NEW YORK  - Sticking to diets with strict proportions of fat, carbs and protein may not be more effective for people who want to lose weight and fat mass than simply cutting back on calories, according to a new comparison of four diets. The results suggest that it doesn’t matter where the calories come from, as long as dieters reduce them.

“If you’re happier doing it low fat, or happier doing it low carb, this paper says it’s OK to do it either way. They were equally successful,” said Christopher Gardner, a Stanford University professor who was not involved in the study. Dr. George Bray, who worked on the new study, said earlier research had found certain diets — in particular, those with very little carbohydrate — work better than others. Diet books also often guide consumers to adopt a particular type of meal plan, such as low-fat or low-carb-high-protein diets. But there hasn’t been a consensus among scientists.

So Bray, of Pennington Biomedical Research Center in Baton Rouge, Louisiana, and his colleagues randomly assigned several hundred overweight or obese people to one of four diets: average protein, low fat and higher carbs; high protein, low fat, and higher carbs; average protein, high fat and lower carbs; or high protein, high fat and lower carbs.

Each of the diets was designed to eliminate 750 calories a day from the people’s energy needs.­

After six months and again at two years after the diets started, the researchers checked in on people’s weight, fat mass and lean mass.

At six months, people had lost more than nine pounds of fat and close to five pounds of lean mass, but some of this was regained by the two-year mark.

People were able to maintain a weight loss of more than eight pounds after two years. Included in that was a nearly three-pound loss of abdominal fat, a reduction of more than seven percent.