A Question Of Health: Should I have my colon checked out for cancer. And how can skinny oldies get fatter?

A friend was advised to have a colonoscopy, on the basis that everyone over the age of 50 should have one every three years. As it happens, in his case they found something that required surgery. Equally, this was the case with a friend of his in his early sixties. Is this something one should consider? I am 58, in good health and have a major check-up every two years. I gather that there are risk factors but I don't know what they are and whether they apply to me.

CANCER CONCERN

A friend was advised to have a colonoscopy, on the basis that everyone over the age of 50 should have one every three years. As it happens, in his case they found something that required surgery. Equally, this was the case with a friend of his in his early sixties. Is this something one should consider? I am 58, in good health and have a major check-up every two years. I gather that there are risk factors but I don't know what they are and whether they apply to me.

Cancer of the colon and rectum is one of the commonest cancers. About 20,000 people die from colorectal cancer every year in the UK. Most of these cancers develop very slowly, and if they can be picked up at an early stage the chance of a cure is much greater than if they are diagnosed later. This is the reason why screening for colorectal cancer is worthwhile. About 25 per cent of people over the age of 50 have some sign of non-cancerous polyps in their intestine. Only a few of these will develop into a cancer, but if a polyp is removed, it substantially reduces the risk of a cancer developing. A colonoscopy involves having a flexible tube inserted into the lower bowel. It allows the doctor to see the whole intestine. If any polyps are seen, they can be removed or biopsied. Like all medical interventions, colonoscopies carry a risk of complications, but this risk is small if the procedure is done by an experienced person. Your risk of getting colon cancer is increased if there is a strong family history of the disease. If you have one colonoscopy in your fifties, you can reduce your risk of dying from colon cancer by up to 50 per cent. Whether or not you decide to have a colonoscopy, you should look out for any signs of bowel disease. These include rectal bleeding or a persistent change in your normal bowel pattern, such as the development of diarrhoea or constipation.

MORE WEIGHT, PLEASE

I am a skinny 85-year-old. I have difficulty maintaining my weight and the last thing I need is fat-reduced dairy produce and sugar-reduced baked beans. There must be thousands like me. We are not being catered for.

I hesitate to recommend deep-fried Mars bars in batter, but there are many people, like you, who need high calorie diets to help them put on weight. With a little effort and imagination, you can increase your calorie intake without radically altering your diet. Here are a few suggestions of how to add calories to the foods that you normally eat. Always use full-cream milk. Fat contains 9 calories per gram - it is the most concentrated form of calories available in ordinary food. You can fortify milk further by adding four tablespoons of powdered milk to a pint of fresh milk, so adding valuable calories. When making coffee, sauces and soups, use milk rather than water. You can even stir in a tablespoon or two of cream. Eat plenty of nuts, which are rich in both protein and fat and high in calories. Use plenty of butter, margarine and mayonnaise and spread it thickly on thick slices of bread. Try to fit in extra snacks between meals. Eat plenty of vegetables, but add melted butter or grated cheese.

A PRICE WORTH PAYING?

What do you know about glyconutrients? Several of my friends have been singing the praises of a programme of pills that apparently offers a far more effective alternative to regular vitamin pills. One such programme is produced by an American company called Mannatech. I hesitate because the pills are very expensive and because I do not fully understand the concept. Is it just an expensive fad?

I maintain a healthy scepticism about all commercial products that claim to dramatically improve health. Glyconutrients come into this category. They are a group of pills and potions that contain a variety of sugars. The company that makes them claims that the modern diet is deficient in some of these sugars, and that taking supplements of them will lead to improved health. The theory is that we evolved from hunter gatherers who ate a diet that contained these sugars in the form of roots, nuts, berries and seeds. Our bodies, it is claimed, need these sugars to function well. In fact, a diet containing lots of fresh fruit and veg also has a good dollop of glyconutrients, so it is not clear to me why anyone would rather take pills costing £100 a month when they can achieve the same effect by eating well. The Mannatech website is full of references to scientific articles. Many are published by another little-known organisation, the Fisher Institute for Scientific Research. The medical director of the Fisher Institute, Candace Freeman McDaniel, is the wife of the medical director of Mannatech, HR McDaniel.

HAVE YOUR SAY: READERS WRITE

V M-P from London avoids medicines when treating threadworm:

My children and I have all picked up threadworms in the past, but rather than resort to prescription drugs, we find an alternative approach (as well as careful hygiene) that gets rid of worms is to increase greatly the amount of fresh fruit and veg in your family's diet and add up to one whole garlic bulb to every meal until signs of threadworm have gone.

Please send your questions and suggestions to A Question of Health, 'The Independent', Independent House, 191 Marsh Wall, London E14 9RS; fax 020-7005 2182 or e-mail health@independent.co.uk. Dr Kavalier regrets that he is unable to respond personally to questions