Science is hard. Real science requires time, patience, modesty, and a high tolerance for failure. Good ideas can lead to better ideas, or to dead ends, and these dead ends actually help us map out our reality. Quite a while back, I wrote about a study of certain compounds in chocolate and their effect on the cardiovascular system. One of the things I liked most about the study was the authors' refusal to draw overly broad, immodest conclusions from their findings. That's how real scientists operate.
This is in stark contrast to undereducated pseudo-scientists---if they see a result congruent with their beliefs, it's cannon. There's no situation or population that can't benefit from their "discovery". Once again, the Huffington Post's Patricia Fitzgerald gives us a nice example of the phenomenon. She lists seven reasons not to feel "guilty" about enjoying chocolate. This beats my one reason---it's not good to feel guilty about the food you consume.
Each of her reasons is based on scant evidence taken to outrageous extremes. Her first claim is that chocolate is high in "anti-oxidants" and from there she concludes that it's good for you.
Her second claim is that it "helps with cholesterol" and to support this claim she links to a press release of a small pilot study of LDL oxidative characteristics. There is no clinical relevance to this study (which doesn't rule out future clinical relevance, of course).
Her third claim is that it reduces "inflammation", and once again she links to a press release of CRP measurements. As we've previously discussed, "inflammation" is not magic, and real scientists will incorporate this interesting finding into future research.
She also cites a study of chocolate and hypertension, and mood, etc, etc.
Look. Very few substances are so bad for you that they should be avoided completely. Conversely, very few substances are so good for you that they should be consumed like medicine (with the exception of...er...medicine). To find a clinical benefit to something, it has to be tested for plausibility, safety, and efficacy. You can't just say that because 23 people derived some sort of benefit that you should go buy now now now. A real study, with clear, relevant endpoints, controlled for confounding variables needs to be done to draw these kinds of conclusions. Numbers matter. What if it turns out that chocolate actually raises HbA1C? What if it turns out that even though it lowers CRP it increases mortality? What if it decreases blood pressure but with a number needed to treat (NNT) of 20,000?
Science is hard. Fitzgerald is not only unqualified to practice science; she's unqualified to even talk about it.
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In Nick Lane's latest book a similar idea is pointed out. Namely, that your cells are trying to tell you something when the level of free radicals are raised. It might be harmful to over load anti-oxidants. Somewhat similar to the notion that if you have gastric reflux you shouldn't over load your system with too much base. (Tums, baking soda) Over time it is possible to simply over produce acid to overcome the over adminstration of a solution to the acid. Sorry, if that is convoluted, I don't get much of a chance to have conversations about what I read, it makes retention and vocabulary problematic. I can understand the point and the process, but might forget or misrecall the specific molecule or word. Good article though. I enjoyed it a great deal and think you've got a very valid point.
What if it only works when it's filled with creamy nougat?
As far as I know, here's where we stand on anti-oxidants:
1. In vitro, they have been shown to scavenge free radicals.
2. In vivo, when injected into cells in sufficient concentrations they have been shown to scavenge free radicals.
3. There is no way to get sufficient cellular concentrations through dietary means.
Reason #7 is really the only one that matters. Quality of life is pretty important and no chocolate would definitely worsen mine.
There was an interesting article in PLoS recently about a group of hunter-gatherers living in the Bolivian Amazon with a mean life expectancy at birth of 43 years.
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0006…
"Public health infrastructure and medical services remain minimal for most Tsimane and they continue to incur high rates of infection. Immunization was only regularly administered in the past decade and is still sporadic in many areas. Medical surveys show that about one-third suffer from respiratory illness, one-fourth from gastrointestinal illness, and over three-fourths from intestinal helminths or pathogenic protozoa. Anemia is highly prevalent and physical growth is stunted. Their history of infection and chronic low-grade inflammation lead us to predict greater PAD and hypertension.â
They found no PAD at all, even with very high levels of CRP.
There is no clinical data showing that dietary consumption of antioxidants protects against PAD (or anything else). All of the large, long duration, double-blind, placebo controlled studies have shown either no effect or a slight negative effect of supplemental antioxidants (negative as in health gets worse).
The only data supporting the idea that antioxidants are good for you are either short term, or are from a self-selected diet. My hypothesis that the composition of a self-selected diet is regulated by physiology to optimize antioxidant consumption to whatever oxidative stress setpoint physiology is trying to achieve. Diet composition is an effect of oxidative stress, not a cause.
Free radicals are critically important signaling molecules. The body has unlimited capacity to make superoxide. If there are too many antioxidants in the diet (i.e. more than what ever the bodyâs oxidative stress setpoint calls for) the body then has to destroy them by making more superoxide (at some metabolic cost, and likely with additional damage).
chocolate contains modest amounts of antixidants, at best, and no in-vivo effect in humans has been demonstrated (to my knowledge). more important, the entire idea that one can get a benefit by increasing antioxidant intake is questionable. Just because it might work in carefully controlled animal studies doesn't mean it translates to humans.
In a large cohort study of >75k people, multivitamins, vit C and E had no effect on cancer mortality. Vitamin E use was associated with a marginal decrease in CVD mortality, but this may be a multiple endpoint issue. Pocobelli Am J Epidemiol. 2009 v170(4):472. An earlier cohort study was also negative: Muntwyler Arch Intern Med. 2002 v162(13):1472. A prospective randomized trial of >8000 found no benefit: Lin, JNCI 2009 v101(1):14. A systematic Cochrane review in 2008 found no evidence to support benefit.
There's only 1 reason to eat chocolate: pleasure.
Didn't SGU have a "Science or Fiction" bit about free radicals playing a role in satiety? Or was that the fiction...?
What if it turns out that chocolate actually raises HbA1C?
Try the unsweetened.
Huh, she didn't mention the one reason I always see chocolate praised for. It's a good source of copper, and our rate of consumption in the US is generally considered the reason you rarely see copper deficency.
I am a recovering chocolate addict, abstinent for over a year after breaking a 1000-2000 calorie a day chocolate habit. Recently, I've tried adding 1/4 teaspoon of unsweetened cocoa to my morning oatmeal to benefit from the antioxidants and maybe raise my HDL. Not only do I find that I am not addicted to the bitter cocoa, but I can hardly stand it without the sugar and fat that is normally added to chocolate. My conclusion is that chocolate is a baffling food - horrible on its own, but irresistable when combined with sugar and fat. You won't find me eating cocoa powder, or even chocolate soda (sugar and cocoa), but then again my motto has always been, why eat cake or ice cream if it's not chocolate?
Chocolate to me is like watching tv and surfing the Internet at the same time. You get two fixes, not just one, and it's pure heaven.