NEW YORK (Reuters Health) - 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.
The team found no differences in weight loss or fat reductions
between the diets.
"The major predictor for weight loss was 'adherence.' Those
participants who adhered better, lost more weight than those
who did not," Bray told Reuters Health in an email.
But sticking to a diet is tough, Gardner said. Many of the
people who started in Bray's study dropped out, and the diets
of those who completed it were not exactly what had been
assigned.
For example, the researchers hoped to see two diet groups get
25 percent of their calories from protein and the other two
groups get 15 percent of their calories from protein. But all
four groups ended up getting about 20 percent of their calories
from protein after two years.
"They did have difficulties with adherence, so that really
tempers what you can conclude," Gardner told Reuters Health.
Because many people struggle with dieting, Gardner said, they
should select the one that's easiest for them to stick with.
Bray recommended a diet developed by some of his co-authors,
and which is also endorsed by the National Institutes of
Health, called the DASH plan, or Dietary Approaches to Stop
Hypertension.
"We would encourage patients to follow this diet modified as
they and their Health Care Provider chose to emphasize
macronutrient changes that they thought might work best for
them," Bray said.
He added that it will be important for future research to
determine how best to get people to maintain their diets.
"This area of 'weight loss and weight maintenance' seems to me
to be one where fresh insights are most needed," Bray
concluded.
SOURCE: American Journal of Clinical Nutrition, online January
18, 2012.
Continued here:
Study: Calories Count, But Not Where They Come From
