Red yeast rice, a dietary staple in many Asian countries, has been hailed as an alternative for managing cholesterol due to the naturally occurring presence of monacolin k (MK), the active compound that is chemically identical to cholesterol drug lovastatin.
However, there is a lack of harmonisation across European countries regarding the permitted dosage of MK in food and dietary supplements.
A 2011 EFSA opinion confirmed that a 10 mg daily intake of MK was beneficial in maintaining normal cholesterol levels, but the European Commission has not legislated on limits for supplements.
A drug in France, food in Italy
In Italy the maximum legal limit for MK in food stuffs and dietary supplements is 10 mg, while in France, supplements containing 10 mg or more of MK are considered to be prescription-only drugs.
In Switzerland and Iceland, health authorities do not permit any levels of MK in food supplements on the grounds that they contain a pharmacologically active substance.
In most other countries, including the Netherlands and Latvia, there is no upper limit, however it is frequently mandatory for companies to prove that the level does not correspond to a medicinal dosage - usually 10 mg due to the existence of drugs containing 10 mg of lovastatin.
According to Jérôme Le Bloch, from Nutraveris’ health claim and food safety department, this creates a lack of clarity for consumers.
“EFSA must define what is the legal dosage used in food supplements. If there is a clear difference between the legal food dosage and the drug dosage, it will be clearer for manufacturers and safer for consumers. We need one opinion and not 28.”
Concern over varying doses
Even within the dietary supplement sector there is scope for confusion as the MK level often differs from the level stated on the packaging, if it is stated at all.
A 2010 study by R Gordon et al. measured MK levels in 12 commercially-available red yeast rice (RYR) products and found huge discrepancies, with levels ranging from 0.10 mg/capsule to 10.09 mg, meaning that the latter product was in fact an unapproved drug.
One reason for such inconsistencies in MK levels is due to a lack of standardised production methods. Red yeast rice is a mould grown on white rice and the quality and concentration of MK depends on both the length and conditions of the fermentation process.
“The differences observed in studies may be explained by the various origins of the products. RYR from China varies widely in quality and dosage, while European production is more stable,” says Le Bloch.
However, a 2013 review of red yeast rice by ANSES, the French Food Safety Authority, also noted that there are methodological difficulties in determining levels precisely.
“Several different methods are used to assay monacolins in finished products. Therefore it is currently impossible to determine unambiguously the levels of monacolin, including monacolin K, in a food supplement containing ‘red yeast rice.’”
“The composition declared by manufacturers lacks precision and the actual levels of monacolins are mostly unknown,” said the study.
In Gordon et al. study, the researchers suggested that manufacturers in the US may deliberately choose not to state MK levels on packaging in order to avoid being classified as a drug.
Whatever the reason, it means that consumers are often not aware of the levels they are ingesting.
For some, harmonising production methods could be one way of exercising a degree of control over a complicated situation.
“There is no clear and validated methodology to assess monacolin content of red yeast rice product. The solution may be a harmonisation of production methods because the fermentation process is very important; If we can do this then we will have a more accurate idea of what is in the products. That’s why a European harmonisation is required,” said Le Bloch.
NutraIngredients contacted the European Commission to see whether it was considering reviewing the legislation on maximum limits of MK in red yeast rice food supplements but it was unavailable for comment.