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Obesity Grows Despite Diets to Curb It
Americans are getting morbidly fatter even as they speed up their
efforts to lose weight.
The American Heart Association hosted a panel Friday to try to
unearth what Americans eat and what, exactly, is contributing to
the rising tide of obesity.
Spurred
by the aggressive marketing of diets that promote fat over carbohydrates,
researchers at the Mayo Clinic decided to see if these campaigns
were affecting what people were eating. After surveying 1,200 residents
of Olmstead County, Minn., the answer was a resounding yes. Between
1999 and 2003, a larger proportion of calories were coming from
fat, saturated fat, and dietary cholesterol.
"The findings reverse some of the trends seen over the past
20 years," says lead author Dr. Randal J. Thomas. Thomas adds
that these findings "suggest that there are some tough times
ahead with respect to heart disease."
While the popularity of low-carb, high-fat diets may indeed be
behind some of these changes, Thomas says many other factors could
also be contributing.
Another study found a number of characteristics that seemed to
be related to consuming larger portion sizes among a group of postmenopausal
women with type 2 diabetes who were trying to follow the Mediterranean
diet. This group has a high risk of developing coronary heart disease.
Women with higher incomes, education levels, and body weight and
a lower age (within the range, which began at 45) tended to eat
larger sizes. Also, larger portion sizes were linked to lower levels
of physical activity, higher "bad" cholesterol, less ability
to manage stress, greater depression, and higher blood pressure.
Researcher Kristie J. Lancaster of New York University found important
differences between ethnic subgroups of African-Americans who are
usually lumped together in terms of risk. Non-Hispanic blacks who
were born in the United States had a higher 10-year risk of developing
coronary heart disease (CHD) than those born outside the United
States. Those born in the United States also had a higher proportion
of calories from fat and saturated fat and ate fewer fruits, vegetables
and legumes. They were also more likely to smoke.
"All black groups need to improve in diet and CHD risk,"
Lancaster says, "but, in particular, African-Americans have
greater needs when it comes to diet and CHD risk, so we need more
investigation of these groups."
A national survey of 6,739 adults found that about half felt that
"dinner was not right without meat." Meat, of course,
tends to have more fat, and people who consume more meat tend to
be heavier. Less than a third of the respondents (29 percent) felt
they ate enough fruit and vegetables according to the government's
recommended guidelines.
"This information could be used in the development of nutritional
information for healthy eating," says Alison Jane Rigby of
Stanford University.
Finally, another study looked at 4,000 participants in four countries
-- China, Japan, the United Kingdom and the United States -- to
find associations between weight and dietary intake.
"We
looked at people who were winning the game of weight control,"
says Linda Van Horn of Northwestern University. "Lo and behold,
what we did find is that, without exception, a high complex-carbohydrate,
high-fiber, high-vegetable diet was associated with a low body mass
index."
High protein, especially high animal protein, diets were associated
with a greater body mass index. "The association between dietary
patterns that are associated with lower body weight are consistent
with those the American Heart Association has recommended for years,"
Van Horn says.
The overall weight loss message, as AHA spokesman Dr. Robert H.
Eckel put it, is "very, very simple but difficult to implement."
That message is: take in less than you give out. "It has to
be a matter of energy balance," Van Horn says. "[In our
study], the healthiest people were eating the most calories but
had the leanest body mass index, but the point is to be physically
active. That allows you the discretion to have additional calories.
You can get away with more calories as long as you're burning them
off."
One way to do that, Thomas says, is to "turn off the TV and
eat at home. Doing simple things like that can help you be more
active."
And Americans need to get away from this bipolar debate on carbohydrates
vs. protein, Eckel says. "When we're talking about weight,
it's no longer fat or carbohydrate or protein. It's pure calories,"
he says. "We need to turn the public's attention to calories
again."
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