Alcohol consumption has its positive and negative effects. Alcohol, when consumed in moderation, has many benefits. It seems to be good for the cardiovascular system and circulatory system, and protects against type II diabetes and gallstones. However, when consumed excessively and at the wrong time, alcohol has its fair share of negative effects. Therefore, it is important that alcohol be consumed responsibly.

Alcohol, when consumed moderately and responsibly, can be a part of a healthy lifestyle.

The chemical name of alcoholic beverages is ethanol. The percentage of alcohol in beer is around 5%, for wine is around 12% and for spirits, approximately 40%. A glass of beer (25cl), a glass of wine (12.5l) and a shot of spirit (3.5cl) would contain approximately the same amount of alcohol.

Alcohol contains little protein, fat or other nutrients. In general, beer contains sugar and carbohydrates, some B vitamins, micronutrients and minerals.

The following facts were adapted from the Australian Department of Health and Aging, Australian Alcohol Guidelines Fact Sheets, as well as Beer Consumption & Health – Review of Medical Research by Heineken International.

A1. Heart Diseases

Overwhelming number of screenings have proven conclusively that moderate consumption of alcohol beverages has a protective effect with respect to cardiovascular diseases, regardless of gender. The mechanism underlying this effect is largely due to the increase in HDL cholesterol, commonly known as the good type of cholesterol, in the blood. It must be noted that this is very much dependent on the pattern and level of drinking where the protective effect comes from a regular drinking pattern, of a low to moderate amount (of less than 1 standard drink per day for women and 1 to 2 for men) of alcohol.

This protective effect appears to be due to the alcohol itself and not to specific components of the drink. Therefore there is no distinction between wine or beer or spirits.

It has also been shown that high consumption increases blood pressure.

A2. Strokes

Moderate consumption may offer some protection against ischaemic stroke (sudden blockage of blood vessels to the brain) but not haemorrhagic stroke (due to the rupture of a blood vessel in the brain).

Heavy consumption increases the risk for both types of strokes.

A3. Type II Diabetes

Type II diabetes, the most common form, occurs when the body has decreased sensitivity towards insulin. Evidences have shown that moderate consumption can reduce the risk considerably.

A4. Other conditions

There may be other health benefits such as protection against gallstone. However, more studies are needed in these areas.

B1. Liver Diseases

It is an established fact that chronic alcohol abuse causes liver diseases such as fatty liver (steatosis), alcoholic hepatitis (inflammation of the liver) and cirrhosis of the liver (scarring of the liver). It should be noted that the quantity and duration are both determining factors for the development of liver cirrhosis, possibly besides genetic factors, immune responses and perhaps nutrition.

According to the American Liver Foundation, many victims of liver diseases are not alcoholic. In fact, alcohol is only one of many causes of liver diseases, and the risks depend on the quantity drunk and duration. Cirrhosis of the liver is found among alcoholics 10 to 25 percent of the time, after a long duration of excessive drinking.

B2. Hangover

A night of heavy drinking may cause a hangover – a feeling of malaise, headache, nausea, etc.

B3. Cancer

Tests suggest that alcohol does not directly cause cancer but can stimulate the occurrence of cancer in the presence of other carcinogenic substance. For example, there appears to be a slight increase of breast cancer risk among women.

B4. Diabetes

There are basically two types of diabetes – Type I and II. Type I diabetes is a disease in which the body does not produce any insulin while Type II, which accounts for 90 to 95 percent of all diabetes occurs when the body has decreased sensitivity towards insulin.

For Type I, heavy drinking may lead to serious deregulation of glucose levels in the blood and cause complications such as neurological diseases and high blood pressure.

For Type II, studies have shown that moderate alcohol consumption can actually reduce the risks.

B5. Fetal alcohol syndrome

Heavy chronic alcohol abuse by pregnant women can lead to Fetal Alcohol Syndrome (FAS), characterised by three symptoms – severely retarded growth, deviations in the central nervous system and specific facial deviations.

Most of the time, drinking does not cause any problems and is not detrimental to health. It is only drinking too much or at the wrong time that can be harmful. The key thing is to know where the benefits end and the risks begin.

C1. General Drinking Guidelines

The blood alcohol concentration ie., the concentration of alcohol in your body, depends on several factors such as gender, volume drunk, duration; whether or not the person has eaten; and a person’s size and weight.

A healthy liver takes about 1½ hrs to break down and remove 10 grams of alcohol.

C2. What is a unit of alcohol and what constitutes moderate alcohol consumption?

According to the UK Department of Health, a unit of alcohol is 10ml of pure alcohol. It is advised that men should not regularly drink more than 3 – 4 units of alcohol per day, while women should not drink more than 2 – 3 units of alcohol per day.

The Harvard School of Public Health defines moderate drinking as the point where the health benefits of alcohol clearly outweighs the risks. The WHO Guide to Mental Health and Neurological Health in Primary Care mentions up to 3-unit drinks for men per day and 2 for women, with two alcohol-free days per week.

The chart below shows the number of units of alcohol in common drinks:

3.0 Individual Differences

These are only guidelines where individual differences must be taken into account.

4.0 Who should not drink?