When it comes to controlling cholesterol levels, mention is made of red yeast rice-based supplements, as they are presented as a *natural* alternative to reference drugs (statins) to treat this problem. However, It is by no means a new remedy: already in the pharmacopoeia treatises of ancestral China it was alluded to as a *soft and useful substance to improve blood circulation*.
The key to this and other beneficial effects attributed to it lies in a substance, monacolin, *although the most correct would be to use the term monacolins, since it is a family of substances (more than ten) that are extracted from fermentation of the rice with the Monascus purpureus yeast, giving the rice a red hue. Among this group of monacolins, monacolin K stands out, which has been used in Asia for centuries for different purposes: for meat preservation, as a food colouring, as a flavor enhancer and also as a medicinal substance*explains Mar Blanco Rogel, a pharmacist and associate professor on the UOC’s master’s degree in Nutrition in Physical Activity and Sport.
monacolin and cholesterol
Regarding its potential to control blood cholesterol levels, the expert contextualizes its use, recalling that, in general, it is recommended to maintain cholesterol levels below 200 mg/dl. *Between 200 mg/dl and 239 mg/dl, the cholesterol level is considered high or borderline, so it is advisable to reduce it through hygienic-dietary measures and healthy habits. At these levels there is already talk of hypercholesterolemia, and that is when supplements based on red yeast rice could be recommended. Regarding higher levels, a cholesterol of 240 mg/dl or more is considered high, making it necessary to take pharmacological and hygienic-dietary measures to reduce it*.
Therefore, the group of patients in which, according to different studies, there is evidence that this substance is effective in reducing cholesterol levels and in which, consequently, its consumption would be recommended, are people with diagnosed hypercholesterolemia (that is, with cholesterol levels of 200 mg/dl – 239 mg/dl). *In these cases, it has been shown that supplementation with red yeast rice for a period of at least eight weeks can reduce both total and LDL cholesterol (the “bad”) by 20%*, says Mar Blanco Rogel .
Basically, the mechanism of action by which red yeast fermented rice produces this effect lies in the inhibitory activity that monacolin has with respect to hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase, *which is the enzyme responsible for the synthesis of endogenous cholesterol*, points out the expert. This action of monacolin contributes to maintaining normal blood cholesterol concentrations.
Differences and similarities with statins
The usual *cover letter* of red yeast rice is as an alternative to statins, which are currently the pharmacological group of choice in the approach to hypercholesterolemia. The main similarity between both options is that they have the same therapeutic objective: the reduction of high blood cholesterol levels. But there are important differences between the two: *Monacolins, and, among them, specifically monacolin K, are a type of lactone, and have an identical shape to lovastatin, which is a drug belonging to the statin family, which are the reference options in the treatment of hypercholesterolemia*, affirms Blanco Rogel.
*However*, continues the specialist, *red yeast rice extracts not only provide monacolin K, but also other substances that provide antioxidant activity, which is important to prevent cholesterol from oxidizing (oxidized cholesterol is directly related to the appearance of arteriosclerosis)*.
Currently it is possible to find these supplements in different formats (capsules, sticks*). The choice of one or the other depends on personal preferences. *Regarding the dosage, there are several, depending on whether the red yeast rice is consumed alone or accompanied by other substances such as policosanols, berberine, resveratrol, coenzyme Q10, group B vitamins… The The most common dosage, and with a proven effect, on the regulation of cholesterol is 10 mg/day, as established by Regulation 432/2012 of the European Commission, of May 16, 2012*.
The UOC professor comments that, *despite the accumulated scientific evidence, harmonization of monacolin K in food supplements in terms of maximum dosage levels is still pending in Europe. It is even possible that, at the beginning of 2022, these maximum values of monacolin will be reduced to 3 mg/day, which will decrease its activity*.
In relation to this, Blanco Rogel points out that, *even if a product has low doses of monacolins, it does not imply that it is not effective. It is possible that the other ingredients of the formula act in synergy to reduce cholesterol levels, such as policosanols from sugar cane, berberine, fibers…*.
Interactions, side effects and other precautions for use
The fact that it is a non-pharmacological substance does not imply that it is suitable for everyone. As Mar Blanco Rogel comments, it is recommended that the intake of these supplements be supervised by a doctor or other health professional.
*In people sensitive to this substance, its consumption can lead to side effects such as nausea, gas, diarrhea or constipation. In addition, some people may be intolerant, although this is a rare situation, and in these cases the intake leads to muscle and liver disorders*, warns the expert.
It should also be taken into account that this supplement favors a series of interactions: *For example, it can interact with grapefruit juice and, also, with a type of medicine, CYP3A4 inhibitors (such as those used to treat hypertension arterial), as it could lead to increases in monacolin levels and therefore increase the risk of side effects. It should also not be taken together with cholesterol-lowering drugs such as statins, as the combination could enhance side effects. Likewise, this supplement is contraindicated for pregnant or lactating women, in children or adolescents and in people over seventy years of age*, says Blanco Rogel.
Around with the citrinin
Another issue related to the composition of these supplements that is currently under review is their citrinin content, which, as Mar Blanco Rogel explains, is a nephrotoxic mycotoxin that occurs as an undesirable contaminant in the fermentation products of the Monascus purpureus fungus (such as red yeast rice), and can also be found in fermented products of various Aspergillus, Penicillium, and Monascus species.