Alcohol and your health

Written by Catherine Saxelby on Monday, 05 October 2009.
Tagged: alcohol, healthy lifestyle

Alcohol and your health

Alcoholic drinks have been drunk for thousands of years and, in moderate quantities, provide pleasure and help people relax both mentally and socially. Although excess alcohol is detrimental to health, there is evidence that modest intake (one or two drinks a day) can actually be beneficial. Studies show that people who drink moderately are less likely to suffer heart attacks, and live longer than total abstainers or those who consume three or more drinks a day. Alcohol appears to work by thinning the blood and keeping arteries elastic and able to ‘flex in and out' under pressure.

This good news on alcohol should not be taken as an excuse to over imbibe. Too much wine, beer or spirits inflames the lining of the stomach, intestine and pancreas and interferes with the metabolism of the B vitamins, as wells as zinc and magnesium. It can lead to cirrhosis of the liver (although not all alcoholics develop this) and can produce Wernicke-Korsakoff's syndrome, a disturbance in mental functioning caused by lack of thiamin (vitamin B1). Alcohol-related thiamin deficiency is a major health problem in Australia and Wernicke-Korsakoff's syndrome is more common here than in other, similar countries.

Alcohol piles on the weight

Alcohol should be strictly limited by dieters as it is a concentrated source of kilojoules. At 29 kilojoules per gram, pure alcohol has almost twice that of carbohydrate or protein. Alcohol can be used in cooking, however, as the heat evaporates much of it, leaving an enhanced flavour with few fattening kilojoules.

Don't drink and drive

Drinking and driving are a most dangerous combination; statistics show that alcohol is involved in about half the serious car accidents in Australia. It takes the body about one hour to eliminate the alcohol from a single glass of wine or spirits, and about 12 hours to eliminate half a bottle of spirits (hence the reports of people having too-high blood alcohol levels the morning after a heavy party).

Alcohol absorbed fast

Alcohol (ethanol) is absorbed directly from the stomach and intestine, and so enters the bloodstream within minutes of drinking - much faster than does food. The rate of alcohol absorption varies from person to person, depending on individual sensitivity to alcohol, frequency of intake, type and concentration of drank, genetic background and body weight. The lighter your body, the less body fluids you carry to dilute the alcohol, the greater its effect - hence women are usually affected more quickly than men.

Having something to eat reduces the rate of absorption, especially if the food is high in fat or protein (like cheese, nuts, or that old pre-drink favorite, milk). Carbonation such as the tiny bubbles in champagne, on the other hand, increase the rate of absorption of alcohol.

Alcohol and your liver

  • Alcohol is metabolised mainly by the liver, where it is converted to acetaldehyde and enters the body's biochemical pathways. A small proportion of alcohol is also removed in the kidneys, sweat and breath (which explains why alcohol can be detected by breathalysers).
  • If you plan to drink and drive, count your drinks carefully. Three standard drinks over an hour will put your blood alcohol level up 0.05% (g per 100ml of blood). After that first hour, just one drink per hour will keep it at 0.05%, the maximum legal limit in most States.
  • If you can not count the number of drinks you've had, do not drive! Neither strong coffee, vigorous exercise nor cold showers speed the rate of alcohol breakdown in the body, but fructose (fruit sugar) has been found to do so in test labs and is often sold with claims that it can help you sober up. Unfortunately the amounts needed to work are quite large and would make you feel unwell so don't believe what you read about fructose.

Units of alcohol - standard drinks

Standard bar glasses of drinks provide practically the same quantity of alcohol, despite differences in their alcohol content by volume. A small nip of rum contains 10g of alcohol, as does a glass of wine, a glass of champagne or a glass of port. This is important, as advice on drinking and driving is always given in terms of the number of ‘standard drinks' or ‘units', yet a recent survey discovered that people's perceptions were considerably in excess of the standards! The following standard drinks all provide approximately 10g of alcohol.

Beer regular 250ml (2/3 can or 1 middie)
Beer low alcohol 375ml can or bottle
Breezer/Cruiser 300ml bottle
Wine 100ml (1 small wine glass)
Sherry, port 60ml (1 sherry glass)
Spirits (gin, vodka, rum)  30ml (1 nip)
Liqueurs 30ml (1 nip) 

How much is too much?

The latest medical advice is that women should not drink more than one standard drink a day and men should not drink more than two. More than four drinks each day is potentially hazardous to health, bringing with it a high risk of metal and physical damage. Pregnant women should not drink at all, especially during the first three months of pregnancy, as there is a risk of birth defects.

Aim for:

  • No more than 2 glasses a day (for men)
  • No more than 1 glass a day (for women)
  • With some days free of alcohol

Alcohol's many and varied side effects 

1. Unhappy hangovers

Many people suffer ill-effects from excess alcohol in the form of a hangover - a pounding headache, a drier-than-dry mouth, loss of balance, nausea and fatigue. Hangovers have three causes:

  1. dehydration
  2. alcohol's interference with the body's chemistry
  3. alcohol-associated substances (called congeners) such as tannins, volatile acids, methanol and histamines.

Researchers believe that these congeners actually cause more headaches than the alcohol itself. Brandy, sherry and red wine (especially cheaper brands) have been shown to produce the most distressing head aches, followed by rum, whisky, beer, white wine and gin. The least effect is produced by vodka. Mixing different types of drinks can also produce hangovers.

2. Diuretic action, dehydration and B vitamins

Alcohol is a diuretic, forcing the kidneys to produce more urine. If you have overindulged, one way of avoiding a hangover is to drink one or two large glasses of water before going to bed, as this replenishes body fluids and prevents dehydration. B vitamin pill may help, as alcohol prevents the proper absorption of B vitamins and depletes them from the body for its own metabolism. From time to time fortification of beer and wine with thiamin (vitamin B1) has been suggested as a means of avoiding the problems of alcohol -induced thiamin deficiency in heavy drinkers.

3. Headaches and allergy reactions

Headaches, wheeziness and other reactions do occur. Some people find that red wine produces more headaches than white because of its higher content of tannins and histamines. Asthma sufferers may find themselves unknowingly affected by white wines, which generally have more sulphur dioxide (additive number 220), a compound used since ancient times to delay oxidation. Wheeziness, sniffles or sinus problems can also be traced back to the sulphur.

Sufferers of yeast allergies may react to wine or beer. And there is a long list of medications whose actions are antagonised or increased by alcohol.

4. Interference with medications & driving

Anyone taking sedative, tranquillisers, anti-depressants, certain painkillers and flu tablets should check with a doctor or pharmacist before drinking. Often the medication pack carries a warning and it is essential to heed it, especially if driving or operating machinery.

Alcohol and sex

While alcohol in moderate amounts acts as a social lubricant, heavy drinkers often discover that too much has an unhappy effect on sexual drive and function - a fact well known to most men. Alcohol lowers the level of the male sex hormone, causing loss of libido, decreased sperm production and occasionally impotence. It can increase the excretion of the mineral zinc, which is concentrated in semen and the prostate gland and is required for full maturation of the sexual organs in adolescents.

Nutritional value?

Alcoholic drinks score low in nutrition, despite the fact that their raw material like grapes (to make wine) or malted grains (beer) are quite nutritious. Thiamin, for example, is present in grains but in the manufacture of beer is destroyed, or concentrated in the yeast and lost from the beer when it is clarified and the sediment removed. Varying amounts of minerals such as potassium and iron are present - red wines and dark beers can carry substantial amounts of iron - but little else apart from sugars and alcohol.

Alcohol content of common drinks

Drink% alcohol by volume*

Beer, extra light

less than 1

Beer, low alcohol

2 - 3

Beer, regular & low carb

4 - 5

Alcopops/mixer drinks (Breezer, Cruiser)

4 - 5

Cider

4 - 5

Wine

10 - 13

Champagne 

12

Vermouth, Marshal, Madeira

16 - 18

Sherry 

16 - 18

Port, Muscat

18 - 20

Spirits (brandy, rum, whisky, gin, vodka, bourbon)

32 - 40

Liqueurs (Grand Marnier, Cointreau, Creme de Menthe, Drambuie, Kahlua)

30 - 40

* Alcoholic drinks must state on the label the percentage of alcohol, the number of standard drinks, and the presence of any preservatives or colours.

Catherine Saxelby

About the Author

Catherine Saxelby knows nutrition! She is an accredited nutritionist, food commentator, blogger and award-winning author. Her latest book Catherine Saxelby's Food and Nutrition Companion answers all those tricky questions on healthy eating, diets and supplements. It draws together a lifetime of advice and gives you all you need to know to eat right! It's a complete A to Z. A handy desk go-to reference.