Antioxidant May Help Lower Blood Pressure
Supplement May Reduce Dependence on Blood Pressure-Lowering Drugs
Feb. 20, 2004 -- Taking an antioxidant supplement made from the
bark of French pine trees may help people with high blood pressure reduce their
dependence on medications taken to keep their blood pressure under control, new
The study shows that people with high blood pressure who took
the supplement, called Pycnogenol, were able to lower their daily dose of blood
pressure-lowering medications by more than 30% while still keeping their blood
pressure within normal levels.
Researchers say the supplement contains a high concentration of
polyphenols, a type of antioxidant also found in foods such as grapes, and
flavonoids, such as those found in green tea. Mounting studies have shown that
these plant-based antioxidants may have a number of healthy effects, including
lowering cholesterol levels and improving circulation.
By lowering the dependence on blood pressure-lowering drugs
with natural antioxidants, researchers say it may be possible to reduce the
side effects as well as the cost of treating high blood pressure.
Antioxidant Supplement Helps Lower Blood Pressure
In the study, researchers looked at the effects of daily
supplementation with 100 milligrams of Pycongenol or a placebo in a group of 58
adults with high blood pressure who were also treated with a calcium channel
blocker, nifedipine (sold commercially as Adalat and Procardia).
All of the participants started with a 20-milligram daily dose
of the calcium channel blocker and their dosage was either increased or
decreased every two weeks until their blood pressure reached normal levels.
After 12 weeks of treatment, those who received the antioxidant
supplement in addition to their medication were able to keep their blood
pressure within normal levels with a 15-milligram dose of the drug compared
with an average dose of 21.6 milligrams per day among those who took the
Researchers say the blood pressure-lowering effects of
Pycongenol appeared to be caused by the antioxidants effect on the endothelium,
the innermost layer of arterial blood vessels that expands and contracts in
response to blood flow.
"They produced less of the substances that constrict
arteries and more of the substances that dilate [expand] the arteries,"
says researcher Peter Rohdewald, PhD, retired professor of pharmaceutical
chemistry at the University of Münster in Germany. "That recovery of the
function of the endothelium is probably the most beneficial effect for the
The study, which appears in the Jan. 2 issue of the journal
Life Sciences, showed side effects that were similar in the two
Rohdewald says the most powerful ingredient in the antioxidant
supplement appears to be procyanidins, which are bitter tasting compounds that
used to be commonly found in many foods.
"My theory is that our food industry and our plant
cultivation over past 200 years has nearly eliminated these very useful
substance because most people don't like to eat astringent-tasting apples and
grapes. They like to have sweet ones," Rohdewald tells WebMD.
"I think for our well-being these procyanidins had been
very useful. Now we lack these substances, and we would do better if we take
these substances," says Rohdewald, who also serves a consultant to the
company that produces Pycnogenol.