The classic Australian meat pie advertisement shows tough men in shorts eating a pie with tomato sauce (similar to ketchup) in the blazing sun.
But could this quintessential Down Under delicacy help to protect Aussie skins from the harmful effects of UV radiation?
Sunlight can cause the formation of free radicals in the skin cells. Free radicals are atoms which exist with an unstable number of electrons in an electron shell. Ultraviolet (UV) radiation can “force” electrons from atoms such as oxygen and create free radicals. Since the electron state of a free radical is so unstable, they are likely to react with anything they touch in the cell – be it a protein or DNA strand. This can lead to temporary damage (such as sunburn) or permanent damage including cataracts – and even to cancers such as melanomas.
Tomatoes contain caretenoids such as lycopene. These are the chemicals which give tomatoes their rich colour. Lycopene is perhaps the most powerful of the anti-oxidants found in any fruit or vegetable.
Anti-oxidants react with oxygen (and other) free radicals to neutralise them before they can harm biological processes. To some extent, the more anti-oxidant molecules in a cell, the more likely a free radical is to hit one of those before hitting a vital part.
Putting caretenoids – especially lycopene – onto the skin has been shown to help prevent and even partially reverse the damage done by exposure to UV light. But it’s not just an external form of sun block – leaving the sauce your pie provides benefits too.
A diet rich in tomatoes has been shown to reduce sunburn and the effects of UV exposure. In fact concentrated cooked tomato (such as tomato paste or sauce) is an even better source of such anti-oxidants than are fresh tomatoes. Forty grams (4 tablespoons) of tomato paste eaten daily has been shown to significantly reduce visible sunburn after only a few weeks.
While not a substitute for sunblock or sun-safe practices, eating a diet rich in tomatoes could thus provide some level of continuous protection. Indeed, it is likely that increasing tomato consumption in your diet may help protect not only against sunburn, but the visible signs of aging, cataracts and skin cancer.
Perhaps in the “sunburnt country” of Australia, it is no coincidence that tomato sauce became the condiment of choice.
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