MEDICAL NEWS:
STUDY INDICATES WIDELY-USED NUTRITIONAL SUPPLEMENT DOES NOT IMPROVE
CHOLESTEROL LEVELS
May 18, 2006 — A new study suggests that use of the nutritional supplement
policosanol does not lower cholesterol levels any more than placebo, apparently
contradicting the results of previous studies, according to a study in the May
17 issue of the Journal of the American Medical Association.
Policosanol is a natural substance produced from the waxy coating of sugar
cane. Cuban sugar cane policosanol is sold in more than 40 countries mainly
because of its supposed lipid-lowering effects, according to background
information in the article. Numerous policosanol products from a variety of
sources (sugar cane, wheat germ, rice bran, beeswax) are available
over-the-counter and on the Internet in several countries. Advertising
emphasizes predominantly its reputed lipid-lowering effects, comparable with
statins (prescription medications taken to lower cholesterol). Most of the
published scientific literature, more than 80 trials, supporting the beneficial
effects of policosanol on lipids has been authored by a single research group
from Cuba. One clinical trial from the Netherlands showed wheat germ-derived
policosanol ineffective in lowering total cholesterol and low-density
lipoprotein cholesterol (LDL-C), sometimes called "bad" cholesterol.
Heiner K. Berthold, M.D., Ph.D., of the University of Cologne, Germany, and
colleagues conducted a study to determine the lipid-lowering effects of
policosanol. The multicenter, randomized, double-blind, placebo-controlled,
trial included 143 patients with hypercholesterolemia (high cholesterol) or
combined hyperlipidemia (excess of fats or lipids in the blood) having baseline
LDL-C levels of at least 150 mg/dL and either no or one cardiovascular risk
factor other than known coronary heart disease, or baseline LDL-C levels of
between 150 and 189 mg/dL and two or more risk factors. The patients were
randomized into five groups: 10, 20, 40, or 80 mg/d of policosanol or placebo.
The study was conducted from September 2000 to May 2001.
In none of the five treatment groups did LDL-C levels decrease more than 10
percent from baseline. No statistically significant difference between
policosanol and placebo was observed. In none of the secondary outcome measures,
namely total cholesterol, high-density lipoprotein cholesterol (HDL-C; known as
"good" cholesterol), very low-density lipoprotein cholesterol, triglycerides,
lipoprotein(a) (a family of lipoprotein particles varying in density and size),
and ratio of total or LDL-C to HDL-C, were there any significant effects of
policosanol. Policosanol was tolerated well and no severe adverse events
occurred.
"Our results suggest that [policosanol] is devoid of clinically relevant
lipoprotein-lowering properties in white patients. Still, more independent
studies are required to counterbalance the vast body of available positive
trials. Although policosanol has been used for more than a decade in clinical
trials, there are still no data on patient-related outcomes, such as
cardiovascular morbidity and mortality. Moreover, independent information should
be given to consumers who might take policosanol to improve their cardiovascular
risk profile," the authors conclude.
|