The results of the current study could help influence companies on how health claims are worded in order to gain the biggest consumer appeal.

Klaus Grunert, professor of marketing at Aarhus School of Business at the University of Aarhus, Denmark, said there had only been a "little amount" of research into what makes a health claim convincing.

Health claims are an important subject to the industry, as new regulations are in motion, that will mean claims have to be backed up by science before they can be made. The European Food Safety Authority will be in charge of evaluating the science to see whether it backs up a claim before a final list of approved wording is agreed in 2010.

Price came out as the most important factor when it came to deciding between different products.

Familiar

Grunert, who is also the director of Center for Research on Customer Relations in the Food Sector, said the study recruited 1,000 people each from Denmark, Finland, Norway and Sweden between the age of 15 and 75.

He concluded that one of the least important parts of a health claims is the use of modifying words, such as "may" or "could."

Researchers framed a series of claims, ranging from just what the ingredient is, to its function and desired health effect.

How the question was framed and how it was qualified were also examined

Grunert looked at posing a range of these questions for the popular ingredient omega-3 and for lesser known bioactive peptides.

They tested these products against claims for cardiovascular health, dementia and weight.

In summary, he said the familiarity of the ingredient is very important, as more people chose omega-3 over bioactive peptides because they had heard of it, more so than because of the claim being made. 

"Many people have heard of  omega-3 and this has a very big effect on how convincing a claim is," he said.

Price

But consumer knowledge of an ingredient is not as important as price when it comes to deciding which one to buy. More consumers in the test chose a cheaper loaf of bread with no added ingredient, as opposed to a more expensive loaf with omega-3.

The group also set out consumer tests, lining up four breads at different prices and with different ingredients and claims.

Claims were also made on a yoghurt product and for pork chops.

"People made their choices mostly because of the price of the product. Having said that, we found there were two groups. One group was affected just by the price, the other was affected mainly by the price but also by the ingredient."

This latter group, however, was not influenced as much by the claim type or the health benefit of the ingredient.

A similar result was found for the yoghurt. But a health claim for a pork chop put people off. He said this was because consumers considered pork chops to be less processed than a yoghurt or bread. A health claim on this sort of product implies it had been interfered with in some way, Grunert added.

Grunert presented the findings at the Food in Action conference in Brussels.