Is the Can Worse Than the Soda?

DevotedSkeptic sends this excerpt about research that found a correlation between the use of a common food-packaging chemical and obesity rates. "Since the 1960s, manufacturers have widely used the chemical bisphenol-A (BPA) in plastics and food packaging. Only recently, though, have scientists begun thoroughly looking into how the compound might affect human health—and what they've found has been a cause for concern. Starting in 2006, a series of studies, mostly in mice, indicated that the chemical might act as an endocrine disruptor (by mimicking the hormone estrogen), cause problems during development and potentially affect the reproductive system, reducing fertility. After a 2010 Food and Drug Administration report warned that the compound could pose an especially hazardous risk for fetuses, infants and young children, BPA-free water bottles and food containers started flying off the shelves. In July, the FDA banned the use of BPA in baby bottles and sippy cups, but the chemical is still present in aluminum cans, containers of baby formula and other packaging materials. Now comes another piece of data on a potential risk from BPA but in an area of health in which it has largely been overlooked: obesity. A study by researchers from New York University, published today in the Journal of the American Medical Association, looked at a sample of nearly 3,000 children and teens across the country and found a 'significant' link between the amount of BPA in their urine and the prevalence of obesity."

Comments

Re:Silly

[timeOday]

And in general, I think while environmental factors do probably contribute in a small way to obesity, it seems silly to worry about these things when the real causes are pretty damn obvious: eating wrong and getting no exercise.

Oh boy, thanks for sharing your tremendously valuable Common Sense with us.

In fact this study is shocking and here is why (in bold):

The researchers pulled data from the 2003 to 2008 National Health and Nutrition Examination Surveys, and after controlling for differences in ethnicity, age, caregiver education, income level, sex, caloric intake, television viewing habits and other factors, they found that children and adolescents with the highest levels of BPA in their urine had a 2.6 times greater chance of being obese than those with the lowest levels. Overall, 22.3 percent of those in the quartile with the highest levels of BPA were obese, compared with just 10.3 percent of those in the quartile with the lowest levels of BPA.

So here is what I pull from the emphasized bits:

• No, it is not explained by caloric intake. Nor by physical activity (or at least a proxy for it).
• The effect size is enormous. A 160% increase in risk of obesity!
• The sample size is large: 10.3% and 22.3% are both relatively large proportions of subjects in the study. So this is almost certainly not a spurious correlation between rare events.

The idea of significantly impacting the obesity epidemic simply by replacing BPA with something else is hard to believe. But occasionally a technical breakthrough on what was previously considered an issue of character and morality does does occur, and can be revolutionary: consider birth control.

WARNING: BPA lining in CANNED FOOD as well !!

[Taco Cowboy]

One thing about this article submit is that it only tells part of the story.

BPA lining is not only present in the soda can.

BPA lining is also present in CANNED FOOD - yes, inside the cans that are used for CANNED FOOD

http://www.thedailygreen.com/going-green/tips/bpa-in-canned-foods

Re:Silly

[TechyImmigrant]

Indeed. But it goes further. There is substantial evidence that bulk fructose, in it's role as 50% of sucrose is the underlying cause of the modern rise of obesity.

The story goes like this..

The POMC neurons in the brain (the VMH - Ventromedial Hypothalamus to be precise) regulates energy expenditure are hunger based on levels of glucose, non esterified fatty acids and various hormones, principally insulin and leptin.

Bulk fructose damages those cells, so the regulation goes out of whack. Then the carb-insulin mechanism of obesity kicks in and you're sensitive to carbs. Now regardless of the leptin signaling and the copious NEFAs, the brain isn't telling the rest of the body that you're in an energy rich environment and so it resist burning fat in favor of storing it and you're hungry all the time.

The evidence is pretty good and getting stronger as new studies dig in. E.G. There are many ways to break the VMH in rats. Do it and they get fat. Starve them and they stay fat, but rob their own muscles and organs in order to survive, while leaving the fat cells intact. MSG will do it, Fructose will do it. An ice pick will do it. Section the brains of freshly dead fat people and they have exactly the same lesions in their VMH.

We never had bulk fructose until recent centuries and we never had it in the quantities we have it now. People fart around arguing about micro-nutrients and trace elements looking for reasons, but the macro-nutrients are where the first order effects can be explained.