True or False: "Washing Your Fruit and Veggies is Useless - You Can't Wash Away the Pesticides, Anyway!"

It's a good idea to wash your veggies, but this is not the most effective method. Bath them in warm water, don't wash them under the faucet.

Despite the fact that I had my reasons to end the SuppVersity "True or False" Series back in the day. The popularity of the corresponding articles that appear from time to time as SuppVersity Classics on Facebook does yet tell me that you won't be mad at me, if I revive it and try to tackle a statement I've overheard in one of those infamous gym conversations between two ladies on the cross-trainer: "I always wash those pepper extra thoroughly, you know... tomatoes are among the veggies with the highest amounts of pesticides on them." Answer lady two: "Ha, you don't really believe the pesticides are on the outside of the tomatoes only, do you? They are in the tomato. Washing them will at best remove some of the dirt on their skin!"

True or False: "It's useless to wash your peppers."

False - I was surprised, when I realized that the answer to this True or False item was much easier to find than I had thought. It took me a while, though, before I found a study that analyzed data from more than just one vegetable variety, but the basic answer,  i.e. "No, it's not useless to wash your peppers - quite the contrary!" popped up right in my first cursory database search.

Figure 1: Amount of ethylenebisdithiocarbamates and chlorpyrifos on selected vegetable (µg/kg) before and after washing; the figure above the bars indicate %-change from pre to post washing (Chavarri. 2004; Randhawa. 2007)

If you look at the data of two studies I selected more or less randomly (see Figure 1) you will yet see that the effectiveness of the "wash away the pesticide approach" depends on both, the type of vegetable and the type of pesticide. With a mean total endusulfan reduction of >20% it should however be absolutely obvious that not washing your veggies would be wreckless.

Table 1: Current European Union Maximum Residue Levels in mg/kg (Council Directives 76/895/EEC and 90/642/EEC, last revised in June 2004)

Artificially contamination ➫ standardization: The baseline pesticide level of the vegetables in the Chavarri study was achieved by spraying fresh produce from controlled plots with no previous pesticide applications with those pesticides farmers usually use in the EU. The reason should be obvious: standardization. Thus, the pesticide levels were within the contemporary EU limits (s. Table 1) - something you cannot necessarily expect from every product you buy in the supermarket.

I mean, I shouldn't have to tell you to that it's unquestionably healthy not to be exposed to the full load of 24µ/kg chlorpyrifos and 1,626µg/kg ethylenebisdithiocarbamates (both have carcinogenic effects in humans; cf. Houeto. 1995, Josephson. 2005), from the tomatoes - specifically in view of the fact that 5.% of the tomatoes that are sold in the EU exceed the contemporary pesticide limits (Nasreddine. 2002) and would thus contain way more of these hazardous substances to begin with.

Aprospos washing! How do you do that?

You don't know how to wash veggies? Well, I obviously can't tell you what the absolute optimal way is, but what I can tell you is how scientists washed the specimen that were used in the studies the data in Figure 1 is based on: They placed the veggies in a dish or a clean lavatory with warm tap water and cleaned them with "gentle rotations of the hand" (Randhawa. 2007), before they grapped a conventional paper towel and blotted them dry.

Figure 2:  Illustration of the processing steps in Chavarri et al. (2007).

That's similar to what you do? Great, and you know what, I would bet that's not the only similarity between yourself and the average scientist. Just like you, scientists don't eat all their veggies raw. Consequently, both Chavarri et al. as well as Randhawa et al. conducted additional analyses of the pesticide content of their veggies after the produce had been blanched (the peppers were roasted, not blanched), peeled, pureed (Chavarri. 2004; see Figure 1) and cooked or peeled and cooked (Randhawa. 2007), respectively.

Figure 3: Relative ethylenebisdithiocarbamates and total endosulfan levels (in % of baseline) after washing, peeling, blanching / cooking & co. (Chavarri. 2004; Randhawa. 2007)

As you can see in Figure 3, each of these processing steps lead to a further reduction of pesticides. For the initially highly intoxicated asparagus, for example, even the last traces of pesticides ended up in the cooking water. If you would now decide to recycle the water for a soup or whatever, all your efforts to rid yourself of the pesticide would have been in vein.

"Conventional vs. Organic is not about getting more, but about getting  less for your money" | more

Bottom line: Wash your damn veggies you lazy *****! If you still don't believe that it's well worth spending this inconvenient extra-minute it takes to prepare warm water (28-32 °C), put your foods in, scrub a little with your hand and then continue processing them, I'd suggest you take a look at a recent meta-analysis from Ghent University in which the authors dealt with the exact same question and conclude:

"Reduction of residue levels was indicated by blanching, boiling, canning, frying, juicing, peeling and washing of fruits and vegetables with an average response ratio ranging from 0.10 to 0.82." (Keikotlhaile. 2010)

References:

• Chavarri, M. J., Herrera, A., & Arino, A. (2005). The decrease in pesticides in fruit and vegetables during commercial processing. International journal of food science & technology, 40(2), 205-211. 
• Houeto, P., Bindoula, G., & Hoffman, J. R. (1995). Ethylenebisdithiocarbamates and ethylenethiourea: possible human health hazards. Environmental health perspectives, 103(6), 568.
• Keikotlhaile, B. M., Spanoghe, P., & Steurbaut, W. (2010). Effects of food processing on pesticide residues in fruits and vegetables: a meta-analysis approach. Food and Chemical Toxicology, 48(1), 1-6.
• Nasreddine, L., & Parent-Massin, D. (2002). Food contamination by metals and pesticides in the European Union. Should we worry?. Toxicology letters, 127(1), 29-41.
• Randhawa, M. A., Anjum, F. M., Asi, M. R., Butt, M. S., Ahmed, A., & Randhawa, M. S. (2007). Removal of endosulfan residues from vegetables by household processing. Journal of Scientific and Industrial Research, 66(10), 849.

Chicken, Rice, Veggies & Oil and How Their Effects on Your Insulin & Glucose Levels Are 50% Off Those You'd Expect Based on the Calculated Glycemic Index of This Meal

The power of GI calculations is limited and even with meals as simple as the one in the picture, the calculated glycemic index can be ~50% off!

As a SuppVersity reader you've repeatedly read about macronutrient interactions, such as the insulin boosting effects of whey protein or dietary fat, studies that investigate the effects of the individual ingredients of a complete meal on the glycemic response healthy men and women, however, are scarce. Against that background the results of a recent study from the Clinical Nutrition Research Centre at the Singapore Institute for Clinical Sciences are of particular interest. After all, the Lijun Sun et al. (2014) determined the effect of co-ingesting a high-protein food (breast chicken), a fat (ground nut oil), a leafy vegetable or all three on the glycaemic and insulinaemic responses of white rice in healthy adults and did thus produce results that could be practically relevant for all of us - more relevant than inaccurately calculated GIs.

Use sugar alternatives if you want to improve your blood glucose!

Unsatiating Truth About Sweeteners?

Will Artificial Sweeteners Spike Insulin?

Sweeteners & the Gut Microbiome Each is Diff.

Sweeter Than Your Tongue Allows!

Stevia, Much More Than Sweet?

Artif. Sweetened Foods Good, Not Bad for Fat Loss.

Before we get to the study results, though, let's briefly recap what the researchers actually did: Sun et al. recruited twelve healthy participants (six female and six male) by means of advertisements, flyers and personal communications.

"Before inclusion into the study, potential participants were briefed on all aspects of the experiment and were given the opportunity to ask questions. Following the securing of consent, a health assessment was performed which included anthropometric measurements and a health questionnaire (giving details of food allergies/intolerance, metabolic diseases, special dietary needs and smoking habits). Those who fulfilled all the inclusion criteria [body mass index 18.5–24.99 kg/m2; blood pressure (BP)—systolic BP between 110 and 120 mmHg and diastolic BP between 75 and 85 mmHg; age 21–50 years; fasting blood glucose, 4–6 mmol/L; not on prescription medication, non-smoking; no genetic or metabolic diseases) were enrolled into the study." (Sun. 2014)

In addition, the amount of regular physical activity was quantified and subjects who were partaking in competitive sports and endurance events were excluded. Eventually, the scientists ended up with a group of normal-weight men and women at the age of 21–34 years.

Table 1: Composition of the test meals, ACHO = available carbohydrates.
Nutritional data were obtained from the manufacturers (Sun. 2014).

The subjects visited the laboratory 5 times (plus a baseline testing with a glucose solution). On each of these testing sessions, which were separated by at least one week, the subjects arrived at the laboratory between 7:30 and 8:30 after an overnight fast and received one of the five test meals from Table 1, which contained 194 g white of plain white rice,  254 g of white rice with fat, 294 g of plain white rice with chicken breast, 314g of white rice with vegetable and 474g of white rice with fat, chicken and vegetable, respectively.

Ground nut oil? I guess most of you will know the oil that was used in the study at hand as "peanut oil" and it is - as you will probably know, as well - not exactly high in "holy" omega-3 fatty acids. Rather than that, peanut oil contains oleic acid (46.8% as olein), linoleic acid (33.4% as linolein), and palmitic acid (10.0% as palmitin), as well as small amounts of stearic acid, arachidic acid, arachidonic acid, behenic acid, lignoceric acid, but not a singly milligram of omega-3s.
The test or reference food was then given to consume within 15 min. Further blood samples for glucose and insulin analysis were taken for the subsequent 180 min (every 15 min in the first hour and every 30 min for the subsequent hours) - a procedure that yielded the following results.

Figure 1: Glucose levels expressed relative to the ingestion of 250g of glucose (Sun. 2014)

The values in Figure 1 are expressed relative to the glucose response to 250g of pure glucose, of which a brief glimpse at the data tells you that they produce higher peak and incremental area under the curve (iAUC, a measure for the glycemia over the whole testing period) levels than any of the meals. Statistical significant differences were yet observed only for rice with chicken breast, rice with vegetable, and rice with fat, chicken and vegetable - yet not for the plain rice and the rice + fat meal (the latter was to be expected based on the discussion in my previously referenced article "True or False? Adding Fat to A Carby Meal Lowers Insulin Response" | read more).

Significant differences for the insulin response were observed for the white rice + chicken meal, where the insulin response was significantly higher compared to the white rice only (+22%), as well as the rice with + vegetable meal, where the insulin response was significantly lower compared to the white rice only condition (-16%).

The combination of foods determines the GI of the meal

Based on the classic equation that's usually used to determine the glycemic index of a meal (Hätönen. 2011), Sun et al. calculated the predicted glycemic of the five test meals and compared it to the actual glycemic index (GI) that was calculated based on the measured glucose and insulin response of the subjects.

Figure 2: Predicted and measured glycemic index as well as measured insulinemic index of the meals (Sun. 2014)

As you can see in Figure 2, the comparison yields an unsurprising result. As it's usually the case, when simple equations are used to predict physiological effects, the real GI values were significantly different from the calculated ones and  - significantly lower, that is. Accordingly, the meal with the least impact on postprandial glycemia and a comparatively low insulinemic effect is the one containing rice, fat, chicken and veggies - in other words, the complete meal. 

Suggested Read: "Get Your Protein, Veggies & Fruits and Get Them Regularly: High(er) Meal Frequency (6 à Day) + High(er) Protein Diet Support Weight & Fat Loss on a Diet." | read more

Bottom line: While the importance of the glycemic index (GI) has long been totally overrated, there is accumulating evidence that high postprandial glucose levels are a significant contributor to increases in cardiovascular disease risk even in healthy individuals (Einarson. 2011; Mah. 2011). Against that background the results of this recent trial support my previous recommendation to consume balanced meals containing protein, fat and carbohydrates, instead of no-fat or no-carb meals.

In contrast to what the "paleo hypothesis" and the notion that our ancestors would not have collected some berries or boiled some rice to have it alongside the chicken they just caught would say, the contemporary scientific evidence indicates that we are well equipped to handle complex meals, as long as they don't contain exorbitant amounts of fat and carbohydrates.

One thing we should not forget, though, is that the 50% discrepancy between the calculated and real glycemic index of the "complex" test meal (four ingredients is not exactly "complex", actually) suggests that one of the reasons that many of the previous studies failed to detect a meaningful association between the (obviously calculated) GI of an individuals diet and his / her cardiovascular or diabetes risk may be that the data the scientists used was similarly inaccurate as the predicted glycemic indices of the test meal in the study at hand | Comment on Facebook!

References:

• Hätönen, Katja A., et al. "Protein and fat modify the glycaemic and insulinaemic responses to a mashed potato-based meal." British Journal of Nutrition 106.02 (2011): 248-253.
• Mah, Eunice, et al. "Postprandial hyperglycemia impairs vascular endothelial function in healthy men by inducing lipid peroxidation and increasing asymmetric dimethylarginine: arginine." The Journal of nutrition 141.11 (2011): 1961-1968. 
• Sun, Lijuan, et al. "Effect of chicken, fat and vegetable on glycaemia and insulinaemia to a white rice-based meal in healthy adults." European journal of nutrition (2014): 1-8.
• Wolever, T. M. S. "Is glycaemic index (GI) a valid measure of carbohydrate quality&quest." European journal of clinical nutrition 67.5 (2013): 522-531.

Nutrition Research Update: Meal Timing & Energy Intake, Full Fat Dairy for Zero Fat Waist-Lines, D-Sorbose for Glucose Control, Broccoli for Your Brain & More

From Meal Timing Over Broccoli & Full-Fat Dairy to Anti-Diabetic Sweeteners

Based on the number of visitors you like a number of short news that will bring you up to speed on a certain topic better than a longer in-depth analysis of just one study. This and the fact that the number of recent papers that would be worth being discussed at length is not exactly huge are the reason today's SuppVersity article falls into the "short news" category again.

Basically the title says it all. All of the individual items in today's news article are from the latest issue of Nutrition Research and thus related to the effects the stuff that enters your body through your mouth is going to have on your health and overall well-being.

You can learn more about meal frequency at the SuppVersity

Grazin' Bad For the Obese!

Breakfast Keeps You Lean?!

Frequent Protein Consumption

Myth: Few Meals More Bodyfat

8 Meals = Stable, But High Insulin

Int. Fasting & Exercise

• Meal timing matters, but only because it has a significant effect on the amount of food we eat. According to the latest study by Kathryn J. Reid, Kelly G. Baron, and Phyllis C. Zee, factors that correlate with an increased energy intake in 59 individuals, whose rest/activity patterns were assessed using 7 days of wrist actigraphy, and whose caloric intake was evaluated using 7 days of diet logs, are:
  • eating more frequently , 
  • later timing of the last meal, and 
  • a shorter duration between last meal and sleep onset
  Again, none of these factors will mechanistically make you store more body fat. What they will do, however, is to make you eat more. Basically this is also what the scientists imply, when they say that "In a mediational model, eating frequency explained the relationship between eating closer to sleep onset and total caloric intake" (Reid. 2014).

  

  Table 1: Associations between total calories, BMI, meal timing, meal frequency, and measures of sleep (Reid. 2014)

  It is thus not, as you may assume based on the latest studies on the intricate relationship between meal timing and the workings of your biological clock, the timing that makes late eaters more prone to obesity, but simply the fact that they're eating more than the early birds. 
• Whole fat dairy intake is associated with lower obesity risk, findings from the Observation of Cardiovascular Risk Factors in Luxembourg study show. Bear in mind that we are dealing with observational data with all its usual flaws and shortcomings, before you start shoveling down extra amounts of whole fat dairy or throw all your low fat dairy products out of the window.

  

  Figure 1: Multivariate adjusted (Model 1: M1 | Model 2: M2, details see text) difference in risk of being abdominally obese (WC ≥102 cm for men and 88 cm for women) in men and women consuming 3 vs. 1 serving of the given type of dairy per day (Crichton. 2014).

  Although the data in Figure 1 has been adjusted for age, education, sex, smoking, physical activity (in min/wk), total carbohydrate (in g/d), total protein (in g/d), total fat (in g/d), total fiber (g/d), alcohol (in g/d), calcium (in mg/d), and total energy intake (in kcal/d), and in model 2 even for HDL (in mg/dL), LDL (in mg/dL), triglycerides (in mg/dL), and systolic and diastolic BP (in mm Hg), this is still statistical shenanigan and could well be messed up by a correlation between being fat and choosing fat foods in the (false?) believe that they would help you lose weight. 
• D-sorbose as an anti-diabetes sweetener. In an attempt to develop d-sorbose as a new sweetener that could help in preventing lifestyle-related diseases, scientists from the University of Nagasaki Siebold investigated the inhibitory effect of d-sorbose on disaccharidase activity, using the brush border membrane vesicles of rat small intestines - put simply they checked if d-sorbose would inihibt the breakdown of disaccharides into monosaccharides and thus have the ability to slow down the absorption of glucose from "complex" carbs.

  

  Figure 2: Effects of adminstration of sucrose, the same amount of sucrose and + 10% d-sorbose or l-sorbose on the glucose and insulin response in rodents (Oku. 2014)

  I've marked the "benefits", i.e. the decrease in blood glucose (left) and the reduced insulin spike (right) in Figure 2. As you can see the effect is - at least in rodents - physiologically relevant, so that it is reasonable that Oku et al. assume that
  

  "[...] d-sorbose might also suppress postprandial elevation of levels of glucose and insulin due to ingestion of sucrose or maltose in humans and could be used as a sweetener that may reduce risk for lifestyle-related diseases but requires more research" (Oku. 2014).

  In view of the fact that the technology that is necessary to produce large amounts of d-sorbose has become available only relatively recently it is yet unlikely that you will be able to buy this stuff at the health food store next door, already.

• 

  Green veggies like broccoli have also been shown to reduce postprandial glycemia + insulin and noost the production of the anti-obesogenic satiety hormone GLP-1 | learn more

  Broccoli may ameliorate "brainflammation" in the eldery. That's at least what the latest rodent study from the University of Illinois would suggest.
  
  The study that was conducted by Brigitte E. Townsend, Yung-Ju Chen, Elizabeth H. Jefferya, and Rodney W. Johnson showed marked reductions in age-elevated cytochrome b-245 β, an oxidative stress marker, and reduced glial activation markers in aged mice who were fed a diet containing 10% broccoli diet for 28 days. Overall the effects are obviously modest; and yet, the study still provides good evidence to keep broccoli on your "foods I consume regularly" list.

Does eating veggies reduce inflammation? Yes, it does, 8 servings per day will significantly reduce CRP (Watzl. 2000), 68g of avocados will reduce IL-6 & NF-kappaBeta (Li. 2013), high intakes of alpha- and beta-caro- tene containing foods is associ- ated with decreased coronary heart disease risk and CHD mortality (Osganian. 2003 ; Bujisse. 2008), tomatos may protect against prostate cancer (Etminan. 2004), tomato juice makes LDL molecules resistant to oxidation (Upritchard. 2000), toma- to paste protects your skin from UV radiation (Rizwan. 2011), etc.

You want more? Well I have another study for you. One that attempts to explain why fruits an veggies in general and plant carotenoids in particular are good for you. It's a study from the Environment and Agro-biotechnologies Department in Luxemburg (Kaulmann. 2014) that analyzed the effect of carotenoids on intracellular signaling cascade and the corresponding effects on gene expression and protein translation and found that (1) carotenoids are able to interact with the nuclear factor κB pathway and thus inhibit the downstream production of inflammatory cytokines, (2) carotenoids can block oxidative stress by interacting with the nuclear factor erythroid 2–related factor 2 pathway and activating phase II enzymes and antioxidants, such as glutathione-S-transferases, and concludes that we (3) still have an incomplete understanding of what exactly carotenoids and other phytochemicals can do for our health | Any comments? If so, leave them on Facebook!

References:

• Buijsse, Brian, et al. "Both α-and β-carotene, but not tocopherols and vitamin C, are inversely related to 15-year cardiovascular mortality in Dutch elderly men." The Journal of nutrition 138.2 (2008): 344-350.
• Crichton, Georgina E., and Ala'A. Alkerwi. "Whole-fat dairy food intake is inversely associated with obesity prevalence: findings from the Observation of Cardiovascular Risk Factors in Luxembourg study." Nutrition Research (2014). 
• Etminan, Mahyar, Bahi Takkouche, and Francisco Caamaño-Isorna. "The role of tomato products and lycopene in the prevention of prostate cancer: a meta-analysis of observational studies." Cancer Epidemiology Biomarkers & Prevention 13.3 (2004): 340-345.
• Kaulmann, Anouk, and Torsten Bohn. "Carotenoids, inflammation, and oxidative stress—implications of cellular signaling pathways and relation to chronic disease prevention." Nutrition Research (2014).
• Li, Zhaoping, et al. "Hass avocado modulates postprandial vascular reactivity and postprandial inflammatory responses to a hamburger meal in healthy volunteers." Food Funct. 4.3 (2013): 384-391.
• Oku, Tsuneyuki, et al. "D-sorbose inhibits disaccharidase activity and demonstrates suppressive action on postprandial blood levels of glucose and insulin in the rat." Nutrition Research (2014). 
• Osganian, Stavroula K., et al. "Dietary carotenoids and risk of coronary artery disease in women." The American journal of clinical nutrition 77.6 (2003): 1390-1399.
• Reid, Kathryn J., Kelly G. Baron, and Phyllis C. Zee. "Meal timing influences daily caloric intake in healthy adults." Nutrition Research (2014). 
• Rizwan, M., et al. "Tomato paste rich in lycopene protects against cutaneous photodamage in humans in vivo: a randomized controlled trial." British Journal of Dermatology 164.1 (2011): 154-162. 
• Upritchard, JANE E., W. H. Sutherland, and J. I. Mann. "Effect of supplementation with tomato juice, vitamin E, and vitamin C on LDL oxidation and products of inflammatory activity in type 2 diabetes." Diabetes care 23.6 (2000): 733-738.
• Watzl, Bernhard, et al. "Prolonged tomato juice consumption has no effect on cell-mediated immunity of well-nourished elderly men and women." The Journal of nutrition 130.7 (2000): 1719-1723.

Conventional vs. Organic: It's Not About Getting More, But Getting Less For Your Money. Less Pesticides, Dioxins & Co

Image 1: The Ökomonitoring program took a very different approach to the question whether or not organic products are worth the extra cost, they did not look for the additional edge, but rather the "subtractive edge", if you will, and tried to answer the question: "Can we even produce 'organically' in an increasingly polluted environment"; now ten years after the program started the answer appears to be "Yes!" (MLR. 2012a)

"Organic produce is no better than conventional! You are being ripped off!" Statements like this have made the headlines in the past couple of days and many people (obviously not you, though!) are scandalized or shaking their head haughtily uttering things "I knew it, and that's why I always buy the cheapest..." What both groups are missing, though is the simple fact that the question the scientists posed, or rather the question the journalists put to the forefront, i.e. "Are organically produced fruits and vegetables more nutritious?", is nonsensical, because it would imply that the absence of certain chemical agents and production methods would increase the amount of nutrients a plant puts into its fruit, leaves, roots or whatever. Since I have discussed this with my friend Carl Lanore on yesterday's joint SHR + SuppVersity News Round Up pretty extensively (in fact so extensive that we could not cover the other topics I had lined up - sorry for that, folks!), I won't go into more detail on that here, but simply repeat that the fallacy of this approach was part of my reasoning not to bore you with write-up / comment #5325 published that's been published on the bazillion of blogs within the past couple of days, but rather give you the long and short of a governmentally subsidized program that's been running for 10 years, now, here in Germany: the Ökomonitorin program of in Baden-Württemberg (this is one of the individual states here in Germany).

It's not about what's in there, but about what is not!

The researchers who are mainly working at the University of Stuttgart set out with a whole different research question than most of their colleagues. Rather than trying to answer loosely defined questions such as "What's better: Conventional or organic", they wanted to know whether or not it would even be possible to "produce organic" in an environment that is already profoundly polluted; and though I don't want to give away too much in advance, after 10 years and ten-thousands of samples of organic and conventional fruits, vegetables and animal products being analyzed the answer is "Yes it is!"

"Organic fruits and vegetables had on average 180x lower pesticide content than conventional products; and only 5% of the samples from organic produce were objectionable."

That's the conclusion the researchers in the 10-years special report that has been published in July 2012 (MLR. 2012b). Since I know that you don't content yourself with universalities like this (otherwise you would hardly be here ;-), I would like to invite you to let me walk you through some of the detailed results of the latest data from 2011, although this may not be the exact same goods you have (or haven't) been buying in the course of the last year (I just checked: Only ~6% of you are actually from Germany)

The good the bad and the equally ugly

While the general trend that emerges does in fact speak in favor of the organic products, a brief look at the data in figure 1 should suffice to see that despite the fact that the number of offenders, i.e. products with pesticide residues above the maximally allowed threshold is close to zero, even organic produce is far from being pesticide free.

Figure 1: Percentage of conventionally and organically produced products with detectable (those did not have to be above the allowed threshold levels!) pesticide residues (data based on MLR. 2012a)

Of all the categories I picked when I compiled figure 1 there are however four product categories that caught my eye immediately, because the "organic advantage" as you may call it, is particularly small, here: Wine, plant oils and processed fruit and vegetables (the latter category included frozen, usually relatively pesticide free, but also canned food and dried foods, as well as fruit jars etc.). Intriguingly, in all of those four the pesticides could (and in the case of the Wine, the researchers even proved that) have gotten into the food-chain during the processing / manufacturing process, as well - in other words processed and organic tend to be contrastive pairs.

Figure 2: Percentage of products with pesticide levels above the allowed threshold (data based on MLR. 2012a)

When it comes to the actual "offenders", i.e. those products with levels above what is officially allowed, here in Europe, there are actually seven of which I feel that they really stand out (one for each day of the week, isn't that great?):

Mothercorn, the "abortion fungus" of the middle ages, the first source of LSD and the result of inappropriately stored and subsequently moldy grains / flour being used in the production of breads, is a potential cause of auto-immune diseases and lethal toxicities.

The mothercorn (Claviceps purpurea) content [µg/kg] of multi-grain breads with rye and wholemeal rye bread (please mind the leap on the primary axis; data based on MLE. 2012a)

The ingestion of 2 mg of mothercorn does already lead to adverse reactions which range from nausea over headaches, and cramping to a loss of sensation in the extremities and vascular occlusions (the latter will also arise from chronic low-grade intoxications)- in pregnant women it will induce contractions of the uterus and spontaneous abortion. The ingestion of 5-10g of the ergot-alkaloids from the fungus kill an adult man... not exactly what you want to have in your bread, right? Not even in "harmless quantities" - which is what even the worst offenders would have to be considered, still.

• the processed foods - irrespective of whether you buy veggies or fruit, you can be sure that the contamination raises with every processing step; be smart not lazy and buy whole foods, learn how to prepare them and cook for yourself
• cereals - 3.4% of the "oh so healthy superfoods", of which at total 72% of the conventional and 36% of the organic ones contain pesticides, are also on the list of items even the European officials suggest you should better not eat, if you don't want to become sick
• legumes - another favorite of mainstream dietitians are not just among the worst offenders (24% of the conventionally produced legumes contain pesticides above the tolerable limit), they are also the only product where even the organic variety is not suitable for human consumption in 11% of the cases and as if that was not enough, the number of substances above that threshold amounts to 17 compounds in the conventional and 3 substances in the organically produced legumes
• leafy greens - the health food per se may not be among the worst offenders but in those 6.7% of the samples that had pesticides above the the threshold level, the scientist were able to identify 27(!) different pesticides (note: not all pesticides were found in all samples and the worst offenders were not broccoli & co, but rather salads)
• ginger (=ingwer)- the conventional variety something many people use to improve their health had higher than tolerable levels in 12.5% of the cases; a health food "gone unhealthy", if you will
• berries - they may not be among the worst offenders, but they are "versatile": With 5 different pesticides in the samples the scientists analyzed they can't compare with the processed veggies with 45 different pesticides, but are doing quite "well"
• exotic fruit and citrus fruit - while with them the conventional farmers obviously assume that the consumer would throw away the peel anyway; or, and this segues right into our next topic, there are no governmental controls and regulations in place; after all, you should be aware that Germany is not exactly the country to grow "exotic fruits" ;-)

If we seize on the notion of "it's not us, it's only the others that contaminate their produce, ship it to Europe (or the US) and poison us", we must however realize that things aren't so easy as they seem: While the German organic produce may in fact be the less polluted one, neither the Israelis nor the South Africans or Moroccans, but rather our European friends, the Italians are trying to poison us ;-)

Figure Y: "Worst offenders" statistics for the countries of origin of organic produce (based on MLR. 2012b)

Now, all jokes aside, it is simply not possible and probably also highly un-rewarding to replace one prejudice, i.e. all organic produce is good with another more sophisticated one such as all organic produce from Germany is good and everything from Italy, Egypt and Greece is poison. Therefore, it is probably also not so important that the intricacies of these statistics are meaningless for the majority of you who are (I just checked) US residents and not among the 6% "resident" (=German) SuppVersity students ;-)

Organic = Say no to GMO!?

With the different legislative situation here in Germany, the quantitative data on GMO "contamination" in figure 3 is probably likewise irrelevant for many of you, but with the production of GMO corn being banned, here in Germany, it does give you a sneak peak on what can happen if the government is willing to act on behalf of its people (the majority of Germans is against GMO) instead of the industry (in all fairness it must be said that it is the US and not the European, let alone the German agrar-industry that's constantly trying to push GMO corn and other produce into the German market).

Figure 4: Relative percantage of soy and soyproducts that has been genetically modified (MLR. 2012b)

Even among the conventional produce, the number of outliers was small - roughly 5% of conventional products contained <0.1% corn from genetically modified plants - a result which is probably also to be accounted for by the awareness of the industry that they will have to throw all their produce away once the GMO-skeptic consumers realize that product is contains significant amounts of genetically modified plants.

The data in figure 4 does yet also show that things look different for soy products, most of which are imported from countries where the production of GMO foods is actually allowed (like the US ;-) and even non-GMO crop can be exposed to cross-contamination. If we take a closer look and discard the annual variations, it does yet become obvious that the GMO content of organic products is just as their pesticide content still much lower than it is in conventional ones. What is pretty troublesome, though, is that in 2011 25% of the products that are advertised as "GMO free" contained small amounts (<0.1%) of genetically modified soy - for you, my American friends this means: Having a label alone does not protect you from "GMO fraud" ;-)

Eggs, salmon, animal productts and other notable observations and changes from 2002-2012

Before I'll conclude this post with a couple of notes on trends and general observations the scientists who have been working on the Ökomonitoring program over the past 10 years made and let you make up your own mind of "whether or not you feel that getting less is worth paying more", let me briefly address the issue of dioxin-laden organic eggs Carl and I have been talking about, yesterday, already:

Image 2: If you have not done so, already, I highly suggest you read my previous post "Urban Gardening: 12x More Cadmium in Your Tomatoes Than in the Conventional Produce? Plus: Domestic vs. Foreign - What's Healthier?". After all, your own organic tomatoes and other produce can be effected by the environment in which you grow them, as well.

• Not just organically produced eggs, but also organically produced salmon have on average higher levels of DDT, PCB and total dioxins (TEQ) and HCB, DDT2, PCB 153, Dieldrin, Endosulfan, Chlordan, Toxaphen, Tribromanisol, PBDE, respectively (note: wild salmon is almost free of any of the latter!)
• Those contaminations are not brought about by what the farmers do, but rather what they didn't do, i.e. make sure that their free ranging hens are not running around on toxic soils and their fish are not swimming in a toxic sea - and this is where the initial research question of the Ökomonitoring program, "Can we even produce organically?", must be answered with a somewhat shabby: "It depends" and the one parameter it depends on is the environment, to which the animals (and to a much lesser degree, the crop) are exposed
  

Now, the implications of this are not that all organic animal products are worse than their conventional counterparts (in fact the number of products without any residues is larger for the organic products, unfortunately those products which are contaminated contain much higher levels!), but rather that you have to be choosier and try not to rely on the label "organic", if you know your local farmer and trust him, you may be better off buying his non-organic eggs that those from an organic farm on contaminated land...

Find out if your area has contaminated soil by using the MyEnvironment search engine at epa.gov! Enter your area code and get the result right away. If you type in "Bronx New York", for example, you will learn that the major risk factor from air pollution is formaldehyde, that there are two final NPL sites and so on and so forth (thanks to Carl Lanore and Alisa Profumo for pointing this out on today's Casual Friday).

But enough of that let's wrap it up for today, with a couple of more or less unrelated, but interesting facts, the first of which is so important that I decided to repeat it, although I mentioned it at the beginning of the article, already:

What is Furan? Furan is a heterocyclic compound that has originally been used in the chemical manufacturing industry. It does however also occur during the combustion of coal and is a component of tobacco smoke, as well as in a number of heat processed food items such as canned and jarred foods and coffee (FDA. 2004). Furan is carcinogenic to rats and mice and was classified as ‘possibly carcinogenic to humans’ (International Agency for Research on Cancer, 1995; see as well Cordelli. 2010; Chen. 2012)

• on average 180x lower pesticide residues in organic fruits and veggies - that's the astonishing result after 10 years of Ökomonitoring
• no = ZERO pharamcologically active substances in any of the testes organic produces
• antibiotics residues in organic honey were reduced from 23% to 0% from 2003 to 2005; no complaints thereafter
• the mycotoxin load is about equally high in conventional and organic produce
• No significant differences in terms of organic contamination and pesticide residues exist between animal products; the dioxin load in eggs free ranging hens and organic salmon are exceptions to this rule (while levels spiked in 2009, when "buying organic" really took off over here and more and more farmers started producing "organic eggs", the levels have been slightly declining over the past years)
• the way organic coffee is roasted leads to increased furan levels in organically produced roast coffee
• the amount of acrylamide in cookies is equally high in organic vs. conventional products, the in organic chips is higher and the number of samples with levels above the 1,000µg/kg threshold is higher as well
• no differences were found in terms of trans fatty acids in ready-made meals
• organic softdrinks are free of preservatives
• no artificial colorings in organic sweets

Now it's up to you - organic, yes or no? And remember: We cannot always make everything 100% right, but that does not mean that you should give up trying.

References:

• Chen T, Williams TD, Mally A, Hamberger C, Mirbahai L, Hickling K, Chipman JK. Gene expression and epigenetic changes by furan in rat liver. Toxicology. 2012 Feb 26;292(2-3):63-70.
• Cordelli E, Leopardi P, Villani P, Marcon F, Macrì C, Caiola S, Siniscalchi E, Conti L, Eleuteri P, Malchiodi-Albedi F, Crebelli R. Toxic and genotoxic effects of oral administration of furan in mouse liver. Mutagenesis. 2010 May;25(3):305-14.
• Food and Drug Administration. Exploratory Data on Furan in Food, vol. 2011. 2004 < http://www.cfsan.fda.gov/∼dms/furandat.html >
• International Agency for Research on Cancer. Summaries & Evaluations, vol. 2011. 1995. 
• Ministerium für Ländlichen Raum, und Verbraucherschutz Baden-Württemberg (MLR). Ökomonitoring. Ökomonitoring Bericht für das Jahr 2011. June 2012b.
• Ministerium für Ländlichen Raum, und Verbraucherschutz Baden-Württemberg (MLR).Ökomonitoring. 10 Jahre Ökomonitoring. 2002 – 2011. Jubiläumssonderausgabe. June 2012b.

EPIC Study Says: Vegetables, Fish, Dairy, Pasta & Rice Reduce, Softdrinks, Processed Meat, Margarine, Spirits and Potatoes Increase Waist Circumference - Really!?

Image 1: The EPIC project unites scientists
from all over Europe (EPIC, IARC. 2011)

I don't know whether it is a good idea, for an anti-epidemiologist like me (I mean, come on, epidemiology vs. controlled experiments is like astrology vs. astronomy) to post this, but a 13-year (1992-2005) meta-analysis (Romaguera. 2011) of data from 48,631 men and women from 5 countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) study is probably as good as as epidemiology can ever get and with scientists from 12 different institutes all over Europe, there is at least some hope that the results of their investigation into the association of food groups/items consumption "on prospective annual changes in 'waist circumference for a given BMI' (WC_BMI), prox for abdominal adiposity".

Unfortunately the first of the typical shortcomings of EPIC studies (pun intended) like this becomes obvious in the previous citation, already, as the quotation marks before "waist circumference" indicate that the latter "was measured either at the midway between the lowest rib and the iliac crest (the Netherlands, and Potsdam-Germany) or at the narrowest torso circumference (the other centres)." And even worse,

at follow-up examinations, participants in Norfolk (United Kingdom) and Doetinchem (the Netherlands) were measured by trained technicians using the same protocols as at baseline, whereas other centres provided self-reported data.

I guess you can imagine how "exact" these waist circumference are - if not, try and "measure" your personal waist circumference, you will be astonished how easy it is to "diet down" from 35" to 32"... it's a pitty that this kind of 'weight reduction' is not sustainable ;o)

Be that as it may, it argues in favor of the scientists that they did a validity test with 408 men and women from the Danish cohort beforehand and it turned out that "a high correlation between the self-reported and technician measured WC was found". Furthermore, the scientists were able to extrapolate association with baseline BMI and used these later in the regression analysis to make up for potential measuring "mistakes" on part of their subjects. If we thusly assume that at least this part of the data is reliable - I don't think I have to go into any detail as far as notoriously inaccurate food frequency questionnaires are concerned - the study provides some tangible insights into the influence the eating habits of the general population has on the accrual / loss of body fat.

Figure 1: Association (expressed as beta² coefficients, left axis) of certain foodstuffs and beverages (daily consumption in grams, right axis) with increases (positive beta²) and decreases (negative beta²) in waist circumference in 48,631 subjects from the EPIC-DiOGenes project (data adapted from Romaguera. 2011)

If you have a closer look at the data in figure 1, it's quite easy to recognize the major offenders, if you compare the association strengths (beta²) of a given food with the total amount of this foodstuff/beverage in g/day the men and women in the EPIC-DiOGenes project consumed. High beta² values indicate a positive association, which means that study participants who report (!) that they eat much of this food / drink much of this type of beverage, were more likely to increase their waist circumference.

Image 2: If you have any interest in milk, colostrum or dairy in general, make sure you read my recent write-up on milk and milk consumption!

Now, while spirits may have an even higher association with abdominal adiposity than soft drinks, the overall contribution of Jack Daniels and Co to the obesity epidemic, which has a similar handle on Europe as on the US, is nevertheless negligible, because even men "booze" way to seldom to get fat just from booze. On the other hand, the negative association of fish (beta²=-0.05) and waist circumference is much stronger than that of milk, but since fish consumption is equally low for both men and women, chances are that, overall, milk (beta²=-0.01) may contribute just as much or even more to keep (at least some of) Europeans, who love their milk (you can read more on milk if you follow the link beyond image 2) and despise fish, from bursting out of their pants and skirts than fish does, despite having the higher and thus less beneficial beta² coefficient.

I bet, some of you are just about to freak out that both "vegetable oils", as well as pasta and rice and (worst of all) breakfast cereals are associated with reductions in waist circumference. At least in the eyes of the paleo-cultists out there, this may disqualify the study as devil's work ;-) People like Robb Wolf or Matt Lalonde, whose pointed analyses go beyond the common black-and-white cave-paintings you will find on the bazillion of paleo-blogs out there, would yet notice that the men and women in the study actually consumed relatively low amounts of these foods. Roughly 63g of rice and pasta for men and 52g for women is certainly a tolerable amount. And to be honest, I have not seen anybody die from a well filled tablespoon of vegetable oil per day, either ;-)

Almost "experimental" seems the last finding of the study I want to mention, which is the (calculated) effect the replacement of (-100kcal energy from) soft drinks, margarine, processed meat and white breads (the major offenders) with either (+100kcal from) dairy or fruits would have on the changes in waist circumference in the course of one year.

Figure 2: Model calculation of the beneficial (lower beta² coefficients) effects of iso-caloric (100kcal/day) replacements of soft drinks, margarine, processed meat and white bread by fruits or dairy (data adapted from Romaguera. 2011)

As the data in figure 2 goes to show the effect the statistical model predicts that the effects of fruit would be more profound... this, however, is something I dare question, simply because the different macronutrient composition of dairy (moderate protein, moderate fat, relatively low carb) vs. fruit (no fat, no protein, high carb) simply forbids such statistical thimblering that neglects the macronutrient composition and focuses solely on the caloric value... ahh, one last word: Whenever, this crucial distinction between eating calories and eating food (I am starting to think that maybe some of the scientists actually eat calories?) will reach mainstream science, I will immediately let you know ;-)

Urban Gardening: 12x More Cadmium in Your Tomatoes Than in the Conventional Produce? Plus: Domestic vs. Foreign & Conventional vs. Organic - What's Healthier?

Image 1: Allotment gardens are the new trend among young families in Germany, 45% of the 1,000,000 allotment gardens that were previously the territory of stuffy men and their garden goblins are already in their hands - that equals a total "acreage" of 21,000hectar - let's hope none of these gardens is right next to a street.

Those of you who have listened to the "Urban Gardening" episodes Alisa Profumo did on Super Human Radio back in 2011 (click here to download Part I and Part II) may remember that it is not impossible to grow your own vegetables, herbs and more - and that not just in a large garden. In fact, "urban gardening", which has here in Germany long been regarded as antiquated and "for grandmas and grandpas only" has become fashionable again, as more and more people enjoy the comfort of "knowing what they eat". Unfortunately, a recently published German study shows that believing does not mean knowing; or do you believe that people who knew that their homegrown tomatoes have 5.7x more nickel, basil more than 5.4x more anorganic chromium and their carrots 4.2x more cadmium than their conventionally grown counterparts from the supermarket around the corner would still not unsettle their faith in the general and unquestionable superiority of home-grown produce?

From the exhaust pipe into your garden and from your garden into your mouth :-(

Just to make sure that we understand each other: This is no anti-gardening post, it is just a brief reminder of the differences between hearsay and nostalgia, on the one hand and facts and reason, on the other. In that, it is very reasonable to assume that the constant pesticide assault is a problem, it is however not reasonable to assume that veggies and herbs you grow in the toxic environment of a major city like Berlin or its rural outskirts are per se "pollutant free".

Figure 1: Main importers of vegetables, root and tubers in 2011 (ITC calculations based on UN COMTRADE statistics)

Did you know that Katz et al. have shown in 2008, that...

• the pesticide residues in domestic (US) produce (fruits and vegetable) were significantly higher for 11 pesticides while imported exposures were higher for the remaining four. 
• all five pesticides that were found in potentially hazardous (yet on a per serving base still licit level) were the higher in US than in imported produce
• the mean daily exposure estimate for one pesticide, methamidophos, was above the reference dose for domestic fruits and vegetables while slightly below the reference dose for imported fruits and vegetables

... probably not, right? If you want to avoid pesticides, all-together it is advisable to chose organically grown produce, anyway - also for it's slightly higher nutrient content (see next infobox)

This is all the more true in view of previous exploratory studies, which have already shown that horticultural crops in urban or peri-urban areas are generally exposed to a higher level of pollutants of both inorganic and organic origin than the conventional produce they are supposed to replace (Shinn. 2000; Alloway. 2004). And as Ina Säumel and her colleagues point out,

"the contamination of urban horticultural products can exceed the precautionary values, and a dietary exposure to trace metals can result in significant human health risks." (Säumel. 2012)

That said it was only logical that the researchers from the Technische Universität Berlin and their colleague from the Botanical Garden of the Khmelnitskij National University in  Khmelnitsky, Ukraine, set out to compare the positive view the public has on urban- and peri-urban gardning (according to a survey among gardeners, producing "fresh and healthy fruits and vegetables" is one if not the main motivations for gardening; cf. ) to the actual level of potentially hazardous substances in their produce.

The samples were collected from 28 randomly chosen sites within inner city neighborhoods in Berlin, Germany. As the authors point out,

"[t]hese sites represent a mixture of different local settings of horticultural plantings within Berlin’s centre  and were characterized according to the following parameters: (a) overall traffic burden (otb) within a radius of 1 km around planting sites [...] (b) traffic burden of the nearest road per day [...], (c) distance to nearest road (d; in meters); and (d) presence or absence of barriers between planting sites and next street which might reduce airborne pollution." (Säumel. 2012)

In combination with the data on the planting styles of the individual produce this allowed for a very detailed analysis of the confounding factors that influenced the the zinc, copper, lead, cadmium, chromium and nickel concentrations of the 12 different horticultural crop species (tomatoes, green beans, carrots, potatoes, kohlrabi =Brassica oleracea var. gongylodes, white cabbage, nasturtium, parsley, chard, basil, mint, thyme).

Figure 2: Trace metal content of 12 different horticultural crop species from 28 randomly chosen sites within inner city neighborhoods in Berlin, Germany; data expressed relative to conventionally produced produce from the local supermarket, the dotted black line indicates the respective 100% content of the conventional produce - everything thats above this "demarcation line" has more, everything below less of the metal (calculated based on Säumel. 2012)

If you take a look at the results you may initially be shocked - 12x more cadmium in "home-grown" tomatoes than regular produce? The currently allowed maximal level of this toxic trace metal depends on the respective legislation (I guess I don't have to rant about what those differences tell you about the arbitrariness of "allowances" & co) and is in the range of 0.1mg/kg for vegetables with 0.12mg/kg the mean content is thus already right at the red line of the official "danger zone" - the maximal detected value of 0.79mg/kg is 7.9x higher and certainly no healthy alternative to the conventional supermarket tomatoes with 0.01mg/kg (i.e. 10x below the tolerable limit) of cadmium in them.

Figure 3: Soil, overall traffic burden and the distance to the nearest road are all confounding factors that will influence how much unwanted trace metals your pesticide-free produce will contain.

As you may already guess, both the overall trace metal load as well as the high discrepancies between individual vegetables and herbs are largely dependent on their individual traffic exposure with zinc, lead, nickel and chromium showing statistical significant correlations with the overall traffic burden and lead, chromium and cadmium with the distance to the nearest road.

Plant away from roads and/or behind fences or walls + other things to protect your crops

Did you know that one of the latest meta reviews confirmed the superiority of organic vs. conventionally grown produce as far as its nutrient content is concerned? According to Hunter at al. the nutrient content of organically grown vegetables was 5.9% higher, that of legumes 5.7% (for fruits the 6.5% difference did not reach statistical significance; cf. Hunter. 2012). There is however a significant difference between screened and non-screened trials, with the former having a clear-cut bias towards an even higher difference than the latter (mean difference 8%). It is however at least questionable how valuable a classification like this is, when the "superior" mineral content of organically grown veggies, for example, is mediated among others by a statistically significant +6% higher phosphor content, the level of calcium and magnesium, however is only non-significantly higher (0.6% and 3%, respectively).

Aside from planting further away from, or next to low traffic streets, placing your plants behind fences, walls or other protective barriers can be a valid method to reduce the trace metal content of your crop. Moreover, Säumel et al. point out that regardless of the traffic burden,

"[...]the vegetables planted in urban soil beds were less likely to have lead values above the critical values than vegetables planted in pots or beds that had been supplemented with commercial garden soil. This might result from the use of compost, which increases metal solubility, but more research is needed to reveal underlying causes as we could not analyse soil trace metal contents." (Säumel. 2012)

This does not necessarily mean that planting in the local soil must be better, nor is it certain that the commercial garden soil was already contaminated, it should yet raise your awareness that even when you are planting outside of the 10m danger-zone of the next street in which 67% of the analyzed crop has lead values that exceeded the standards of the European Union, the lead, cadmium, nickel and what not could already be in the soil of your garden or be accidentally introduced by the commercial garden soil you bought and used to increase your produce (for tips on safer ways than the next best fertilizer from the garden center, listen to the initially mentioned gardening episodes of Super Human Radio).

Picking the right crop, such as kohlrabi, green beans or basil and installing extra fences using the back instead of the front yard are other means that would allow for "safer gardening" even in the inner city. When you are living right next to the highway, all that will yet probably be useless. I don't know if you have something like that wherever you are from, but the good old German "Schrebergarten" (=allotment garden), is becoming increasingly popular, over here - and, as I initially mentioned, not just among old stuffy men and their garden goblins; for me personally that would not be an option, but who knows, maybe it is for you?

Bottom line: Done right, i.e. not directly next to a high traffic street and without the use of standard commercial soils and fertilizers, yet fully aware that neither the "remarkable taste" of your tomatoes, carrots & co, nor being able to say "I produced it in your own garden" let alone "on my own balcony" will  protect you from the toxins that may be present in what your 100% pesticide free produce, gardening does still offer a safe and above all self-empowering alternative to buying all your goods at the farmers market, super market or wherever else you prefer to shop.

References:

• Alloway, BJ. Contamination of soils in domestic gardens and allotments: a brief review. Land Contamination and Reclamation. 2004; 12:179-187
• Burda GmbH, 1993. Wohnwelten und Gärten in Ostdeutschland: Alltagsästhetik, Wohnmotive, Wohnstile, Gartenwerte und Gartenstile in den neuen Bundesländern. ein Forschungsbericht der Burda-GmbH, Offenburg, und Sinus, Heidelberg, 108 p. (German).
• Hunter D, Foster M, McArthur JO, Ojha R, Petocz P, Samman S. Evaluation of the micronutrient composition of plant foods produced by organic and conventional agricultural methods. Crit Rev Food Sci Nutr. 2011 Jul;51(6):571-82.
• Katz JM, Winter CK. Comparison of pesticide exposure from consumption of domestic and imported fruits and vegetables. Food Chem Toxicol. 2009 Feb;47(2):335-8. Epub 2008 Nov 27. 
• Säumel I, Kotsyuk I, Hölscher M, Lenkereit C, Weber F, Kowarik I. How healthy is urban horticulture in high traffic areas? Trace metal concentrations in vegetable crops from plantings within inner city neighbourhoods in Berlin, Germany. Environ Pollut. 2012 Jun;165:124-32. Epub 2012 Mar 22.
• Shinn NJ, Bing-Canar J, Cailas M, Peneff N, Binns HJ. Determination of spatial continuity of soil lead levels in an urban residential neighborhood. Environmental Research. 2000; 81:1-7.

Study Puts "?" Behind Beneficial Health Effects of Veggies! Is There No Correlation Between Antioxidant Content & Beneficial Health Effects of Cucumber, Lotus & Rape!?

Don't obsess about "optimal" antioxidant contents, just eat your veggies!

Over the past couple of weeks, ... no actually over the past years I have repeatedly written about the concept of (mito-)hormesis and its consequences for the well-established, but not necessarily accurate free radical theory of aging (and for some people everything else). ROS, i.e. reactive oxygen species, have been established as an important signalling molecule that is - among other things - heavily involved in the insulin sensitizing effects of exercise. "Inflammation" makes muscles grow and burns body fat and the "what doesn't kill me makes me strong" principle appears to reign everywhere you look.

You can learn more about the secrets of longevity at the SuppVersity

Are You Stressed Enough to Live Forever?

Suffocated Mitochondria Live Longer

Get Lean & Live Longer With I. Fasting

Can You add 9 Years to your Life W/ Glucosamine?

5+ Tips To Live To See Your Great Grand Children

Is a Latent Acidosis Killing You Softly?

That being said, the latest study from the Institute of Health and Environmental Medicine in Tianjin, China, opens another "anti-antioxidant" Box of Pandora. One that puts a huge questionmark behind the implications of hundreds of thousands of scientific studies, when it says in it's title, already: "No correlation is found for vegetables between antioxidant capacity and potential benefits in improving antioxidant function in aged rats"

"Skin of Grape Tomatoes Contains Max. Amount of Antioxidants" - You can find this and dozens of other daily updated SuppVersity Science News on www.facebook.com/SuppVersity

This is a title that may in fact change the way we look at study results like those of a recent study by Valdez-Morales, et al. (2014) investigating the "best" = highest antioxidant tomato, the results of which you are about to find among the ~20/day SuppVersity Facebook News @ www.facebook.com/SuppVersity - don't forget to like it, or you'll miss out on the latest science news!

If the results of the study can be confirmed by an independent team for vegetables other than lotus root, rape or cucumber and if there is an identical mismatch between the in-vivo anti-oxidant capacity and the potential benefits in improving antioxidant function in (aged) humans.

This would be big and highly consequential news for nutrition experts, scientists and average Joes and Janes like you and me. Why? Well,...

• any ranking of "superfoods" that was based even partly on in vitro data derived with the good old ferric reducing antioxidant power (FRAP) assay would be invalid, ...
• every scientist who has been following up on "promising" data from FRAP assays would have been wasting his time, ...
• and you may have been eating all the wrong foods for years...

... hell no, as long as you ate your veggies over the past years, I wouldn't worry if you may have made a "suboptimal" selection (which would be different based on whatever new criteria you select).

Figure 1: FRAP value, vitamin C and vitamin E content and total amount phenolics in the powdered vegetables that were added to the rodent diets in the study at hand (Ji. 2014)

Honestly, I'd hope that you didn't select your foods only based on the orthorexic principle of maximal antioxidant content, anyways. 

Never forget the three principles of veggie eating: Variety, seasonality, colorfulness

Against that background I'd recommend you keep eating your lotus roots, if you like them, although, they have a significantly lower beneficial effect on SuperOxide Dismutase (SOD, a group of antioxidant enzymes) than rape and cucumber.

Figure 2: Serum markers of anti-oxidant status / oxidative damage after 6 weeks on the three experimental diets (Ji. 2014)

Moreover, if you look closely at the data in Figure 1+2, you will realize that lotus may suck at SOD and its ability to reduce hemolysis (the destruction of red blood cells), but will have the most profound beneficial effects on the levels of malondealdehyde (MDA), a marker of lipid oxidation, and the amount of plasma carbonyls, which have - just as in cellular regulation, aging, and disease (Levine. 2002). Just like their similarly radical cousins, carbonyls will thus play a dual role so that in the end, their reduction may not be beneficial in each and every case.

Figure 3: Blood mononuclear cell DNA damage expressed as total injury rate (%) and total tails low (% of all) in male Wistar rats on control and experimental diets (Ji. 2014)

The Take Away: Whatever the role of carbonyls, MDA & co may be and no matter what you believe which of the three tested vegetables may be the "best" one, if there is one definite message you can take home from today's SuppVersity article, it's not to overly rely on the abstract data from chemical tests the reliability of which appears to be inversely proportional to their accuracy.

Trust your instincts and go for a broad variety of vegetables. Eat seasonal! Eat colorful! And most importantly eat plenty. Optimal or not, none of the vegetables in the study at hand would harm you - all of them would help you defy diabesity and slow the aging process as best mother nature allows.

Reference: 

• Ji, Linlin, et al. "No correlation is found for vegetables between antioxidant capacity and potential benefits in improving antioxidant function in aged rats." Journal of Clinical Biochemistry and Nutrition 54.3 (2014): 198-203.
• Levine, Rodney L. "Carbonyl modified proteins in cellular regulation, aging, and disease^{2, 3}." Free Radical Biology and Medicine 32.9 (2002): 790-796.
• Valdez-Morales, Maribel, et al. "Phenolic content, and antioxidant and antimutagenic activities in tomato peel and seeds, and tomato by-products." Journal of Agricultural and Food Chemistry (2014). Accepted Manuscript.