I was somewhat alarmed to learn this month that more than three million Britons cannot get through the day without an alcoholic fix. Alcoholism often goes hand in hand with physical, psychological and emotional problems, and can have a devastating impact on both personal and professional relationships.

However, while psychological strife is a frequent factor in alcoholism, physiology can play its part, too. Craving for alcohol can be induced by an imbalance in the body's chemistry. What is more, correcting this through dietary changes is often very effective in quelling a desire to drink.

The principal energy source in the bloodstream is the sugar glucose, and the body is constantly striving to keep adequate levels of this whooshing around the system. If blood-sugar falls to subnormal levels, alarm bells ring within the body. One common manifestation of this is a craving for something that will replenish fuel rapidly. Some may experience this as a desire to raid the biscuit tin. For others, low blood sugar may translate into an overwhelming urge to hit the bottle.

In practice, keeping blood-sugar levels on an even keel often helps curb a keen desire for alcohol. Regular meals are important, though healthy snacks in between can be helpful. Early evening is a classic danger time for low blood sugar - often the result of the extended fast between an inadequate lunch and an overdue dinner.

A proper lunch, followed by fresh fruit and maybe some nuts in the afternoon is often effective in evaporating a craving for liquid refreshment in the evening. In one study, alcoholics given appropriate nutritional counselling had less craving for alcohol and were more likely to abstain from alcohol.

Another common feature in alcoholism is nutrient deficiency. Heavy drinkers, for instance, tend to lack B vitamins and the minerals magnesium and zinc. There is also some evidence that supplementing with nutrients can reduce alcohol craving and curb intake. Taking a good quality B-complex supplement (supplying at least 25mg of the major B vitamins) along with additional zinc (15-30 mg) and magnesium (300-500 mg) each day may provide a nutritional safety net for those seeking to beat a drinking habit.

Some scientists believe alcohol craving may be related to the mood-boosting molecule prostaglandin E1 (PGE1). In the short term, alcohol appears to increase PGE1 levels. However, long-term drinking appears to deplete the body of PGE1, and this may predispose to depression and alcohol craving.

In the body, PGE1 is made from a fat known as gamma-linolenic acid that is found in evening primrose oil. Taking 1g of evening primrose oil two or three times a day may reduce the craving.

Nutrition news

Many parents will be well aware that fruit is an important component of a child's healthy, balanced diet. Fruit is rich in a range of substances - including vitamins, minerals, fibre and biologically active substances called phytochemicals - many of which may contribute to health and well-being.

However, recent evidence suggests that fruit may have benefits for little ones that extend way beyond childhood. In a study published this month in the Journal of Epidemiology and Community Health , the risk of cancer in a group of elderly individuals was compared with fruit consumption assessed back in the 30s. Compared to those eating the least amount of fruit in childhood, those eating the most were about 40 per cent less likely to succumb to cancer. The risk of death due to cancer was down, too.

The results of this study suggest that encouraging children to eat more fruit may reap health dividends for many decades into the future.

Dear John

Since the New Year, I have cut down on carbohydrates and tried a protein-rich diet. I've lost weight and feel much better. But I've read that too much protein can cause osteoporosis. I'm 51 and am concerned about what this dietary change may be doing to my bones. Should I be worried?
Katherine Horwood

A recent study found that a diet low in carbohydrates but high in proteins led to an increase in the amount of calcium lost from the body in the urine.

This study got a lot of press - though it was, in fact, poorly designed. Plus, other research has not found this apparent link between protein and calcium loss. Another study, for instance, found that women consuming 450g of protein per day lost no more calcium than women consuming just 5g.

Adequate protein intake is very important for bone health. A report in the Journal of Bone and Mineral Research found that elderly women with the highest protein intake had the lowest risk of osteoporosis. Another, in the A merican Journal of Clinical Nutrition, found that higher levels of protein intake were associated with reduced risk of hip fracture.

Your shift to a diet higher in protein, if anything, is likely to help, not harm, your bones in the long term.