Article: No Just fat But Where It's At

from the Los Angeles Times

Not just fat, but where it's at
Shape may be more important than weight, BMI

Apple-shaped folk at greater risk than the pear-shaped

JANE ALLEN
SPECIAL TO THE TORONTO STAR

Pear-shaped people may have more trouble losing weight from their hips,
thighs and posterior, specifically but it's the apple-shaped folks who
need to redouble their efforts. Their fat is more dangerous.

Researchers have known that carrying extra pounds around the belly and
upper body increases the risk of hypertension, heart disease, stroke,
diabetes and cancers of the breast, ovary and prostate. Now they're
learning why.

The two deposits of belly fat, the subcutaneous layer and a deeper
layer, both function like mini-organs, with blood vessels, connective
tissue, immune cells recruited from bone marrow and the ability to
store and secrete hormones. The inflammatory hormones, enzymes and
fatty acids released by this fat increase the risk of diabetes,
hypertension and high triglycerides.

"We've probably discovered 10 hormones in the past decade that fat can
make," said Susan Fried, a professor of medicine at the University of
Maryland School of Medicine in Baltimore. Two were discovered in just
the last year.

"A new one is being discovered every two to three months," she added.

First, scientists found that fat made leptin, a hormone that regulates
appetite, inflammation and reproduction. They subsequently found that
it makes the inflammatory hormone interleukin-6, which tells the liver
to release more triglycerides and takes the brakes off glucose
production.

Fat makes at least one hormone that's beneficial, the anti-inflammatory
hormone adiponectin, which protects against atherosclerosis and helps
muscles burn fat efficiently. However, too much fat slows production of
this hormone. Low levels have been linked to heart disease in adults,
and new research presented recently at an American Heart Association
conference found that adiponectin levels are significantly lower in
overweight children and young adults, which probably sets them up early
for heart disease.

Such complex biochemical activity belies the fact that fat has its
place, biologically speaking ‹ it's been key to human survival for
about 50,000 years. Being able to store fat in the belly was a hedge
against starvation, while immune cells in the fat protected against
infection. But most people in modern cultures suffer from the
consequences of dietary excess.


Over the long term, such excess becomes much more than a superficial
problem.

The subcutaneous fat layer, which lies just beneath the skin and can be
easily pinched, is damaging enough, but it's only the beginning. Excess
inches at the waist often suggest the presence of visceral fat. That
deeper layer includes the omentum, a sheet of fat that hangs from the
bottom edge of the stomach over the intestines.

Visceral fat contains more metabolically active fat cells than those
that accumulate between the skin and muscles of the abdomen or the
hips, thighs and buttocks. It's particularly unhealthy because it
releases more inflammatory hormones and fatty acids than other fat.
Worse still, it sends them right through the portal vein into the
liver, where they adversely affect glucose metabolism, blood pressure
regulation and production of unhealthy blood fats called triglycerides.

The enhanced understanding of fat has led some experts to say that a
person's shape can be a more meaningful indicator of obesity and
disease risk than the often-touted body mass index. BMI, an expression
of the relationship of weight to height, does not distinguish between
fat and muscle, so it can be particularly misleading for people who
tend to accumulate fat in the upper body, including those of Asian
ancestry, Hispanics and adults over 50, according to Dr. David Heber,
director of the University of California, Los Angeles Center for Human
Nutrition.

"Weight-to-height ratio doesn't tell the whole story," Heber said. BMI
has helped track the epidemic of obesity,a worsening problem in North
America,but for individuals, "shape is more important than weight."

Whether people who gain weight tend to be pear-shaped or apple-shaped
depends on many factors, including genetics, how much they exercise,
and hormones. Women have a higher percentage of body fat than men,
mostly because their bodies make the reproductive hormones estrogen and
progesterone. Those hormones cause them to lay down fat in the lower
body, where it resists weight loss.

The good news, nutrition and obesity experts say, is that once you lose
the excess fat, you can improve your health and lower your disease
risks. Diet and exercise actually shrink the deep visceral abdominal
fat faster than the shallower, unsightly blubber that's the bane of
overweight people.

Canadian researchers reported in last month's issue of Medicine &
Science In Sports &Exercise that even modest increases in physical
activity can improve men's cardiovascular fitness and reduce abdominal
fat, regardless of BMI.

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Diva
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There is no substitute for the right food