what are the basic evidence in the causes of the obesity epidemic?
We are dealing with a multi-factorial issue, and so good "evidence" is extremely hard to come by. I've done quite a lot of reading on the issue though, and for what it's worth, here's my take on some of the causes of the epidemic:
1. Less exercise.
2. Bigger portions. Studies show that if you give people bigger portions, they consistently eat more, without even realizing that they are doing so.
3. The over-emphasis on eating carbs in the food pyramid. I think it is becoming clear that for many people a high-cabohydrate diet produces hunger and subsequent eating. The glycemic index is likely over-simplistic, but it contains some truth. Ditto for the Atkins diet.
4. The "low-fat" drama. People wrongly assume that low fat = low calorie. There is also some evidence that a diet too low in essential fatty acids (in particular olive oil and fish oil) makes it harder to lose weight. (There is strong evidence that fish oil and olive oil are good for your cardiovascular system.)
5. Inadequate calcium consumption - calcium intake has been steadily dropping. There is interesting new evidence that increasing calcium consumption, in particular via dairy products, causes weight loss (particularly in women).
6. Drug side-effects. Lots of drugs turn out to cause weight-gain for some people when used for long periods. People know about the high-profile weight-gainers, but not about others (for example, many anti-depressants and beta-blockers).
7. The diabetes epidemic. This is a chicken/egg problem, and the direction of causation is quite unclear.
And to justify this post, some minimal discussion of drugs for obesity: <g>
It's not well known, but some approved drugs actually cause weight-loss. For example, J&J's Topamax, which is an anti-epilepsy drug and now also approved as a migraine prophylactic. It's probably not usable as a pure anti-obesity drug because it has too many side effects. Its mode of action is unknown, but at least it's a proof of concept.
Axokine looks pretty promising to me, but of course Miljenko is our local expert there.
SEPR's sibutramine (Meridia) derivatives sounded pretty interesting to me - my guess is that they could have an anti-depressant that causes weight loss. Talk about a blockbuster, but it's clearly on the back burner now, particularly as sibutramine itself is under some attack on safety grounds.
I haven't heard much at all about MLNM's obesity stuff lately.
Peter
P.S. I forgot an obvious one:
8. McDonalds. <g> |
