THE trend for healthier eating has led to an increase of more than 300% in the number of laboratory experiments conducted on animals for food additives, sweeteners and health supplements over the past year.

Home Office figures showed an increase from 862 to 4,038 experiments from 2005 to 2006.

The disclosure will ignite an ethical debate about the way animals have become victims of the fad for health foods. Animal welfare groups said many of the tests are unnecessary or could be performed on humans.

The experiments often involve using painful procedures and artificially induced injuries to research the effects of food.

In a test at Glasgow University, rodents were fed raspberry juice and then killed to see where the juice had gone in their kidneys, liver and brains. At Hammersmith hospital, west London, rats were force-fed fish supplements, while at Glasgow Caledonian University they had the food supplement ginkgo biloba injected into their paws.

At Robert Gordon University, Aberdeen, rats were fed a diet containing 20% raw, lightly cooked or fully cooked cabbage for two weeks. The animals were killed to examine the effects of the diet on their liver and colon. The researchers had already carried out a human study on the effects on the gut of eating cooked cabbage.

Other experiments included feeding a health drink to rats to see whether they ate more chocolate, vanilla or asparagus flavour.

Although most food tests are performed on rodents, rabbits, guinea pigs and dogs are also used.

In experiments in the United States, Teavigo, a purified green tea extract, available by mail order in Britain, was rubbed onto the shaved backs of guinea pigs and rabbits and put in the eyes of live rabbits.

Dogs force-fed huge doses of Teavigo - which is marketed as “green tea in its purest form” and a choice for “health-conscious consumers” - died or had to be put down.

Gerhard Gans, director of regulatory affairs at DSM Nutritional Products, which produces Teavigo, said: “In some cases it is necessary to use dogs, they are in some aspects more similar to humans than rats . . . where it is possible to use alternative methods validated by the authorities we will use [them].”

Home Office statistics show that in addition to the experiments for additives there was a 30% increase to 7,477 tests on animals for other foods from 2005-6.

A spokesman said the tests on food are needed to meet regulatory requirements.

Michelle Thew, chief executive of the British Union for the Abolition of Vivisection, said: “The rise in testing of food on animals in the race to find the next lucrative ‘super-food’ is a hidden scandal. People are unaware of the animal suffering behind the headlines.”

Additional reporting: Roger Waite

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