NEW YORK (Reuters Health) - Testosterone
supplementation could one day help keep men fit, active
and happy well into old age, just as estrogen lends
vitality to postmenopausal women, a doctor suggests.

Between age 20 and 70, a man's testosterone level may
drop as much as 50%. A growing number of medical
professionals refer to this decline as
``andropause''--analogous to menopause in women.

However, hormone replacement therapy for men remains controversial. Some
researchers suspect extra testosterone could spur the growth of prostate cancer,
and the illicit use of the hormones by bodybuilders and other athletes has also
tainted its image.

According to Dr. Malcolm Carruthers, carefully monitored testosterone
supplementation for men deficient in the hormone is safe and has many health benefits.

`It's not only okay for the prostate; it's actually good for the heart and circulation,
prevents osteoporosis, and has many of the benefits--including possibly
preventing Alzheimer's--that female hormone replacement therapy does,''
Carruthers, a physician and chemical pathologist in private practice in London,
told Reuters Health.

Carruthers has launched a charity, The Andropause Society, to study and
support research in this area. He is also a consultant to AndroScreen.com, a Web
site offering information on screening for testosterone deficiency and access to
treatment, and is working on building a worldwide network of doctors trained in
treating testosterone deficiency.

Indeed, a growing body of evidence supports the idea that testosterone
supplementation for men with low levels of the hormone can strengthen bone,
increase muscle mass, improve cognitive function and libido, and fight
depression, according to Dr. Natan Bar-Chama. Bar-Chama is director of male
reproductive medicine and surgery at the Mt. Sinai School of Medicine in New York.

``The field of andropause is in its early stage,'' the New York researcher told
Reuters Health. ``We're probably a decade behind as compared to the field of
menopause.'' He said he expects interest in this area to grow dramatically in the
next 5 to 10 years.

Although long-term studies on the risks of testosterone supplementation are not
yet complete, Bar-Chama said, early results do not suggest it carries an
increased risk of prostate cancer.

New testosterone gels and patches have made testosterone supplementation
safer, Bar-Chama added. These medications increase testosterone but not beyond
physiologically normal levels, as pills and injections have the potential to do.

Deciding who would benefit from testosterone supplementation requires looking
at symptoms as well as hormone levels, both doctors agree.
Testosterone levels vary from person to person, and a man with normal levels
may have symptoms of deficiency. These symptoms include depression, loss of
interest in sex, poor mental function, osteoporosis and reduced muscle strength,
according to Carruthers.

Evaluation of many factors, including muscle/fat ratio, bone density, mental
function and sexual performance, is necessary to determine if a man needs extra
testosterone, Bar-Chama said.

Testosterone's benefit of reducing fat and increasing muscle mass is not just
cosmetic, he observed. Trimming fat and adding muscle can help prevent or
slow the progress of heart disease.

``There are many men who can benefit from testosterone supplementation,''
Bar-Chama said. ``There are tremendous benefits but there are also risks.''

As the field of andropause develops, Bar-Chama predicts, doctors will more
clearly define these risks and benefits and begin to reduce these risks, just as
researchers working on menopause have worked to shrink the side effects of
estrogen supplementation.