French food agency warns against mass serving soy-based foods

It was at the request of the French Directorates General for Food (DGAL) and Health (DGS) that ANSES assessed the health risks of consuming foods containing isoflavones, which are known to have estrogenic hormonal activity. They are naturally present in pulses (also called legumes) and vegetables, but their content is particularly high in certain foods made from soy. The foods containing the most isoflavones are all soy-based.

The ANSES verdict was to recommend not serving soy-based foods in mass catering for all age groups.

ANSES first defined thresholds for isoflavone, below which there is virtually no risk to health. It relied on available scientific knowledge in humans and animals. Two thresholds were established, one for the general population of 0.02mg/kg of body weight per day and another, for pregnant women and women of childbearing age as well as prepubescent children, of 0.01 mg/kg of body weight/day.

These values were then compared with the dietary exposure levels of the French population.

The conclusion was that there is a risk of exceeding the thresholds among consumers of soy-based foods. Thus, 76% of children aged three to five who consume these foods exceed the threshold, as do 53% of girls aged 11 to 17, 47% of men aged 18 and over, and women aged 18 to 50. ANSES recommended against offering these foods in mass catering in order to prevent meals eaten in these settings from contributing to the risk of exceeding the threshold.

The Agency recommended diversifying plant-based foods, bearing in mind that pulses other than soy are significantly lower in isoflavones.

It is also possible to reduce isoflavones in soy-based products. For example, there are 100 times more isoflavones in soy-based snack biscuits than in soy sauce. This variability is also found within the same food due to several factors such as soybean variety, growing conditions, plant maturity, and manufacturing processes or recipe formulation.

Environmental NGOs criticised the ANSES recommendations, arguing they contradict established scientific consensus and could undermine plant-based diets, which the EU favours as a way to improve sustainability.

“Soya offers numerous health benefits, including high-quality protein and healthy fats,” says Anna-Lena Klapp, Head of Research at ProVeg International. "It’s widely recommended in dietary guidelines across the globe and is considered safe for most people.”

She said there is no similar warning for processed red meat (products such as bacon, sausage and ham), which the World Health Organization has classified as a carcinogen, and asked, "Why the double standard?"

“We would like to see large-scale meta-analyses that support this recommendation, which stands in contrast to national dietary guidelines in many countries.” 

ProVeg also noted there is no recommendation to remove red meat from mass catering, although it has been classified as a Group 2A carcinogen.

The European Vegetarian Union said that ANSES is pushing for severe restrictions of soy products in schools, in a move that defies the current scientific consensus about this legume, and called on the medical community to set the record straight.

"Soy-based foods have been safely consumed around the world for centuries", Michela Bisonni, director of Plant Based Foods Europe, said to the Euractiv news site.

For her, the decision was taken "without considering the full set of evidence".

ANSES said it endorses the conclusions of its Expert Committee (CES) on "human nutrition", which conducted a systematic review of consumption of soy-based infant formulas compared to breast milk or a soy-free infant formula. This review identified, with a weak weight of evidence, an increased risk of early menstruation (before the age of 12) and a change in the development of certain sexual markers (growth and maturation of reproductive tissues and organs) in children who consumed soy-based infant formulas.