But there are dietary counterweights: "Berries have a strong protective effect against free radicals; that is, they've got a lot of antioxidants," says Lauber, referring to substances that interact with and stabilise free radicals. "And the rule is, the darker, the better."
According to Axt-Gadermann, a glass of elderberry juice has the protective potential of 14 glasses of red grape juice and 55 glasses of apple juice. A small amount of sour berries also covers a person's daily requirement of vitamin C, which improves the elasticity of the skin and promotes digestion.
Spinach, too, has an enormous protective effect, Lauber says. 100 grams of it packs the protective punch of 240 grams of rucola or 1,900 grams of cucumbers. Broccoli is also a highly beneficial food, he says, with an almost medicinal effect like many other green vegetables, which - thanks to their high vitamin-B content - alleviate minor inflammations and thus make for a fresh complexion and healthy skin. And Lauber swears by the beauty aid beloved of fashion models, namely green tea.
The carotenoids in tomatoes and carrots not only delay skin ageing but also protect against the sun, Axt-Gadermann ads. "Most people forget that they're exposed to the sun every day and don't put on sunscreen," she says, adding that regular consumption of tomato and carrot products provide a sun protection factor of four. Eating carrots also results in a fresh-looking complexion.
A healthy diet also includes carbohydrates and fats, "both of which our body needs," says Harald Seitz, a home economist and nutritionist for the consumer information service "aid" in Germany. He points out that whole grain products contain carbohydrates and are, like fruit and vegetables, rich in dietary fibre.
"They promote regular digestion, which is also a prerequisite for beautiful skin," Seitz says. In addition, he recommends eating omega-3 fatty acids, which are found in walnut oil and grapeseed oil.
Proteins have anti-ageing qualities and can also repair minor skin damage, according to Seitz. "Our skin is made up of collagen, which is formed from building blocks of protein," he explains. Collagen is needed for the formation and replacement of body cells.
Seitz says that ideal foods in this regard are sour milk products such as yogurt, whey and buttermilk, which provide plenty of protein but are low in calories.
- Deutsche Presse-Agentur