Low-carb dieters are getting more good news from two studies out Monday.
The largest studies to date, conducted by the Veterans Affairs Medical Center in Philadelphia and Duke University, confirm that people on carb-counting plans lose more weight in the short-term than do traditional dieters.
They also found that low-carb dieters see more improvements in triglyceride levels, blood fats linked to coronary disease. This is important because nutritionists have raised concern for years over the diets' high intake of saturated (animal) fat and its potential impact on the heart.
On the downside for the millions of low-carb dieters: They don't seem to lose any more weight over the long-term than traditional dieters.
Researchers at the VA hospital followed 132 obese adults for a year. Half of the group ate less than 30 grams of carbs a day. The other half tried a more conventional plan, cutting 500 calories a day and limiting fat to about 30 percent of calories.
Findings in Tuesday's Annals of Internal Medicine:
At six months the low-carb group had lost an average of 13 pounds; the conventional dieters lost about 4 pounds.
After a year, the low-carb group was down an average of 11 pounds. The other group continued to lose and dropped an average of 8 pounds. The difference was not statistically significant.
The low-carb group had a decrease in triglycerides, and the diabetics had better control of their blood sugar.
Both diet groups had fairly high dropout rates, losing almost a third of the dieters.
"The take home message: For a year, it appears that a low-carbohydrate diet is safe," says internist Linda Stern, the study's lead author.
The Duke study, also in the medical journal, tracked 120 overweight people for six months. Low-carb dieters lost 26 pounds compared with 14 pounds for traditional dieters.
The low-carb dieters had better improvements in triglycerides and good cholesterol than the traditional dieters.