Scientists and researchers have been meeting in Bern to discuss a new nutritional phenomenon called "functional food", which can include anything from yoghurt to pasta to juice.

Supporters of functional food say it has preventative health benefits and can improve people's overall health. However, critics fear that producers are in danger of crossing a fine line between pharmaceuticals and food.

Experts met for a one-day conference to examine the claims and counter-claims made about the controversial products, and to discuss the issue of legislation in this field.

Functional foods are different to regular products in that they generally contain added vitamin or dietary supplements aimed at influencing one or several bodily functions. These include calcium-fortified dairy products and sports drinks.

Makers of functional foods say the products are designed to be eaten as part of a regular, balanced diet by healthy people who want to avoid getting sick.

Sergio Bellucci of the Swiss Science and Technology Council, who chaired the Functional Food Conference, says that while there are no known harmful effects from such foods, it is difficult to determine if they have any real benefits.

He says legislators are faced with a difficult task.

"Is a functional food a normal foodstuff, or is it more or less a pharmaceutical product? This is the big question today."

Bellucci said milk was the best example of this dilemma.

"Is milk a functional food already, because people say it has a preventive effect on osteoporosis, or is it a normal nutritional product?"

Functional food producers also say that lifestyle plays a large role in dietary needs and claim that their products can help fight the effects of stress, fatigue and even air pollution.

Paul Walter, a biochemist from the University of Basel who spoke at the conference, worries that these claims create unrealistic consumer expectations.

"I think any claim should be provable," he told swissinfo, "and not just have an emotional aspect."

He believes it is up to the food industry to send out a clear message to consumers that functional foods should supplement healthy eating habits, rather than replace them.

Besides calling for self regulation within the food industry, Walter also feels that there needs to be stricter legislation when it comes to deciding whether functional foods belong in the pantry or in the pharmacy. However, he says, that is not such an easy task.

"The problem arises when compounds are added to food which do not fall under food legislation, but under drugs. We will have to make a legal effort to control this."

by Anna Nelson

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