A food supplement with some statin effects


DOES IT WORK?Red yeast rice and cholesterol

RED YEAST rice is made by fermenting rice with a yeast called Monascus purpureus. The resulting material is deeply red and used as a food colorant and flavour enhancer in some Chinese dishes.

Red yeast rice also has a long history of use in traditional Chinese medicine where it is believed to improve circulation and reduce blood clotting. Chinese researchers tested red yeast rice in animals during the 1990s and demonstrated reduced cholesterol levels. They tested a dried powder called Zhitai and an alcohol extract called Xuezhikang.

In the United States, a company called Pharmanex began marketing Zhitai as a proprietary product called Cholestin. The makers of prescription cholesterol-

lowering drugs called statins claimed that Cholestin violated their patent because it contained the same active ingredient.

Pharmanex stated Cholestin was a traditional food supplement, but the Food and Drug Administration (FDA) viewed it as an unapproved drug. The dispute ended up in court, with Cholestin being deemed an unapproved drug and taken off the market in the US until the required research was provided to approve it as a new drug.

However, this ruling does not apply outside the US and has led to a very confusing situation. Cholestin has been reformulated to contain no red rice yeast.

Some red rice yeast products have been found to contain little or no statins, raising questions about how they are made. Yet ironically, research conducted on authentic red yeast rice is showing that it may be particularly helpful for people with elevated cholesterol levels.

Evidence from studies

The patent debate centres on the active ingredient found in red yeast rice. The “statins” are a group of cholesterol-lowering drugs available on prescription. These drugs were originally isolated by pharmaceutical companies from yeasts related to Monascus purpureus.

Research on red yeast rice has shown that it contains several naturally occurring statins, one of which is identical to one of the prescription statins.

Early research in China showed that both Zhitai and Xuezhikang reduced total cholesterol and LDL cholesterol (“bad” cholesterol) levels, while simultaneously increasing levels of HDL cholesterol (“good” cholesterol). A small number of human studies have had similar results.

During the summer, a clinical trial of Xuezhikang was published. The study focused on elderly Chinese patients who had previously had a heart attack.

They were randomly assigned to either red yeast rice extract or a placebo. The study was stopped early because clear evidence of benefit was demonstrated after an average of about 4.5 years.

The researchers found that the risk of death from cardiac disease, and from all causes, was significantly lower among those taking Xuezhikang.

Total cholesterol was reduced by 11.3 per cent, LDL-cholesterol was reduced 21.2 per cent and HDL-cholesterol was increased by 4 per cent, all of which were significantly greater changes than in the placebo group. The side effects were rare and relatively minor.

This particular Chinese study was part of a larger, earlier study of almost 5,000 heart attack patients of all ages. Similar improvements in cholesterol levels were found in the larger study also.

Another study reported this summer gave red yeast rice or placebo to patients who had developed myalgia while taking prescription statins. Myalgia is a generalised muscle weakness and soreness that can develop with conventional statin therapy.

After six months, the patients taking the red yeast rice had significantly lower cholesterol levels, but the same incidence of myalgia as those getting placebo.

The researchers concluded that red yeast rice either contains insufficient statins to cause myalgia or other components in the extract may have a protective effect.

Problematic aspects

Red yeast rice can lead to the same side effects as prescription statins, including gastrointestinal problems, myalgia, and occasional kidney and liver damage.

People taking statins are warned not to drink grapefruit juice because it can increase the chances of adverse effects.

The same applies to red yeast rice. For these reasons, patients prescribed statins should be carefully monitored, and the same applies to those taking red yeast rice.


Red yeast rice is a food supplement for which evidence is growing to support its effectiveness. It appears to be a low-dose formulation of conventional statin drugs. However, studies have shown that products vary widely in their statin concentration.

In 2007, the FDA warned US consumers not to buy red yeast rice products on the internet because of unknown product quality.

Statins can have serious adverse effects, whether they are found in prescription drugs or food supplements.

Anyone taking red yeast rice should inform their GP and ask to be checked for early signs of any adverse effects.

  • Dónal O’Mathúna has a PhD in pharmacy, researching herbal remedies, and an MA in bioethics, and is a senior lecturer in the School of Nursing, DCU.
  • He authored Alternative Medicine: The Christian Handbook, Updated and Expanded Edition, Zondervan, 2007