Reuters AlertNet - Study shows no one knows which diets work best
Wow, a new standard for most misleading news coverage and title. The study was of the commercial dietary companies, it wasn't a study of medical/dietician diets. They found, shockingly (not), that the commercial diet companies had no real evidence to back their claims of exceptional efficacy. Weight Watchers did better than the commercial competition.
Reuters isn't the only ridiculous headline, Google News had many examples.
Update 1/12/05: I finally read the original JAMA article. Wow, the media coverage was even worse than I thought.
This was really an ambitious study. They looked at the Atkins (low carb) vs. Zone vs. Ornish (low fat) vs. standard (Weight Watchers) diets. They actively intervened for two months then followed up a year later. Subjects didn't get to pick their diet of choice -- they were randomly assigned.
The result was they all the dieters did dismally. In fact, they did worse than the dismal results one usually gets from diet studies. We don't know why -- was it something about how they were recruited? Was it related to all those lost to follow-up? Was it because people do better when they get to pick their own diets?
The main conclusion was the low card (Atkins) diets don't work any better than any other diet. Low carb seems to work a bit better at the 2 month mark (perhaps, as my friend Jim Horn noted, because it's so much work to prepare the food people eat less) but then people stop complying.
There's an increasing suspicion that obesity, once established, is not a treatable condition. Yeah, in theory it's reversible, and sure some lose weight for years (almost always due to serious exercise increases with some moderate food limitation), but we actually have better treatments for most of the leukemic disorders than we have for obesity.
We know obesity can be prevented. Among wealthy societies there are some settings with more obesity, some with less. Activity is the key variable. We also know than in an infotech centric, sit down, fly around society in which most persons can easily afford vast amounts of food, that we are heading for a plague of obesity that may break our healthcare budget.
We need serious new drugs, and the drug companies are investing billions (trillions) looking for this grail. (Billions for antiobesity drugs, a trifle for new antibiotics -- it's a bad story.) At least half of humanity will take these drugs for their entire lives -- or until we genetically modify humans so we eat less.
PS. Is the situation really so hopeless? Yes. In theory we could do many things to encourage and facilitate physical activity in all domains of our society. Sure. In practice this is the social equivalent of an individual actually sticking with a diet. Theoretically possible, but practically implausible -- especially in the current political climate where riding a bicycle is a sign of communist/terrorist sympathies.