Dr Nicholas Perricone, the American doyen of dermatology, antiageing specialist to the stars and author of a new book, 7 Secrets to Beauty, Health and Longevity, is arriving in London today to reveal his top tips for holding back the years, many of which revolve around good nutrition.

For our skin his advice is simple: instead of taking cocktails of supplements, just stay away from sugary, refined carbohydrates such as muffins and biscuits, cakes, puddings, sweets and sugar-rich drinks. In other words: the GI diet is both good for your weight and vital for your skin.

These “high-GI foods” are rapidly digested, quickly raising levels of sugar in our blood, which triggers large amounts of the hormone insulin to be released to help to return the sugar level to normal. According to Dr Perricone, controlling blood sugar is the single most important antiageing step we can take to help to age beautifully, prevent wrinkling and preserve lean muscle mass.

“When we eat foods that cause a sharp spike in blood sugar, it results in elevated levels of insulin, causing an inflammatory response,” he explains. This in turn results in the damage or “glycation” of collagen, the protein in the skin that helps to make it bouncy and youthful. Any destruction to collagen lays the foundation for wrinkles and loss of elasticity.

He compares the skin to a rubber band. When young, it will snap back into place if stretched. With damage to collagen caused by glycation, the skin and its underlying structure lose the ability to snap back into place.

Dr George Roman, of the Aesthetic Medical Centre in London and a specialist in nutrition and antiageing, backs up this theory: “It is true that excess sugar and insulin in the blood causes glycation where a sugar and a protein react together. You see it in the eyes of people with diabetes. The sugar and insulin damage the eye proteins in the lens, causing cataracts. When glycation occurs in collagen it damages the collagen itself as well as collagen-producing cells. The end result is to increase the normal process of skin ageing by reducing flexibility.”

So what can be done? Beans and lentils get the Perricone thumbs up. Not usually considered “beauty food”, they can exert a stabilising influence on blood sugar and insulin levels. They include red kidney, borlotti, cannellini, haricot (baked) and butter beans, peas and red and brown lentils.

Apples, pears and oats are also good since their soluble fibre is believed to be particularly helpful in stabilising blood sugar. Other lower-GI choices include sugar-free muesli; pears, peaches and berries as snacks; tortilla wraps and pitta at lunchtime and al dente pasta or new boiled potatoes for dinner.

If such simple, low-tech beauty-boosting dietary advice seems surprising, you may also raise an eyebrow at being urged to stop nibbling exclusively on staples such as salad leaves and mung beans. Instead, Perricone wants us to get stuck in to a decent 8oz sirloin steak. He explains that protein is of major importance in stimulating cells to repair themselves. Since we cannot store protein in our body, a vital part of his antiageing plan is that we eat enough high-quality protein every day.

The advice to eat adequate protein makes sense, given that collagen and elastin consist predominantly of protein and about 95 per cent of the skin’s second layer, the dermis, is made up of collagen and 3 per cent is elastin.

Although our National Food Survey of Adults in Britain shows that on average we are eating the recommended daily amounts of 54g (1.9oz) of protein for women (and 62–72g daily for men), the reality is that for many women, when dieting to control body weight, protein intake nosedives.

To meet a woman’s daily goal, for example, you need to tuck away two scrambled eggs for breakfast, a decent sized piece of salmon in a salad for lunch and a good 220g serving of chilli con carne (that is, before any carbohydrate it is served with) for dinner. If you were to have the more likely dieter’s choice of, say, bran flakes and milk for breakfast, vegetable soup and a roll for lunch and a piece of grilled chicken for dinner, your protein would be 44g — 10g below the recommended intake.

Such a protein deficit will, says Dr Perricone, lead to a visibly accelerated ageing process because the body is forced to feed on itself. His really bad news is that this lack of protein is first noticeable in the face.

Once you have your carbs and protein intake established, then the least surprising of Dr Perricone’s tips swings into action; to stock your “AntiAgeing Kitchen” with plenty of vegetables and fruit. Few interested in skin care would quarrel with this notion. Vitamin C remains the skin’s most important antioxidant vitamin, because of its attempts to deactivate sun-induced free radicals in the skin that, left unattended, trigger sun damage. Along with these, a daily diet of fruits such as oranges and grape-fruit (try to eat the antioxidant-rich white pith) and a wide variety of brightly coloured berries, again all good for vitamin C and antioxidant flavonoids, is sound dietary advice with potential skin nourishing benefits.

Put it all together and a typical Perricone antiageing menu consists of almond-encrusted wild salmon fillets on a bed of wilted greens served with parsley and saffron-scented oat pilaf and a pudding of extra-dark organic chocolate with blueberries. This may just be the fantastically tasty elixir of youth for which we have been searching.

The Aestethic Medical Clinical: 020 7323 2123

Do you have a nutritional topic that you would like Amanda to cover on this page? E-mail amanda.ursell@thetimes.co.uk Write to: times2, 1 Pennington Street, London E98 1TT. Amanda cannot enter into personal correspondence.

Explore Health

• Expert Advice

• Health Features

• Mental Health

• Alternative Medicine

• Child Health

• Health Club