"Erase the signs of aging", "fight against sagging skin", "prevent the appearance of wrinkles", "rejuvenate the face", strengthen nails and hair... The promises are enticing. Already popular for a long time in anti-aging skincare formulations, collagen has reappeared in recent years in the form of food supplements to drink, capsules, or snacks. Promoted by mainly American celebrities (notably Jennifer Aniston, who has become the ambassador of one of the leading brands of powdered collagen in the United States), it has also established itself in the beauty routine of French women, after having been marketed by many trendy cosmetics brands.
Originally, collagen is an essential protein naturally present in the body, responsible for the structure, flexibility and strength of many tissues (such as skin, bones, tendons, ligaments, cartilage, etc.). But its production decreases with age, hence the interest in making up for this loss by doing a small cure, several months a year. Or not, according to UFC-Que Choisir, which completely contradicts the alleged virtues promoted by brands, in a survey published on January 10.
'No reason for it to work'
While brands assure that the effects on the skin of their collagen cure are clinically proven, UFC-Que Choisir is not convinced, denouncing "outrageous marketing" and "dishonest scientific arguments". This would be evidenced, first of all, by the weakness of the resources on which to rely. Of the three brands that the organization asked to provide clinical studies demonstrating benefits in slowing the signs of skin aging, two of them did not respond. The third sent documents whose methodology was deemed "insufficient" by our colleagues.
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As for the health benefits of collagen, including "comfort" or "alleviation of joint pain," the report says, "the few clinical trials that can be found, on osteoarthritis pain for example, are poorly conducted, on too few patients, without comparing the results of collagen with those of a placebo," the report reads. It also adds that products claiming to 'strengthen bone density' on their packaging are problematic, as this statement is prohibited on a food supplement, falling within the scope of the therapeutic claim. Contacted by UFC-Que Choisir, the honorary president of the French Society of Rheumatology, Professor Francis Berenbaum, decided: "There is no proof that it works. And, most importantly, there's no reason for it to work."
In particular, it is the ingestion of the protein by the body that is called into question. "The body is not able to assimilate collagen in this form," explains Dr. Claire Vinatier, a researcher in the Inserm Regenerative Medicine and Skeleton Unit at Nantes University, in an interview still reported by UFC Que Choisir. "When collagen is ingested, it is treated like any other protein: it is broken down into amino acids so that it can pass through the intestinal barrier. Once assimilated, these amino acids can be used to rebuild proteins, but not collagen more specifically than any other," she says.
'Manipulations'
Finally, the article denounces the "manipulations" of certain brands to sell these products through a "misappropriation of scientific language". For example, those that recommend favouring products 'with a molecular weight of less than 2,000 daltons', preferably peptides derived from hydrolysis' and 'ideally type 1'. These terms certainly exist in scientific jargon, but are considered incomprehensible to "the average person" according to the consumer association.
Some references are also said to be "pure inventions", such as an alleged certificate of conformity drawn up by the "French Directorate General for the Safety of Food Products", highlighted on the website of a collagen specialist. While the Directorate-General for Food (DGAL) does exist and so does the National Agency for Food Safety (ANSES), the "French Directorate-General for the Safety of Food Products" does not exist. The same brand also claimed to supply its product to a clinical trial conducted at the Georges-Pompidou Hospital in Paris... of which UFC-Que Choisir has not been traced, and whose information has been denied by the press service of the health establishment.
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