Chromium Picolinate Worsens Insulin Sensitivity in Healthy, Non-Diabetic, Non-Obese Individuals by Up to 25%

The more supplements you take the more likely you are to get way more than the 200mcg of chromium of which previous studies have shown that they are useless for healthy people, but at least not detrimental (cf. Lukaski 1996 & 2007; Vincent. 2007). Especially people who like the  'poly-supplementary' approach are yet at risk of getting so much of a this trace mineral that it will hamper not improve their insulin sensitivity.

I don't have to tell you that you would already be dead if you were following all the bro-scientific advice that's out there on the Internet and still I usually recognize a certain reluctance to give up on what X suggests and Y has tried an what has worked so well for Z. One of the instances, where I have hitherto been missing a 100% convincing argument to argue that this is just another instance where common wisdom would in fact be better called "common stupidity" is the "insulin mimetic" or "insulin sensitizer" (or whatever your favorite bro-expert may call it) chromium picolinate. With the recent publication of the result of a study on the effects of chromium supplementation in healthy individuals there is now finally a human study that confirms that chromium, which has never been an "insulin sensitizer", but rather an "insulin release amplifier" that reduced blood glucose in diabetics by simply having them produce even more insulin is not a supplement any healthy man or woman, let alone athlete should consider a staple of his or her regimen.

The long and short: Chromium hampers insulin sensitivity in normoglycemic individuals

For their experiment lead author Umesh Masharani and his colleagues from the UCSA recruited a group of 27 non-obese, non-diabetic, healthy subjects between the ages of 20 and 50 with a body mass index of less than 27 kg/m² and <24 kg/m² for subjects with Asian heritage (the cut-off limits were set so that they would be below a BMI that has not yet been shown to be an independent risk factor for insulin resistance; cf. Clausen. 1996; Newell-Morris. 1998).

To evaluate whether chromium picolinate (ChrPic) supplements, which contributed with $150,000,000 to the revenue of the supplement industry in 1996 (Nielsen. 1996), could come up to the claims that they would exert beneficial effects on glucose tolerance and insulin sensitivity, the study participants were randomized to take either a placebo or a high dose 500µg CrPic supplement twice daily for 4 months (the dosage was selected in view of previews studies reporting greater benefits of 1,000 vs. 200mcg of CrPic in - you already guessed it - diabetic subjects; cf. Morris. 2000).

Figure 1: Insulin sensitivity measured by euglycemic clamp before and after the 16 week intervention (left); change in insulin sensitivity of the individual subjects plotted against serum chromium levels at the end of the study (Masharani. 2012)

As the data in figure 1 goes to show, the results of the CrPic intervention were more or less the exact opposite of what the ~10 million US consumers of respective supplements probably expect from the pills many of them are taking almost religiously. Despite the fact that all subjects had very low chromium levels at the beginning of the study, the previously non-significant minimally benificial relation between both serum and urinary chromium, on the one hand, and insulin sensitivity (r = 0.24, p=0.1; r=0.08, p=0.79 respectively), on the other hand, had turned into a very significant negative correlation between high(er) urinary and serum chromium concentrations and lower insulin sensitivity at the end of the 16 week intervention period (figure 1, right).

"Due to the apparent variation in the degree of chromium absorption between subjects, we examined the relationship between serum chromium and change in insulin resistance. After controlling for baseline patient characteristics, results of a multiple regression analysis showed a strong association between serum chromium and worsening of insulin–mediated glucose disposal (β= -0.83, p<0.01), where subjects with the highest serum chromium had a decline in their insulin sensitivity. To further explore the association between chromium absorption and insulin resistance, patients within the chromium group were divided (based on  a medial split at 3.10 µg/L) into a high (n=6) and low (n=8) serum chromium group [...] There were no group differences at baseline; however, at post-assessment participants in the high serum chromium group (> 3.1  µg/L) were more insulin resistant than participants in the low serum chromium group (≤3.1  µg/L) or the placebo group (p=0.02, p=0.05 respectively) (Figure 3)." (my emphases in Masharani. 2012)

Due to the fact that the scientists did not observe any differences between the placebo and low serum  chromium groups (on a side note, contrary to many other studies insulin Masharani et al. measured the insulin sensitivity in a very reliable way with an euglycemic hyperinsulinemic clamp; cf. Defronzo. 1979), the scientists also conducted a post-hoc analysis to identify potential confounding factors that may have influenced the outcome of the trial. Neither changes in triglycerides levels LDL, BMI, or truncal fat were yet associated with the differences they observed between the supplemented and non-supplemented participants. Interactions that would reduce the significance of the observed correlations were likewise absent:

"Furthermore, when changes in triglycerides, LDL, BMI, and truncal fat were individually added to the model, none were independent significant predictors of change in insulin sensitivity, and chromium absorption remained a significant predictor of reduced insulin sensitivity in each model." (Masharani. 2012)

Against that background the scientists conclude that there must be a "direct effect of chromium on changes in insulin action". A mechanism, by the way, which is totally independent of classic markers of insulin resistance such as high serum lipids and abdominal / truncal adiposity .

Being healthy is a good predictor of increased chromium absorption and more pronounced negative effects, so if you are healthy and want to stay this way don't even think of taking high dose chromium supplements.

Despite the fact that the changes in insulin resistance did not depend on changes in serum lipids and other markers of metabolic health, Masharani and his colleagues were able to show that the increase in chromium levels in response to supplementation did. With the already mentioned statistically significant correlation between increases in serum chromium levels (higher response to supplementation = higher increase), on the one hand, and the worsening of insulin sensitivity, on the other hand, this means that the healthiest subjects, namely ...

"[...] subjects with lower triglycerides, and those with lower levels of homocysteine [who had] a greater likelihood of being in the high absorption group" (Masharani. 2012)

... were at the same time those who were at the greatest risk of the ill side-effects high dose chromium supplements exert on the insulin tolerance of healthy, non-diabetic, normal-weight individuals.

No matter if it may have helped you produce insulin back in your obese days, once you have accomplished this you better avoid high dose or multiple (hidden) sources of supplemental chromium like a plague - unless you can't afford new jeans, of course ;-)

Bottom line: Unless you are not a type II diabetic or feel the urgent desire to become one, you better steer clear of exuberant amounts of supplemental chromium the RDA is enough. This is particularly true, if you are already taking a multi (which is almost guaranteed to have 200mcg in it), or any BB-style supplements. After all, "broscience" wants it that chromium is in everything that's even remotely related to insulin / nutrient uptake or whatever. With the use of only one of these products and 200mcg of supplemental dietary chromium per day, you may still argue that it probably won't do much harm. When you add another 200mcg from your "nutrient partitioner" on top of the 200mcg you get from your multi and the 200mcg of which you probably did not even realize yet that they are part of your pre-workout supplement, however, you can hardly complain about simply not being able to tolerate carbohydrates - I mean, what's your body supposed to do if you are dumb enough to believe in the promises of fat loss and lean mass increases that have been debunked in the late 1990s, already (cf. Lukaski 1996 & 2007; Vincent. 2007), and simply chose to ignore the latest scientific evidence that chromium picolinate supplements are not just useless, but actually detrimental to your health?


References:

• Clausen JO, Borch-Johnsen K, Ibsen H, Bergman RN, Hougaard P, Winther K, Pedersen O. Insulin sensitivity index, acute insulin response, and glucose effectiveness in a population-based sample of 380 young healthy Caucasians. Analysis of  the impact of gender, body fat, physical fitness, and life-style factors.  J Clin Invest. 1996;  98(5):1195– 1209.
• Defronzo RA, Tobin JD, Andres R. Glucose clamp technique: a method for quantifying insulin secretion and resistance. Am J Physiol. 1979; 237:E214–E223. 
• Lukaski HC, Bolonchuk WW, Siders WA, Milne DB. Chromium supplementation and resistance training: effects on body composition, strength, and trace element status of men. Am J Clin Nutr. 1996 Jun;63(6):954-65.
• Lukaski HC, Siders WA, Penland JG.  Chromium picolinate supplementation in women: effects on body weight, composition, and iron status. Nutrition. 2007; 23(3):187– 195.
• Masharani U, Gjerde C, McCoy S, Maddux BA, Hessler D, Goldfine ID, Youngren JF. Chromium supplementation in non-obese non-diabetic subjects is associated with a decline in insulin sensitivity. BMC Endocr Disord. 2012 Nov 30;12(1):31.
• Morris BW, Kouta S, Robinson R, MacNeil S, Heller S. Chromium supplementation improves insulin resistance in patients with Type 2 diabetes mellitus.  DiabetMed. 2000; 17(9):684–685.
• Newell-Morris LL, Treder RP, Shuman WP, Fujimoto WY. Fatness, fat distribution, and glucose tolerance in second-generation Japanese-American (Nisei) men. Am J Clin Nutr. 1989; 50(1):9–18.
• Nielsen FH. Controversial Chromium: Does the superstar minearal of the mountebanks receive appropriate attention from clinicians and nutritionists?  Nutr Today. 1996; 31(6):226–233.
• Vincent JB: The nutritional biochemistry of chromium (III). Amsterdam, Boston: Elsevier. 2007.

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

Set to Be Obese? Epigenetic Programing in Utero - The Roles of Over- & Undernutrition, High & Low Protein, Fruits, Veggies, Zinc, Magnesium, Chromium, Vitamins & More

Image 1: Your mother's diet is not the sole cause of your love handles and health problems, but it could well have tipped the scale to your fat disadvantage. Don't be resentful, but don't repeat the same mistakes, either!

While it is certainly false to assume that anyone can't help but to get obese, it's similarly hard to deny that some people just have to cut back on the coke and sweets they eat to get back in shape, while others struggle with shedding superfluous weight (=fat) and regaining their health even if they are in a reasonable caloric deficit, eat a whole foods diet and exercise regularly. "It must be in my genes!" is what you will usually hear from people on both ends of the spectrum and while the former will smile at you and grab the next best snickers bar, just "to make sure that they don't lose too much weight", the unfortunate people on the other end of the spectrum are clutching to each and every straw, or, in these days of Internet quackery, "expert" advice to finally solve their life-long misery.

In today's blogpost I want to take a brief look at the leatest research into the epigenetic realities of obesity and how those nasty love-handles you have been carrying around for years, now, may actually have been "programmed" when what is now your body was still a bunch of constantly differentiating cells.

A fetus needs more than just adequate folate (let alone folic acid)

We have known for decades, that the consequences of fetal malnurishment, i.e. the insufficient provision of macro- and micronutrients, go well beyond an increase in infant morbidity and mortality. Van Assche et al. report as early as in 1977 that fetal growth retardation (due to malnurishment or other causes) was associated with reductions in both the size and the function of the pancreas (Assche. 1977); reductions, of which Hales et al. were able to show that they can lead to glucose intolerance and hypertension later in life (Hales. 1991).

Image 2: No, no, no! Juicing your fruits and downing 5-6 apples, oranges, peaches, lemons, grapefruits or whatever in one sitting is not healthy! Neither for you, nor for your offspring!

What can you do? As I said data from human studies is scarce and mostly observational, but if you are concerned about the beta-cell autoimmunity and subsequent increases in diabetes risk of your offspring, a study from the University of Tampare suggests that it may be a good idea to eat more berries (-10% risk) and to drink more coffee (-38% risk; Virtanen. 2011). If you are afraid that your offspring may be too small, you better eat fruit and veggies instead of pills, as the consumption of the former and not the total amount of micronutrients correlates with the size of a newborn (Loy. 2011). Thusly avoiding low intakes of (leafy) vegetables and (malaceous) fruits, all you need to reduce the incidence of allergic wheeze in your offspring is to make sure you get enough chocolate (low chocolate consumption = +36% increase; Erkkola. 2012) and avoid fruit and berry juices (+40% risk increase) and and you should be good to go ;-)

The overall message should yet be: Don't stuff or starve yourself and stick to the principles of healthy living I have been trying to piece together like a puzzle in the past 727 posts and the countless comments here at the SuppVersity. This will be good for you and for your offspring!

In the last decade more and more scientists have tried to elucidate the exact mechanisms behind this metabolic deteriorations. And while the increased awareness of the importance of dietary folate is probably the most prominent results of these efforts, vitamin B9 is by far not the only (micro-)nutrient in your diet which can exert far-reaching long-term effects on your offspring. And though much of the information we have is based on rodent or epidemiological human data, I believe that it is worth considering how what you eat today, may influence the health of your children in the future:

• Micronutrient deficiency and body fat % of the offspring: In a series of studies, Rao et al. were able to show that total (-50%) micronutrient deficiency, as well as an insufficient supply of magnesium, manganese, chromium, zinc, folic acid or vitamin B12 (summary in Rao. 2012) led to statistically significant increases in body fat levels in the offspring of rats. And while the effects of maternal chromium and manganese deficiency could be corrected later in life, those that were induced by a lack magnesium, zinc and vitamin A (Ribot. 2001) in the diet of the pregnant rat dams, were permanent.
   
• Exaggerated cortisol release due to high fat diet and insufficient chromium: Both a diet insufficient in the trace element chromium (Padmavathi. 2010), as well as one of the standard "high fat diets" (30% fat; 16% protein; 37% carbs; Bullo-Cioca. 2010) increased the corticosteroid (cortisol) response to stress and thusly increased the diabetes and obesity risk of the offspring of chromium deficient or HFD significantly. Unpublished results by Roa et al. suggest that a similar increase in 11-beta-HSD (the enzyme responsible for the formation of cortisol) exist for folate and vitamin B12, as well (Rao. 2012).
   
• Cholesterol, triglycerides and other lipids: While an insufficient intake of manganese during pregnancy appears to make the offspring more susceptible to diabetes, obesity and low-grade inflammation, a profound lack of magnesium and zinc reduced the levels of cholesterol and cholesterol and triglycerides, respectively (Venu. 2008; Padmavathi. 2009).
   
• Iron deficiency results in growth retardation and brain chemistry: Pubs born to rats on an iron-deficient diet were not only smaller and had altered lipid metabolisms, they also exhibited disturbances in brain dopamine metabolism and defects in the brain myelin (fatty layer that protects the neurons) fatty acid composition (Kwik-Uribe. 2000)
   
• Reduced and exaggerated salt intake predispose to hypertension: As of late the FDA has been going back on their recommendation to avoid salt like a plague and while their reasoning was a different one, the results of a 2011 study by Kaleganova et al. confirm that both a high and a low sodium intake during pregnancy can lead to pathological changes in the kidney morpholgy of the offspring and, subsequently, to hypertension (Kaleganova. 2011)
   
• Increased susceptibility to obesity in response to high-dose multi-vitamin supplementation: Although the overall message of the above effects of nutrient-depended epigenetic programming appears to be that you better make sure not to be deficient in any nutrient, the results of a 2009 study by scientists from the University of Toronto (Szeto. 2009), suggests doubling your already high-dose multivitamin "just to make sure", is probably the worst "prophylactic" measure you could resort to. After all the pubs that were born to rats who received the high dose (10x RDA) vitamin supplement in the Szeto study, were profoundly insulin resistance, hyperphagic and obese.

While some of these negative consequences of maternal and subsequent fetal mal-nutrishment are either reversible (by replenishing respective nutrients) or induced by developmental changes and consequent malfunction of organs or organ systems, it becomes increasingly clear that some of the changes are of epigenetic nature, which means that certain DNA strains are activated or deactivated via methylation in response to dietary restrictions or, as in the case of overall malnurishment or the so-called "high fat diet", an under-, respectively overabundance of energy.

Protein (mal-)nutrition during pregnancy and epigenetic consequences

Image 3: The effects of protein malnutrition on pediatric health are profound, at any age!

Of the macronutrients, dietary protein appears to exert the most profound epigenetic effects during the fetal period. The offspring of protein malnurished rats in a 2005 study from the University of Southhampton in the UK (Lillycrop. 2005), for example, had ~20% lower PPAR-alpha and glucocorticoid receptor methylation status than that of rats on a protein sufficient diet. The subsequent >10x higher PPAR-gamma and 2x higher glucocorticoid receptor mRNA expression render provide a "mechanistical" (obviously it is a physiological one, but if we think of the body as a epigenetically controlled machine, the expression "mechanistic" would be adequate) explanation for the increased susceptibility to dietary induced obesity in later life - an effect, by the way, which has only recently been shown to be sex-depended and more pronounced in female than male offspring of mice (van Straten. 2012).

A high protein content of an overall energy deficient diet, on the other hand, has recently been shown to correct the increased cardiovascular disease risk subsequent to fetal malnutrition in mouse offspring (Kavamura. 2012), which could in fact be related to a correction, or rather aversion of the detoriations in glucocorticoid receptor expression observed in the Lillycrop study (see above).

Note: A 2011 study from the Department of Nutritional Sciences at the University of Toronto suggests that even though soy may be less of a problem for women than men, you would be ill-advised to eat (or feed your pregnant wife) larger amounts of soy protein. After all, the scientists comparison of soy vs. casein based diets showed that the offspring of the soy-fed rodents exhibited increased body and fat pad weights and a statistically highly significant increase in systolic blood pressure - an effect that was, in this case, more pronounced in the male, than in the female pubs (Jahan-Milan. 2011).

Interestingly, we see very different effects with postnatal protein restrictions, only recently, a group of researchers from the Universidade do Estado do Rio de Janeiro, in Rio de Janeiro, Brazil (Lisboa. 2012), that the offspring of the dams received a low protein (8% vs. 23%) diet during the lactation period had lower adipocytes area, a higher leptin:visceral fat ratio, increased leptin receptor expression (and thusly sensitivity) and significantly higher levels of thyroid hormones (T3 and T4) at lower TSH levels than the adult offspring of mothers who had received the normal diet during lactation. These results emphasize the need for further research and confirm my repeatedly voiced concern about jumping to radical conclusions. After all, the same high protein diet that could decrease the CVD risk of your children could be one of a myriad of factors which contribute to the rampant rise of thyroid problems, these days.

Don't surrender, and outdo your well-meaning parents

If coupled with prenatal stress exposure, which has also been shown to induce profound negative effects on the glucocorticoid metabolism of the offspring (Brunton. 2010), protein malnutrition could form a "duo infernale", which would verify the initial statement that some people have an "epigenetic disadvantage" compared to others. It would yet be unfair and above all unproductive to lay the blame on your parents. After all, familial studies suggest that only 30%-50% of the weight gain could potentially be explained by (epi-)genetic factors (Lawin. 2009). This leaves a huge margin for you to intervene and still emphasizes the importance of watching your own diet - for your own, and the sake of your children and grandchildren (I guess, we forget about humanity for now ;-)