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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.
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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.
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 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.
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Dated 5 January 2011
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