Tomatoes are a rich source of the antioxidant nutrient, lycopene. Studies have shown that lycopene can help protect body cells from oxidative damage in the same way that antioxidants in food processing prevent fats from becoming rancid.

A review in the European Journal of Clinical Nutrition collated studies on tomato products and health. Unlike other fruits and vegetables, tomatoes demonstrate higher levels of antioxidants when they are processed. This means that tomato products, such as tomato paste, sauce, ketchup and puree contain more lycopene than fresh tomatoes.

The authors found that adding tomato products to the diet helped protect body cells from oxidative damage in both healthy patients and those with type 2 diabetes. Consumption of tomato products also seemed to lower the risk of certain cancers. Tomato products which contained some dietary fat offered the most powerful combination, probably because fat helps to increase the absorption of lycopene into the blood.

Laboratory tests have shown that lycopene from tomatoes can protect the protein, fats and DNA inside our cells from damage. Anti-cancer effects were particularly seen with prostate cells and, indeed, there is evidence to suggest that a diet rich in tomato products seems to be protective against prostate cancer.

The review concluded that processed tomato products provide significant health benefits. While most of the effect is likely to be due to lycopene, other naturally-occurring nutrients could be involved. More research is needed to understand these further.

For more information see:
Basu A & Imrham V (2007). Tomatoes versus lycopene in oxidative stress and carcinogenesis: conclusions from clinical trials. European Journal of Clinical Nutrition, vol 61: pp 295-303.

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