Dr John Briffa: The peel-good factor

For as long as I can remember, the apple has enjoyed iconic status as a symbol of healthy eating. Many of us will have grown up familiar with the apple's fabled ability to keep doctors at bay, and believe there is much goodness to be had by sinking our teeth into a Granny Smith. However, our appetite for apples has waned somewhat of late. Many of us have become seduced by exotic fruits, with the result that the apple is increasingly finding itself left on the shelf.

But despite their somewhat humdrum image, there is much to recommend about apples from a nutritional perspective. Like other fruits, they are rich in health-giving potassium, vitamin C and fibre. Nutritional science has also revealed that apples are particularly rich in a class of compounds known as flavonoids. More and more research suggests that this group of plant compounds has the ability to protect us from a range of conditions. Recent evidence suggests that eating apples can help reduce the risk of chronic diseases such as heart disease, asthma, lung cancer and diabetes.

One of the flavonoids' chief effects in the body is to combat disease-triggering entities known as free radicals. These are destructive rogue molecules that have been identified as powerful trigger factors in the processes that give rise to chronic conditions such as heart disease, cancer, diabetes and asthma. Laboratory studies show that apples pack considerable punch in terms of free radical-quenching ability: one small apple offers the same protective power as a full gram and a half of vitamin C. This ability of flavonoids to combat free radicals offers significant potential to ward off illness and disease.

One specific type of flavonoid found in apples is known as catechin. Studies suggest that men and women with the highest intake of catechins tend to be less likely to succumb to heart disease. Catechins also appear to have an important role in maintaining healthy lung function and protecting against lung disease. Another flavonoid compound found in abundance in apples is quercetin. Studies have shown that high intakes of quercetin, like catechin, are associated with a reduced risk of lung diseases, including lung cancer and asthma.

The flavonoid compounds that appear to be largely responsible for the potent health-giving properties of the apple are mainly found in the skin of the fruit, which means you should eat the apple's peel. Recently, a study published in the American Journal of Clinical Nutrition showed that eating more apples is associated with some protection from cancer (especially lung cancer), asthma, stroke, death due to heart disease and death due to all causes. So, the evidence suggests that munching on this fruit does have the potential to keep the doctor away.

Nutrition news

Selenium is a trace mineral that has long been believed to have cancer-protective properties. Some studies have found that higher selenium intake is associated with a reduced risk of cancer, and one study found that supplementing with selenium cut the risk of dying from cancer by half. New research from the US has shed some light on how this might work. Laboratory studies reported recently in the Proceedings of the National Academy of Sciences have shown that the nutrient activates a gene that has the capacity to suppress the development of cancerous tumours. This, and perhaps other biochemical effects, helps to explain its apparent ability to keep cancer at bay.

Yet while selenium appears to have much to offer in terms of protection from serious disease, it is one of the nutrients that is dwindling in the British diet. Brazil nuts are a very good source of selenium, and are a convenient way to get more of this essential nutrient. For those considering supplementation, 200mcg of selenium per day is the recommended dose.

Dear John

My 12-year-old son is suffering from a knee condition known as Osgood-Schlatter disease. He is a keen rugby player, but has been told he will need to sit out the season. Can you recommend anything that might help?
Mrs A Lorrimer, Buckinghamshire

The muscles at the front of the thigh attach to the shinbone (tibia) via a tendon which runs underneath the kneecap (patella). This tendon inserts into the shin at a point called the tibial tuberosity, which becomes painfully enlarged in Osgood-Schlatter disease. The pain associated with the condition is generally worse during exercise, and the area below the knee is usually tender to the touch.

The disease normally affects boys aged 10-14. It usually clears up of its own accord in six months to a year, though it is advised that the sufferer avoid running-based exercises during this time.

Some years ago, a nutritional physician told me that Osgood-Schlatter disease almost always responds to treatment with vitamin E and selenium, and my experience bears this out. I recommend that your son takes 400IU of vitamin E each day, and 50mcg of selenium three times a day. It is likely he will see real improvement within six weeks.

Thanks to guardian.co.uk who have provided this article. View the original here.