figure 1, I have compiled a few of the demographic and physiological parameters of the the three study groups of which I believe that they may be confounding factors that may - independent of the type of exercise these men were doing - contribute to differences in the endocrine parameters between the highly active cyclists and triathletes and the moderately active recreational trainees. Of these, the higher age, which is obviously associated with a decline in testosterone levels, and the significantly higher caffeine intake in the cyclists (with 317.3mg/day this is well within the regions where it boosts testosterone, though; cf. Beavan. 2011) are independent, while both the amount of body fat (more = more aromatization = more estrogen and less testosterone), as well as the total lean mass the athletes are carrying around are obviously influenced by the type and amount of exercise they perform.

Figure 2: Estradiol, testosterone, SHBG, luteinizing hormone (LH) and follicle stimulating hormone (FSH) expressed relative to data from a reference cohort I "borrowed" from Brambilla et al. (2009); calculation based on Fitzgerald. 2012

Apropos, as you can see in figure 2 we do once again have one of my favorite (roughly!) bell-shaped dose-response curves (orange line), with the highest exercise load (cyclists - more than 8h of training per week) producing the most unfavorable testosterone to estrogen ratio, a pronounced peak that is associated with the medium to high volume, high intensity approach of the triathletes (>5h) and a slightly above average testosterone to estrogen ratio in the group of recreationally active men.

If you cherish your manhood, man up and don't use chamois cream

A closer analysis of the individual hormone levels does yet reveal a pretty awkward phenomenon: In spite of having the lowest luteinizing hormone levels of all three groups (-56% below "my" reference, i.e. Brambilla. 2009) and an exorbitant amount of estrogen (+113% more than "my" reference) they also have the highest amount of testosterone in their blood. And while I am usually smart-assing scientists for following mainstream paradigms and not following up interesting / surprising results, this is one of the rare cases, where I really have to take my hat off to Mr. Fitzgerald and his colleagues, because I would never have thought of the somewhat shocking explanation the guys came up with:

Some cyclists apply chamois cream to their perineum area to help prevent chafing and bacterial infections related to bicycle saddle sores. The various commercial creams contain a variety of ingredients including lubricants, polymers, oils (jojoba, lanolin, mineral, olive, peppermint, rosewood, soybean, tea tree, St John’s wort), vitamins (A, C, D, E), and alcohols. Additionally, some of these creams contain parabens which are anti-microbial preservatives, but also weak estrogen agonists (Frederiksenet. 2011). In vitro studies demonstrate that parabens bind to estrogen receptors and initiate estrogenic cellular path-ways (Darbre. 2004).

And in fact, a follow up questionnaire confirmed the scientists' suspicion. While only 10% of the triathletes, who obviously cycle as well, used paraben-containing chamois cream roughly 50% of the cyclists applied them regularly to their best parts - with shocking side-effects:

Among the cyclists, there was a significant dose-dependent increase in estradiol levels with increasing years of chamois cream use for men using the cream for more than 4 years (p = 0.03) with notable effect size (partial n² =0.12).

If we briefly discard the high estrogen levels in the cyclists and take an objective look at what conventional wisdom tells us about the detrimental effects of high intensity endurance exercise in general and the arduous combination of swimming, cycling and running, also known as triathlon, this study does still provide enough evidence to cause another of our broscientific myths to totter...

...high intensity endurance exercise does not per se reduce testosterone levels!

Image 2: I wonder if there is a "don't use if you don't want to castrate yourself" warning anywhere on this tub of chamois crème.

At least in the study at hand, both triathlon training and cycling even at doses of >1h per day was associated with statistically significantly higher testosterone levels, statistically identical cortisol levels (cyclists: 309µg/dL; triathletes: 292µg/dL; recreational athletes: 376µg/dL) and - as if that was not beneficial enough - significantly reduced baseline interleukin 6 levels (-50% in cyclists; -74% in triathletes)... if future controlled studies are able to confirm these preliminary results, this would not only confirm the initial hypothesis that the male hormonal milieu is much more resilient than its female counterpart, it would also put a huge question mark beyond the underlying hypothalamic adaptation processes and the dose-response relationship - after all, these results to not contradict previous findings by Hackney et al., who did even coin a special term for the ultra-endurance exercise induced downregulation of the reproductive system: the "exercise hypogonadal male condition" (Hackney. 2008).