After years of throwing terms around like "overweight", "obese", and
"morbidly obese", doctors are conceding that the BMI where they derived
those terms might actually be wrong. The BMI (Body Mass Index) has been
around for almost 100 years, but since 1998, the BMI has been the gold
standard that doctors and the government use to determine whether or not
a person was fat. To calculate BMI, you divide your weight by the
square of your height. For those of us who are not math majors, several
websites and charts hanging in our doctors' offices are happy to tell us
if we are overweight or obese. For instance, my sister who is 5'9" and a
nice, trim, compact 170 pounds is considered overweight.
But new
research put out by the Mayo Clinic indicates that the BMI might not be
the best indicator for obesity after all. An athletic, muscular man who
is 5'10" and 200 pounds comes up "overweight" on the BMI scale because
of his muscle mass. Muscle weighs more than fat, so simply using height
and weight is not an accurate measure of a person's fitness. BMIs that
indicate a person is overweight (25-29) or obese (29 and up) can affect a
person's health and life insurance status erroneously.
For
years, it has been assumed that those indicated as "overweight"
according to the BMI were at a much higher risk of dying from heart
related conditions. But the new research that the Mayo Clinic in
Rochester, Minnesota, published indicates something quite different. In
their study of 250,000 people with heart disease, those with a BMI that
indicated overweight status had less chance of dying from heart problems
than those with a normal BMI. And people with a normal BMI were less
likely to die than people with low BMI. And as expected, severely obese
people did have a higher incidence of death from heart-related disease.
The difference in the overweight group is likely to be muscle. People
with more muscle are more fit and healthy, but that muscle puts them in
the overweight group for their height. Numbers that get tossed around
frequently are that 60% of Americans are overweight and half of those
are obese. These numbers are based strictly off the BMI, and the group
of overweight Americans is likely to be much lower.
But before
we all breathe a sigh of relief and down a cheeseburger, bag of potato
chips, and a carton of moose tracks ice cream (yum), the study leader
did say that the research did not prove that obesity was harmless. Being
overweight or obese still carries an increased risk of heart disease, diabetes and certain types of cancers.
So how do we measure the risks? According to experts in the heart health field, the risk of heart disease
can be calculated by measuring your waistline. Or even better, by a
hip/waistline ratio. (I know, those were two things I never wanted to
measure again either). That is because the fat in your abdomen is
dangerous fat. Fat packed around the organs in the abdomen is more
metabolically active, which means it releases more of the acids that
increase heart disease risk and other conditions like high blood
pressure and high blood sugar.
To calculate the waist-to-hip
ratio (to keep an acronym it's called the WTHR), measure both your waist
and hips, and divide the waist size by the hip size. And yes, this
indicator realizes the difference between men and women, unlike the BMI.
For women, the ratio should be no more than 0.8. In other words, your
waist should be smaller than your hips. And for men, it should be 1.0 or
less. That means that a man's waist should be the same measurement as
his hips or smaller. The beer-and-pizza belly has to go!
And
that's where I realize that I need to exercise a bit more and eat better
foods. I always coast along at my nice BMI of about 22. But the new
WTHR indicator doesn't look so nice. And there is one formula that never
fails: eat less than you use. That will take care of BMI, WTHR and any
new fat indicators just showing up.
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