Scientists say tomatoes may provide the best defence to keeping skin looking young and safe from sun damage.
Tests have shown that eating tomato paste could help protect against sunburn and skin ageing caused by sunlight exposure.
The age-defying ingredient is lycopene - the natural pigment that makes tomatoes red - with highest levels found in processed or cooked tomatoes used in ketchup, paste, soup and juice.
In the study, women eating a diet rich in processed tomatoes had increased skin protection, as seen by a reduction in skin redness and less DNA damage from ultraviolet (UV) exposure.
Researchers compared the skin of 20 women, half of whom were given five tablespoons (55g) of standard tomato paste with 10g of olive oil every day for 12 weeks.
The effects on their skin were compared with the remaining volunteers, aged between 21 and 47, eating just olive oil for the same length of time.
The volunteers were exposed to UV rays found in sunlight at the beginning and end of the trial.
The researchers found significant improvement in the skin’s ability to protect itself against UV among those eating tomato paste.
Compared with the other women, the tomato-eating group had 33 per cent more protection against sunburn in the form of less redness.
The researchers calculated that protection offered by the tomato paste to be equivalent to a sunscreen with a sun protection factor (SPF) of 1.3.
Skin samples taken from groups before and after trial showed an increase in levels of procollagen, a molecule which gives skin its structure and loss of which leads to skin ageing and lack of elasticity.
There was also less damage to mitochondrial DNA in the skin, which is also linked to skin ageing.
Dermatology scientist Prof Mark Birch-Machin from Newcastle University said the tomato paste eaten was not overly excessive, but the amount that would be consumed from a lot of tomato-based meals.
“Eating tomatoes will not make you invincible in the sun but it may be a useful addition to sun protection along with sunscreen, shade and clothing,” he said.
“The protective effect of eating tomatoes on our mitochondria is important as they are the energy producers in all our body cells including skin. Therefore being kind to our mitochondria is likely to contribute to improved skin health, which in turn may have an anti-ageing effect,” he added.
Prof Birch-Machin will present details of the research at the Royal Society of Medicine in London, Thursday.