Topic Overview
What is beta-sitosterol plant
extract?
Beta-sitosterol is one of many sterols (phytosterols) that come
from plants and have a structure like the cholesterol produced in the body. You
can find phytosterols in most plants and thus in foods such as rice bran, wheat
germ, corn oils, soybeans, and peanuts. Beta-sitosterol is also available as a
dietary supplement.
What is beta-sitosterol used for?
Beta-sitosterol is said to lower
cholesterol levels and reduce the risk of colon
cancer. It also is said to relieve symptoms of
benign prostatic hyperplasia (BPH), such as waking up
many times at night to urinate. How beta-sitosterol works is not known. It may
be related to cholesterol
metabolism or anti-inflammatory effects.
There is limited evidence that beta-sitosterol does relieve the
symptoms of BPH.1 Research supports the fact that
phytosterols, including beta-sitosterol, can reduce cholesterol levels. One
study found no evidence that phytosterols reduce the risk of cancer.2
Is beta-sitosterol safe?
Few problems have been reported among men taking beta-sitosterol
for BPH. Some men may have problems with their stomach and digestion.
Beta-sitosterol's ability to prevent complications of BPH is not known.
Men who have problems urinating should see a doctor to rule out
prostate cancer or other diseases. Prostate cancer is treatable, but treatment
may be more successful when you find and treat the cancer as early as possible.
The Natural Health Products Directorate (NHPD), within the Health
Products and Food Branch of Health Canada, regulates dietary supplements in
Canada. Dietary supplements, including beta-sitosterol, must be reviewed and
approved by the NHPD before they can be sold in Canada.
Always tell your doctor if you are using a dietary supplement or if
you are thinking about combining a dietary supplement with your conventional
medical treatment. It may not be safe to forgo your conventional medical
treatment and rely only on a dietary supplement. This is especially important
for women who are pregnant or breast-feeding.
When using dietary supplements, keep in mind the following:
- Like conventional medicines, dietary
supplements may cause side effects, trigger allergic reactions, or interact
with prescription and non-prescription medicines or other supplements you might
be taking. A side effect or interaction with another medicine or supplement may
make other health conditions worse.
- The way dietary supplements
are manufactured may not be standardized. Because of this, how well they work
or any side effects they cause may differ among brands or even within different
lots of the same brand. The form of the supplement that you buy in health food
or grocery stores may not be the same as the form used in research.
- Other than for vitamins and minerals, the long-term effects of
most dietary supplements are not known.