Food manufacturers are set to have better ammunition in their quest to get health claims approved by the European Commission ­after a three-year, £4m research initiative to clarify the links between food and health was announced.

The EC brought in new rules to regulate the health claims that can be made about foods in 2007 and many manufacturers have since failed to get claims approved because their ­scientific evidence was deemed unsatisfactory.

The new initative will see scientists work on nine ­research projects, jointly funded by research councils BBSRC, EPSRC and MRC and 13 food and drink companies. They will explore issues including: how digestive health can be promoted through functional foods; how changes in cow feed may produce dairy products with lower saturated fat content; and how reduced-fat foods could be made more appealing to consumers.

Professor Caroline Wheeler-Jones of the Royal Veterinary College, who is leading a Unilever-backed research project into the ­effects on the body of ­omega-3 polyunsaturated fatty acids found in fish and plant oils, said that ­although there were epidemiological studies suggesting omega-3s were beneficial to health, scientists did not yet understand exactly why.

"We will be looking to add some really sound scientific evidence that omega-3s are good for you," she said, adding that better ­understanding would help companies market their foods more effectively.

Companies backing the research include Marks & Spencer, Coca-Cola, Danone, Kraft and Nestlé.