A large scale 250,000-participant study has found that the Body
Mass Index (BMI) which has been used for over 5 decades to gauge
risks of heart disease is actually an inaccurate measure. The BMI
takes into account total weight and in unable to differentiate
between fat and muscle mass so that several people who have a
greater BMI are actually healthier than others, though theory
suggests otherwise.
This index, invented by Belgian statistician and sociologist
Adolphe Quetelet is calculated by dividing weight in kilograms by
the square of height in meters. Generally, the normal healthy range
is between 18.5 to 24.9, with a person whose BMI is lower being
considered underweight. A BM Index between 25 to 29.9 falls into
the overweight category, while above this would be considered
clinically obese.
This study conducted by a group from Mayo clinic found that though
as expected, the obese participants had greater risks of
cardio-vascular disease, this was not always true for the
overweight group. Many participants from the overweight category
were healthier than those who fell in the 'normal' range. This was
because BMI did not always necessarily have a connection with fat.
A large muscle mass could also account for a greater Body Mass
Index. For instance, New Zealand's large rugby star, Jonah Lomu,
has a BMI of 32, however it would be inaccurate to classify him as
'obese'.
Note however, that the researchers do not completely disregard this
index, nor do they suggest that being overweight is harmless.
Rather, they call for a different measure, which will be able to
distinguish between weight contributed by fat and that contributed
by muscle.
A more reliable method and a much simpler one, suggest the
researchers, involves only a regular measure tape. This method
involves calculating the waist-hip ratio, whereby abdominal fat is
accounted for. This pot-belly indicator is seen to be much more
accurate in gauging fat mass and connecting it to cardio vascular
risks.
However, Dr. Robert H. Eckel, of the University of Colorado and
previous president of the American Heart Association cautions
against disregarding the BMI completely. He points out that this
index has been more accurate than inaccurate in the past and much
more research needs to be done before it can be completely ruled
out.
Source: http://www.earthtimes.org/articles/show/8207.html
hey looks like BMI not really that good in telling us whether we're
really unhealthy!!
