Dr Wynnie Chan investigates the nation's drinking habits and whether or not we're all over our limit

We're all aware that booze isn't the healthiest of substances, but how much is really too much? A recent report by the Royal College of Physicians in London showed an increase in chronic liver disease in the UK due to the fact that 15% of men and 27% of women are drinking more than their recommended weekly amounts. Are you putting yourself at risk by guzzling too much of your favourite tipple?

Current alcohol recommendations in the UK are up to 4 units a day for men and up to 3 units per day for women, regardless of body weight. One unit contains 8g or 10ml of alcohol and is equivalent to:

• 1/2 pint ordinary beer, lager or cider
  
• 1 single measure of spirits
  
• 1 small glass of wine
  
• 1 measure of fortified wine, e.g. port or whisky

According to experts, anyone who regularly drinks more than 3 or 4 units a day is placing an increased risk to her health. In last year's report entitled Health in England 1998: Investigating the links between social inequalities and health published by the Stationary Office, it was estimated that 17% of women in Britain reported drinking more than 14 units per week, and 30% of men drank more than 21 units of alcohol per week.

So how does alcohol affect your body? Depending on the individual, a moderate amount of alcohol (30g of alcohol a day, or the equivalent of 3-4 glasses of wine) produces a range of negative short-term effects on the body, including an increase in heart rate, heart palpitations, an increase in skin temperature, muscle weakness and facial flushing. Alcohol also promotes water loss from the kidneys, which can lead to dehydration, particularly amongst people who drink spirits (which have a higher concentration of alcohol) without consuming extra water.

Mental function is, of course, also inhibited. According to The Royal College of Physicians' study, men and women are affected in the following ways: two glasses of wine increases the likelihood of having a driving accident, half a bottle of wine increases cheerfulness and loosens inhibitions and one litre of wine causes a slurring of speech and a tendency to be quarrelsome. These effects persist until all the alcohol has been metabolised by the liver, or processed and eliminated from the body. A general rule of thumb is that it takes around one hour to metabolise one unit of alcohol, but this rate differs slightly for everyone.

Moderate alcohol consumption has in fact been shown to have a protective effect against coronary heart disease amongst men and women over 50 and post-menopausal women. However, studies have also shown that this amount can increase the concentration of steroid hormones in pre-menopausal women, which may increase their risk of breast cancer.

Long-term, excessive alcohol consumption can be harmful because its toxicity can make our metabolic processes irregular or even damage them.

High alcohol consumption is linked to raised blood pressure, cerebrovascular disease such as strokes and coronary heart disease, liver disease such as pancreatitis, and some cancers such as oesophageal cancer.

Alcoholic women have also reported a decrease in libido, irregular menstrual cycles and, in severe cases, becoming sterile. Studies have shown a link between a mother's excessive alcohol intake during pregnancy (i.e. over 10 units per day), and foetal alcohol syndrome, which results in incomplete growth and formation of the foetus, as well as a number of congenital abnormalities such as those of the heart and joints.

Generally speaking, alcohol tends to affect women more than men. This is because women's livers are smaller and we can't metabolise alcohol as quickly as men so it stays in our system longer.

Finally, it is important to remember that although alcohol contains no fat, it is high in calories:

• 1 glass of wine = 83 calories
• 1 pint of beer = 165 calories
• 1 standard measure of whisky = 51 calories

It's easy for these calories to add up quickly because you're consuming a liquid, so if you're watching your waistline it's best to moderate your alcohol intake.

Experts recommend keeping your alcohol levels within the daily benchmark of 2-3 units a day if you're a woman and 3-4 units a day if you're a man.

If you are worried that cutting back on drinking will affect your social life, here are some tips for how to minimise your alcohol consumption:

• Alternate an alcoholic drink with a non-alcoholic one
• Drink water throughout the night to stay hydrated
• Sip your drink slowly so it lasts longer
• Try to eat before you go drinking since it will help reduce the amount of alcohol absorbed by your body. This should also help prevent bingeing on 'midnight meals', often the result of a night of drinking.

Unfortunately, there is no type of alcohol that is less harmful for you, so the above applies to wine, beer and spirits.