If you read the paper in the mornings, you may already have seen the news — the latest issue of the New England Journal of Medicine includes a study showing that all diets work the same, it’s only calorie intake that matters.
Some previous studies have found that low carbohydrate diets like Atkins work better than a traditional low-fat diet. But the new research found that the key to losing weight boiled down to a basic rule – calories in, calories out.
“The hidden secret is it doesn’t matter if you focus on low-fat or low-carb,” said Dr. Elizabeth Nabel, director of the National Heart, Lung and Blood Institute, which funded the research.
Limiting the calories you consume and burning off more calories with exercise is key, she said.
In between quotes like this and “success stories” from two program participants, this particular article does get around to mentioning that all participants started regaining weight after a year. Some articles don’t. The version I saw in the commuter paper coughed and whispered it at the end, but headlined with “All diets the same!” and touted the supremacy of calorie counting. Most people who read coverage of this study could be forgiven for coming away thinking that no matter how many carbs you eat, what really matters is staying below a set number of calories — just another version of “well, FAD diets don’t work, but I’m just on a regular calorie-counting diet so it’ll work for me.” Because for the most part, that’s what the articles say.
Well, I read the study. And here’s the rest of the story:
- The study only followed people for two years, not five, but already saw weight regain in almost all participants. Nor were they surprised. The researchers said that they chose a two-year period because “weight loss typically is greatest 6 to 12 months after initiation of the diet, with steady regain of weight subsequently.”
- About half the participants who completed the study ended up weighing more than baseline at the two-year mark.
- Participants in every group were on average eating FEWER calories at the two-year mark, when they were regaining, than they were at the six-month mark, when they were still losing weight. (ETA: Almost every group. Kate double-checked me and one group was eating about 22 calories more on average at two years than at six months.) (ETA: No, I was right the first time.)
- One of the researchers reports the following conflicts of interest: “Dr. Greenway reports receiving consulting fees from or serving on a paid advisory board for Anian, Bristol-Myers Squibb, Clarus Health, Encore Pharmaceutical, Leptos Biomedical, MDRNA, Novo Nordisk, General Nutrition Corporation, Catalyst, Jenny Craig, Orexigen, Lithera, and Basic Research, receiving lecture fees from BAROnova, Lazard, and Biologene, and owning equity in Lithera.”
- ETA: From MissPrism: “They also wouldn’t let ‘insufficiently motivated’ people on the study to begin with, and haven’t published the questionnaire or criteria that they used to determine level of motivation.” Depending on the definition of “motivated,” this could easily disqualify anyone who practices HAES.
The Globe and Mail coverage reported this as “all diets work.” It looks to me more like “no diets work.” And hey, that’s how it was reported last time someone did this study, less than two years ago, when researchers analyzed the results of 46 different weight-loss studies and found that there wasn’t much difference between various diets because they all sucked. It’s interesting how “there’s no material difference between diets” is now being reported now as “all diets work as long as you cut calories,” even though the primary desired effect of diets — weight loss — isn’t being observed on even fairly short time scales. How, pray tell, does that mean diets “work”? A broken Ford and a broken Honda both “work the same” too, but since neither of them does what they’re designed for, we call them both lemons.
Now granted, they did find that the participants’ diet and exercise changes resulted in lower triglycerides, higher HDL, better metabolic function, etc. And what else besides diets could possibly have this effect? Gosh, I thought you’d never ask.