THOMAS LYNCH MEN'S HEALTH MATTERSYour health questions answered
Q I recently read that saw palmetto, a herbal remedy for prostate disease, can affect the accuracy of a PSA blood test for prostate cancer. Is this true?
AThere's reason to suspect that saw palmetto might affect prostate specific antigen (PSA) levels, but to date we have little scientific evidence that this herbal remedy interferes with the cancer screening blood test.
The extract of the saw palmetto plant (Serenoa repens) is often recommended for disorders of the prostate gland. Medical studies have reached different conclusions about its effectiveness, but most experts believe it is a safe and effective treatment, particularly for benign prostatic hyperplasia (BPH).
Very little is known about how and why saw palmetto is useful for prostate conditions. Some research suggests that the extract blocks the effects of testosterone within the prostate, much like the drug finasteride (Proscar). Finasteride, in turn, can lower blood levels of PSA.
Since PSA is often used to screen for prostate cancer, men who take finasteride for prostate conditions are often warned that their PSA levels may not be accurate for detecting early stage cancers.
Despite its widespread use, there has been little scientific research looking at how saw palmetto affects PSA levels. A single study that compared finasteride and saw palmetto for chronic prostatitis found that saw palmetto had slightly less impact on PSA levels.
That said, it's impossible to know whether doctors should use a different PSA cut-off in men taking the herbal extract.
There's also some question as to whether saw palmetto might actually help to prevent prostate cancer, although there's been little research on this connection, either.
The bottom line is that men who are thinking about long-term treatment with saw palmetto should consult their doctor. It may make sense to check a PSA level before taking the drug. However, it is unlikely that taking saw palmetto will lead to wildly inaccurate PSA results, or a missed diagnosis of prostate cancer.
Q I am 42 years old and have just had my cholesterol checked. What is cholesterol, why is it so important and how does it affect my heart?
ACholesterol is a fat, which is a normal part of any diet and normal levels are needed in many animals and in man. High cholesterol levels, however, have been identified for more than 50 years as likely to lead to a higher risk of heart attack, stroke and peripheral vascular disease (blockages in the legs).
It seems that when high levels of cholesterol have been present for many years, cells stuffed with fat become embedded in arteries in the heart and head.
Over time, this deposition of fat will lead to blockages in these arteries, which in turn leads to heart attacks and/or stroke. This type of buildup is one of the leading killers in the western world.
Teenagers in western society start to build up "fatty streaks" in their major blood vessels, which will later lead to real problems. The real issue is that "normal" cholesterol levels in the western world are, in historical and evolutionary terms, very high. The Bantu and Kalahari Bushmen (with whom we share the same genetic make-up) have cholesterol levels about half of what we would consider to be normal, and they have no coronary disease.
Our western diet has led to very high levels of cholesterol from an early age. There is "bad" cholesterol which is called low-density lipoprotein (LDL) as well as good cholesterol, high-density lipoprotein (HDL). It is the balance between the two which is important.
Cholesterol is one of the real "treatable" factors to help decrease the incidence of coronary disease.
Strict diet alone can be very successful in lowering your cholesterol levels and the key issue is to minimise your intake of animal fats such as butter and to eat moderate amounts of red meat. Exercise is also important. In the past 15 years, effective medications have become available which markedly reduce cholesterol.
• This weekly column is edited by Thomas Lynch, consultant urological surgeon, St James' Hospital, Dublin with a contribution from Dr Ross Murphy, consultant cardiologist. Please send your questions to healthsupplement@irish-times.ie