Growth Hormone May Be Fat Fighter
Low Doses of Growth Hormone May Trigger Weight Loss
Feb. 13, 2004 -- It may sound contradictory, but a dose of
growth hormone could be just what obese people need to help them shed pounds
and become smaller.
A new study shows that obese people have lower-than-normal
levels of growth hormone in their body, which may make it harder for them to
Researchers found that low doses of growth hormone helped men
and women lose fat while keeping muscle. It also helped them keep it off for up
to nine months.
Growth Hormone Prompts Weight Loss
Researchers say the goal of weight loss is to lose the fat but
keep the muscle, but so far no drugs have been able to help people achieve that
The study, published in the current issue of The Journal of
Clinical Endocrinology and Metabolism, looked at the effects of giving
obese people low doses of growth hormone in an attempt to help them selectively
lose fat while retaining lean muscle tissue.
Researchers say previous studies on growth hormone and weight
loss have used relatively high doses, which resulted in unwanted side effects,
such as swelling, hypertension, joint pains, and glucose intolerance (a risk
factor for diabetes).
The study consisted of 59 obese men and women, whose average
BMI was 37 (BMI is a measure of weight for height). The participants gave
themselves nighttime injections containing 200 µg of growth hormone or a
placebo for one month. For the next five months, the dosage of growth hormone
was increased to 400 µg per day in men and 600 µg in women. Researchers say the
increase was necessary because prior studies show resistance to the drug can
develop over time, especially among women. Both groups were prescribed a diet
and were instructed on lifestyle modification and exercise.
Among the 39 people who completed the 6-month treatment and
follow up, the study showed that those who used growth hormone lost an average
of about 5 pounds and kept it off for up to nine months. Researchers say the
weight loss was entirely caused by a loss of body fat.
In contrast, those on the placebo lost an average of only a
little more than an ounce in total body weight and less than a pound in body
fat. The loss of body fat was predominantly in the trunk and not the hips or
extremities. This type of central fat distribution is associated with
The study also showed that growth hormone improved cholesterol
profiles -- increasing the level of "good" HDL cholesterol by 19%.
There was no significant change in fasting glucose levels or insulin
resistance, which indicates diabetes risk.
Researchers say the findings show that obese people may suffer
from an abnormally low level of growth hormone in the body that may make it
harder for them to lose fat and attain a healthy cholesterol level. They say
further studies should look at the role of growth hormone as a part of
behavioral and drug-related strategies to promote weight loss.
The study was supported in part by a grant from Pfizer, Inc.,
which manufactures a growth hormone product.