Professor Brian Ratcliffe, the program leader of nutrition and dietetics at the Robert Gordon University in Aberdeen, Scotland, told the Festival many food supplements were ineffective for the majority of people and overuse of vitamin C for example, could lead to stomach problems.
Vitamin A was singled out as easily exceeding recommended levels if a consumer was to combine multivitamin use with a fish oil supplement. Potential side effects included headaches and nausea, osteoporosis, and eye and liver damage.
His statements have been picked up in the UK mainstream press in the past couple of days. Industry associations were unavailable for comment at the time of publication.
Professor Ratcliffe, who is an adviser to the UK Food Standards Agency (FSA), was also unavailable for comment.
The National Association of Health Stores issued a statement backing supplement use, as a way of compensating for nutrient-poor diets: “Evidence amassed by the Food Standards Agency tells us that the concept of the healthy, balanced diet still eludes the overwhelming majority of the British public.”
“And, of course, if you are ill, smoke, drink alcohol or exposed to environmental toxins such as traffic fumes your body benefits from a higher intake of vitamins and minerals and of course, if you are eating less than a certain number of calories such as when you are dieting, it is more difficult to get the nutrients you need from food.”
Professor Ratcliffe notes taking food supplements can be dangerous for those who may be taking pharmaceuticals.
UK supplement sales falling
His comments come at a time when vitamin sales are falling in the UK, at least according to analyst, Mintel, which predicts sales will slide from €155m in 2004 to below €100m by 2014 – a near 50 per cent decline.
Over the same 2004-2014 period, total sales of food supplements would grow from €252m to €382m. Mintel put 2008 sales at €294m.
The analyst speculated this was due to consumers taking more specialist supplements such as omega-3s and glucosamine.
“Vitamins and supplements are generally regarded as a non-essential spend,” Mintel said in a May report. “People are finding alternative ways to fight fatigue or maintain nutrition through food and drink.”
“High levels of NPD targeting specific lifestage needs (notably childhood, menstruation, pregnancy and the menopause) have served to focus people’s minds on trading up to dietary supplement formulations that will better meet their needs.”
Functional foods are also taking patronage from the food supplements sector, as they rose in popularity.
However, fellow analyst Euromonitor puts the UK food supplements market at €938.1m in 2008 compared to €911.2m in 2007.
"People who take multivitamin supplements are probably just wasting their money and boosting the profits of vitamin companies,” Ratcliffe said at the annual Science Festival.
"It's a whole new area. We haven't had a significant proportion of the population taking all these supplements before. They should certainly speak to a doctor or dietician or nutritionist. I think they'd be better off investing time in trying to choose healthy items for their diet rather than thinking you can bolt on that safety margin by just taking a supplement."
A study published in the June edition of the American Journal of Clinical Nutrition found the cells of multivitamin users had a younger biological age than those who didn't use supplements.