Expensive food supplements that promise to tackle the signs of ageing skin could be a waste of money, new research has suggested.

The paper, published in the March edition of the peer-review journal Nutrition Bulletin, concluded that orally consumed beauty supplements - known as nutraceuticals for the skin - may not add further benefit to the effects already obtained from a balanced diet, sunscreen and healthy lifestyle.

Researchers from the British Nutrition Foundation examined published scientific evidence on the beneficial effects of nutraceuticals on skin appearance and found that Vitamins A, C, B2, B3, B7 and the minerals iodine and zinc had ‘authorised skin-related health claims’.

However, scientists found little evidence to suggest that ingredients such as green tea extract, pomegranate extract, carotenoids, evening primrose oil, borage oil, fish oil, collagen and co-enzyme Q10 had any effect in supplement form, though they could be beneficial as part of a healthy diet.

“To date, the evidence for many ingredients in relation to skin appearance is limited, not sufficiently robust and/or inconsistent,” the paper stated.

“Although there are a small number of human studies suggesting a potential benefit and some plausible biological mechanisms, much of the evidence to date comes from animal and in vitro studies. There are simply not enough good quality randomised controlled trials in this area to draw firm conclusions about the benefit of nutraceuticals to skin appearance.” The global beauty supplements market is expected to reach $7,100m by 2023. “As consumers can spend hundreds of pounds a year on oral beauty supplements, we felt it was important to investigate the association between the ingredients in these products and the signs we associate with skin ageing, such as wrinkles, loss of elasticity and moisture,” said BNF nutrition science manager Ayela Spiro.

“While there is a body of research on the science of skin ageing, evidence for the benefit of nutraceuticals to skin appearance is currently not strong enough to draw firm conclusions.”