What is monacolin k
Jan 13, 2022

What is monacolin k

Monacolin K has been specified as the food constituent in RYR preparations which is responsible for the claimed effect on the maintenance of normal blood LDL-cholesterol concentrations. In assessing the safety of monacolins, the Panel considered monacolin K and lovastatin identical, the latter being the active ingredients of medicinal product authorised in the EU for the treatment of hypercholesterolaemia. The Panel noted that in the health claim (EFSA NDA Panel, 2013), the intake of monacolin K is 10 mg/day for the maintenance of normal blood LDL-cholesterol concentrations. This intake of monacolin K overlaps the lowest therapeutic dose of 10 mg/day of lovastatin indicated as the starting dose for the treatment of hypercholesterolaemia (SPC for lovastatin, online).

The effect of other possible ingredients of food supplements on monacolins bioactivity is not considered in this opinion.


How does monacolin k work

Red yeast rice is made by culturing rice with various strains of the yeast Monascus purpureus. Some preparations of red yeast rice are used in food products in Chinese cuisine, including Peking duck. Others have been sold as dietary supplements to lower blood levels of cholesterol and related lipids.

Some red yeast rice products contain substances called monacolins, which are produced by the yeast. Monacolin K is chemically identical to the active ingredient in the cholesterol-lowering drug lovastatin, which is one of the drugs in the category known as statins. These drugs lower blood cholesterol levels by reducing the production of cholesterol by the liver.

The composition of red yeast rice products varies depending on the yeast strains and culture conditions used to manufacture them. The strains and conditions used to produce culinary red yeast rice differ from those used to produce products that are intended to lower cholesterol. Tests performed by the FDA indicate that the red yeast rice sold as a food product contains only traces of monacolin K or none at all.

Monacolin K in Red Yeast Rice

What foods contain monacolin k

Some red yeast rice products contain substantial amounts of monacolin K, which is chemically identical to the active ingredient in the cholesterol-lowering drug lovastatin. These products may lower blood cholesterol levels and can cause the same types of side effects and drug interactions as lovastatin.

Other red yeast rice products contain little or no monacolin K. It is not known whether these products have any effect on blood cholesterol levels.

Consumers have no way of knowing how much monacolin K is present in most red yeast rice products. The labels on these products usually state only the amount of red yeast rice that they contain, not the amount of monacolin K.

The U.S. Food and Drug Administration (FDA) has determined that red yeast rice products that contain more than trace amounts of monacolin K are unapproved new drugs and cannot be sold legally as dietary supplements.

Some red yeast rice products contain a contaminant called citrinin, which can cause kidney failure.

Tell all your health care providers about any complementary health approaches you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care.

How much monacolin k in red yeast rice

In a 2014 paper published in the Journal of Pharmaceutical and Biomedical Analysis, researchers from the University of Mississippi, Harvard Medical School and the China Food and Drug Administration divulged the amount of monacolin K in supplements labeled as containing 600 mg of red yeast rice ranged more than 40-fold from 0.03 mg to 2.18 mg.

That the amount of monacolin K differs among various supplement brands does not indicate the products were manufactured in violation of FDA regulations.

“Variations in the concentrations of phytochemical constituents in dietary supplements have to be expected, since differences in raw material quality and manufacturing processes will affect the composition substantially," Gafner of ABC explained.

monacolin k red yeast rice

Is monacolin k safe

The Panel concluded that exposure to monacolin K from RYR could lead to severe adverse effects on musculoskeletal system, including rhabdomyolysis, and on the liver. In the reported cases, the product contained other ingredients in addition to RYR. However, these reported effects in particular musculoskeletal effects, have both occurred after ingestion of monacolin K and lovastatin independently. On the basis of the information available and several uncertainties highlighted in this opinion, the Panel was unable to identify a dietary intake of monacolins from RYR that does not give rise to concerns about harmful effects to health, for the general population, and as appropriate, for vulnerable subgroups of the population.

Monacolin k benefits

High cholesterol (hyperlipidemia). Research shows that red yeast rice containing considerable amounts of monacolin K can lower your total blood cholesterol level, your low-density lipoprotein (LDL, or "bad") cholesterol level and your triglyceride level.

Monacolin k vs Lovastatin

The primary monacolin in red yeast rice is monacolin K, which has the same chemical structure as lovastatin. Although levels of lovastatin vary in the product, 2.4 g of red yeast rice daily may contain about 4.8 mg of lovastatin, or 0.2% of the total dose.

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