Scientists have discovered that lycopene, which gives tomatoes their bright red colour, can turn sperm into super-sperm.
Researchers at the University of Portsmouth studied the effect of lycopene in the diet on a random group of six healthy men, with an average age of 42. The men were asked to consume a 400g tin of Heinz cream of tomato soup every day for two weeks.
The researchers, from the university''s biomedical science department, said that during the two weeks, levels of lycopene in the men''s semen rose between seven and 12 per cent, which was ''significant''.
They added that further studies should be carried out to discover whether the same boost would be seen in infertile men. The results, published in the British Journal of Urology, said that infertile men have lower levels of lycopene in their sperm. The study suggests that higher levels of lycopene are associated with increased fertility.
It is not known what part lycopene actually plays in fertility, although it has been suggested that the antioxidant may mop up harmful free radicals in the body which can affect fertility.
Tomato products have been thought for some time to have beneficial health properties because of their high concentration of lycopene, but this is the first time they have been shown to boost fertility.
Other fruits and vegetables that are high in lycopene include watermelon, pink grapefruit, pink guava, papaya and rosehip. Lycopene has previously been identified as a potential aid in conditions ranging from exercise-induced asthma to prostate cancer. However, earlier this month, the US Food and Drug Administration said it has found almost no evidence that lycopene has any effect on cancer prevention. A review, published in the Journal of the National Cancer Institute, examined 81 studies of lycopene and concluded that none produced any credible evidence to support a relationship between consumption of the antioxidant and the risk of developing cancer.
About 2.6 million men in the United Kingdom have a low sperm count and doctors have suggested a healthier lifestyle can increase the chances of conceiving. Nigel Dickie, a spokesman for Heinz said: "It''s good to know that our tomato soup could give guys extra oomph."