Phytosterols are natural compounds found in plants, especially nuts and oil seeds. Phytostanols are the product of the hydrogenation of phytosterols. As these compounds have a structure similar to that of cholesterol, they compete with cholesterol in the intestine and thus limit its absorption.
On the basis of the available scientific literature, European regulations authorise the claim that phytosterols and phytostanols lower blood cholesterol and that lowering blood cholesterol can reduce the risk of coronary diseases.
In order to address certain concerns, the consumer association UFC-Que Choisir decided to request that ANSES assess the risks and benefits of consuming food products fortified with phytosterols and phytostanols.
Market and consumption data
An analysis of the French market for products fortified with phytosterols shows that it is currently concentrated in three sectors: margarines, fresh dairy products and assimilated products, and condiment sauces (such as vinaigrette, mayonnaise, ketchup), and accounts for about 4% of their respective market shares.
According to the INCA 2 study (individual and national study of food consumption in France) carried out by ANSES, consumers of these products in 2006-2007accounted for about 3% of adults and 0.7% of children. Among the adults, the age range 46-79 years, which may be considered most at risk of hypercholesterolaemia, was the most heavily represented. Children made up 12.5% of consumers of foods fortified with phytosterols.
A collective expert appraisal revealing several uncertainties
While phytosterols do indeed contribute to a mean reduction of about 10% in total blood cholesterol levels and in circulating LDL cholesterol (commonly known as “bad cholesterol”), there is considerable individual variability in responses to phytosterols. In about 30% of subjects, the consumption of foods fortified with phytosterols does not lead to a reduction in LDL cholesterol.
The consumption of foods fortified with phytosterols also leads to an increase in plasma concentrations of phytosterols, for which the consequences on cardiovascular risk are unknown.
Furthermore, a reduction in plasma concentrations of β-carotene is also observed following consumption of phytosterols, which is likely to increase cardiovascular risk.
Lastly, there are no studies concerning the direct effects of phytosterols on cardiovascular events that would make it possible to take a position on the results of the effects of phytosterols on all these intermediate parameters (LDL cholesterol, plasma phytosterols, plasma β-carotene). At present, it is therefore not possible to reach a conclusion on the effects of phytosterols on the prevention of cardiovascular risk.
ANSES’s conclusions and recommendations
Faced with these scientific uncertainties, ANSES considers that in terms of public health the data currently available do not make it possible to consider that foods fortified with phytosterols are a suitable means of prevention of cardiovascular diseases in the population as a whole.
While blood LDL cholesterol is considered to be a risk factor for cardiovascular disease, ANSES reiterates that these diseases are multifactorial, involving a large number of both risk factors and protective factors. As a result, reducing a single risk factor does not necessarily reduce the risk of disease.
The Agency also reiterates that there are several recognised health and dietary measures that act as levers for prevention, such as stopping smoking, increasing physical activity, reducing sedentary behaviour and improving dietary balance by ensuring sufficient consumption of fruit and vegetables, a balanced intake of fatty acids and moderate consumption of sugar and salt. At individual level, it is doctors’ responsibility to adapt the different measures to their patients with hypercholesterolemia.
ANSES therefore recommends:
- that people concerned about their cholesterol levels should consult a health professional who will be able to recommend the most suitable health and dietary measures for their situations;
- that consumers of products fortified with phytosterols make sure that they consume at the very least the quantities of fruit and vegetables recommended by the French National Health and Nutrition Programme (PNNS) in order to compensate for the reduction in β-carotene caused by consuming these products;
- avoiding the consumption by children of products fortified with phytosterols;
- avoiding the consumption of products fortified with phytosterols by pregnant or breastfeeding women.