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Saw palmetto - all you need to know

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Saw Palmetto has a long history of fold use. Native Americans values it for treating disorders of the urinary tract. Early colonists, noting the vitality of animals who fed on the berries, gave the fruits to frail people as a general tonic. Today saw palmetto’s claim to fame rests with its ability to relieve the symptoms of an enlarged prostate gland – a use verified by many scientific studies.

Where does it come from?
The saw palmetto, a small palm tree that grows wild in the southern USA, gets its name from the spiny saw-toothed stems that lie at the base of each leaf. With a life span of 700 years the plant seems almost indestructible. Its medicinal properties are derived from the blue-black berries, which are usually harvested in August and September.

How does it work?
The fruit contains a rich mixture of phytosterols that block the action of an enzyme which is found in the prostate gland. This enzyme converts the male hormone, testosterone, to another powerful hormone (dihydrotestosterone), which stimulates prostate growth. Saw palmetto is thought to help stop this increase in prostate size. Researchers also believe saw palmetto relaxes the gland to reduce spasm. As a result of both these actions saw palmetto extracts can improve lower urinary tract symptoms in men.

What can it help?
BENIGN PROSTATE ENLARGEMENT: After the age of 45, the number of cells in the prostate tends to increase and the gland can start to enlarge, interfering with urinary flow. As many as one in two men are affected by the age of 60 and four out of five men have evidence of prostate enlargement by the age of 80. Typically, symptoms include urinary hesitancy, frequency, urgency and poor flow. A number of studies have shown that saw palmetto is significantly better than placebo for improving male lower urinary tract symptoms. It is particularly helpful for reducing the need to visit the bathroom at night (nocturia) which is one of the most annoying symptoms for men – and their bed partners whose sleep is disturbed.

GENERAL PROSTATE HEALTH: Saw palmetto can also be taken as a general measure to help maintain a healthy prostate gland and reduce the development of bothersome urinary symptoms.

Are there any side effects?
Saw palmetto fruit extract improves urinary symptoms without affecting circulating blood levels of another enzyme called prostate specific antigen (PSA). This means that taking saw palmetto does not affect this important screening test for prostate cancer.

How should I take it?
A beneficial effect is usually noticeable within six weeks. Avoid cheap versions of saw palmetto which may contain inactive extracts from the leaves rather than the fruit.


GOOD FOR: The need to urinate frequently (especially at night). Weak or interrupted urinary flow. A feeling that you cannot empty your bladder completely

WATCHPOINT: If you are taking medicine for an enlarged prostate, talk to your doctor before taking saw palmetto.

WHAT TO BUY: Saw palmetto capsules differ in strength and quality, so make sure your buy a registered traditional medicine, such as Healthspan’s Saw Palmetto Complete.

Simon started as Exeter’s first herbal practitioner in 1977, after finishing his medical sciences studies at Cambridge, and has worked in practice ever since. In the last thirty years he has also become an authority on herbal medicine, co-written the two standard textbooks used around the world, and has been a leading figure in herbal medicine associations in the UK.

Simon is a herbal practitioner with The Sustainable Health Centre in Exeter.

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