Visceral Fat: A major health concern in Postmenopausal Women

Following menopause, many women experience a natural increase in
obesity, particularly around their intra-abdominal area, which refers
to fat that stored in and around the internal organs.
Where the body fat is stored in the body is the main determinant of who has metabolic syndrome.

What is Visceral Fat?


Body fat comes in two varieties. There’s
subcutaneous fat, a noticeable layer of fat that lies just below the
skin, and then there’s visceral fat, which is buried beneath the
muscles. Visceral fat is the more worrisome variety because it surrounds
vital organs and is metabolized by the liver, which turns it into blood
cholesterol.



Visceral fat can go largely unnoticed because it’s not visible to the
naked eye. In fact, the only effective way researchers can locate
visceral fat is by magnetic resonance imaging (MRI), which uses magnetic
waves to take a picture of the inside of the abdomen. Researchers can
use this picture to estimate the amount of visceral fat a person is
carrying.


What Causes Visceral Fat?


Your genetic makeup is between 30% and 60%
responsible for the amount of visceral fat you carry. Nevertheless,
research shows that both your diet and your level of physical activity
contribute to your level of visceral fat. People who consume large
amounts of saturated fat and people who perform little or no physical
activity are likely to have high stores of visceral fat.
Short of
talking a physician into performing an MRI on your abdomen, how do you
know how much of this unhealthy fat you have? Check your waistline. A
trim waistline is a good indicator that you don’t have a large buildup
of visceral fat.

Identifying women with visceral fat


The
National Institutes of Health (NIH) have set the following cutoff
points to identify women who are at high risk of developing
obesity-related diseases:
Women with Waist Circumference Greater than 88 centimeters (35 inches)
If
your measurements fall above these cutoff points, there is a good
chance that you are carrying a dangerous amount of visceral fat. Even if
your waist circumference does not exceed the cutoff value, making an
effort to reduce your waistline can still significantly improve your
health.




Getting Rid of Visceral Fat


Research shows that people whose diets contain
polyunsaturated fats in place of saturated fats have less visceral fat.
Polyunsaturated fats are found in high concentrations in sunflower,
corn, and soybean oils, as well as in fish. Also, just exercising
moderately—doing things such as walking, swimming, or playing tennis—on
most days of the week will help you prevent visceral fat from
accumulating. What’s even better is that doing regular bouts of vigorous
exercise can markedly reduce the amount of visceral fat you already
have.


Building muscle—through weight lifting or other resistance
exercises—will help, too. Muscle burns calories and helps you maintain
your metabolic rate. The more muscle you have, the bigger your body’s
engine, and the more likely you will be to burn fat.




Once adipocytes get the signal from hormones and release fat into the
bloodstream, they shrink just like a balloon that you let air out of.
When they shrink, so does your body fat. But if you eat excess fat once
you’ve shrunk your adipocytes, chances are it will find its way right
back to the adipocyte, and once again you’ll gain fat.


No matter how much physical activity you do, adipocytes never
shrink so much that they disappear entirely. Like a balloon that you
let all the air out of, you’re always left with some remnant. The only
way to totally remove adipocytes from your body is with a surgical
procedure such as liposuction or excision. But even with these
procedures, if you go back to eating excess fat, you’ll put all the fat
back on.


The physical activity recommendation for improving health is
to accumulate 30 minutes of moderate-intensity physical activity on
most, if not all, days of the week.

A Recent Study

In
a study (in the Nov. 2004 issue of The Journal of Clinical
Endocrinology & Metabolism,), conducted by Dr. Nicklas and her
colleagues, who examined 58 obese, postmenopausal women, one-half of
whom had metabolic syndrome, to determine whether four factors: aerobic
fitness, body composition, body fat distribution and inflammation,
differed between women with and without metabolic syndrome.

"We found that where the body fat is stored was the main determinant of
who had metabolic syndrome," Dr. Nicklas said. "We were not just looking
at whether the fat was carried on the hips or in the abdomen. We
determined whether abdominal fat was stored between the skin and the
abdominal muscle wall, what we call subcutaneous fat, or stored as
visceral fat, which is beneath the muscles and wrapped around the
internal organs. There have been a number of studies that indicate that
visceral fat is worse because it surrounds vital organs and may lead to
more fat metabolism by the liver."




"There was a dramatic difference in percentage of visceral fat between
those women with metabolic syndrome and the other women in the study,"
Dr. Nicklas said. "Women with metabolic syndrome had 33 percent more
visceral fat, but were similar in all other respects, including the
waist circumference, with almost exactly the same amount of subcutaneous
fat and identical fat cell size."

"The study makes it
clear that all fat is not alike and points to the importance of
improving our understanding of visceral fat," Dr. Nicklas said. "We need
to learn what causes the fat to be stored beneath the muscles or around
the internal organs and determine treatment options to reduce this
visceral fat. More studies are also needed to determine whether
measurement of visceral fat could be used by doctors for more accurate
prediction of cardiovascular disease risk in obese individuals."

While
we need much more research to understand these risk factors, there are
things people can do to reduce their risk," Dr. Nicklas said. "High
intensity exercise seems to preferentially reduce visceral fat and
general weight reduction helps, too"




The bottom line to losing weight and fat is that you must burn more
calories than you consume. If you eat 2,000 calories a day and only burn
1,500, you’re going to gain weight. On the other hand, if you consume
1,500 calories and burn 2,000, you’ll be in caloric deficit by 500
calories. Since it takes 3,500 excess calories to gain a pound, you’d
lose one pound per week if you produced a 500-calorie deficit each day
of the week. To do that, you could reduce your calorie intake by 250 per
day and increase your physical activity by 250 calories per day (for a
150-pound person, a 2.5-mile walk is all it would take). Do that each
and every day of the week and you’ll drop a pound per week.