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Re-activateThere are passionate advocates on both sides, and plenty of people who'll warn you of the dangers of one or the other. Then there are some who say neither work, and you'll only put the weight back on again anyway.
Well, there's finally a good-quality study comparing the two diets over a two-year period, which also looks at measures like cholesterol and other biochemical markers. And the results are in.For weight loss it's a dead heat. People following either the low-carb or low-fat diet had lost on average 7 percent of their body weight by the end of the study—an overall weight loss of around 15 and a half pounds.
People in the study had a BMI (body mass index) of 30 to 40 at the start of the study, putting them in the category of obesity. We know that losing 5 percent or more of your body weight can have significant health benefits for people who are obese. So the diets clearly worked.The diets were only part of the story, though. Both groups of people also followed an intensive lifestyle training program, to help them break unhealthy habits. Other studies have shown this can help a lot when trying to stick to a weight-loss diet.
And the naysayers aren't completely wrong. On average, people lost more weight in the first year, then put some of it back on in the second year. So maintaining a healthier weight is still a problem.What about the health measures? They were almost identical, with the exception of lipid levels. While "unhealthy" LDL cholesterol went up for the people on the low-carb diet in the first year of the study, by the end of the study it was the same as in the low-fat group. And people in the low-carb group had better levels of "good" HDL cholesterol throughout the study.
It's hard to know exactly how important these changes in lipid levels might be because the study didn't follow up for long-term outcomes such as heart attacks. However, better levels of HDL are usually linked to better heart health.What you need to know. Either a low-carb or a low-fat diet can help you lose enough weight to improve your health, should you need to do so. The key is to find a program that works for you, and stick to it. Support from professionals, or as part of a group, can also help.
—Anna Sayburn, patient editor, BMJ Group
ConsumerReportsHealth.org has partnered with The BMJ Group to monitor the latest medical research and assess the evidence to help you decide which news you should use.
Take a look at 8 secrets of successful dieters and learned more about which diet works best for weight loss.
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