The Facts About Alcohol

What is alcohol? 

• Alcoholic drinks consist mainly of flavoured water and ethanol (C 2 H 5 OH).
• Ethanol is the result of the action of yeast on the sugars/starches found in fruits, vegetables and grains.

Producing Alcohol

                                                Yeast

C 6 H 12 O 6      --------------------------------------------> 2 C 2 H 5 OH + 2 CO 2

Glucose (from sugar or starch)                          alcohol (ethanol) + carbon dioxide

One glucose (or other hexose) molecule fermented by yeast results in two alcohol and two carbon dioxide molecules.

• Methanol is another kind of alcohol and is used to make methylated ('meths') and surgical spirits.  It is highly poisonous, not suitable for consumption and can cause blindness, coma or death if misused.
• Alcohol is a mood-altering drug, which depresses the central nervous system and impairs our ability to think, make decisions and to perform tasks. The more someone drinks the greater the depressant effect.

Is alcohol a drug?

• Alcohol is a drug in every sense of the term. 
• Alcohol is a mood-altering drug belonging to the category called 'depressants'.  These act by depressing or slowing down the central nervous system (ie, mind and body).
• As with other drugs, tolerance to the intoxicating effects of alcohol can develop, as can powerful psychological and physical dependence (ie, 'addiction').
• It is possible to overdose and die from drinking too much alcohol.

What are the effects of drinking alcohol?

• Alcohol quickly enters the bloodstream, and is in most areas of the brain and body within 5 - 10 minutes. 
• After 2 'standard drinks'*, a person may feel less inhibited, more relaxed and more talkative.  Their reaction time has also started to slow down. 
• After 4 standard drinks, judgement, self-control and co-ordination may be affected.  Speech may be slurred, and behaviour may become impulsive or aggressive.
• After 6 standard drinks, a person may stagger, have double vision and suffer some memory loss.
• After 10 standard drinks, the possibility of passing out, falling in to a coma, or even death increase.

• This is why a person admitted to hospital for suspected alcohol poisoning may have their stomach 'pumped' (contents emptied).

*1 'standard drink' = half pint beer = glass wine = pub measure of spirits

Why do people react differently to alcohol?

Some people seem to have pleasurable reactions to alcohol, while others become upset, anxious or aggressive.  In addition, individual drinkers can experience the range of effects from alcohol on separate drinking occasions - or even all on the one occasion.  There are a number of factors:

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Gender

• Women tend to feel the intoxicating effects of alcohol more quickly than men: 

• A woman's body contains less fluid and more fat than that of a man.  Therefore alcohol will be more concentrated in her system;
• Women often weigh less, therefore have less body tissue with which to absorb alcohol;
• Women may also have less of an enzyme needed to metabolise alcohol (alcohol dehydrogenase).
• The weekly low-risk drinking limits reflect this gender difference.  It is believed that women can consume up to 14 standard drinks a week with little risk to their health, while men may consume up to 21. 

Tolerance

• Regular drinking creates a level of tolerance to the intoxicating effects of alcohol. 

• However, the person's blood-alcohol concentration (BAC) will be the same as an equivalent person drinking the same amount.  This means the health risks are also equivalent.

• High tolerance can be a warning sign of a developing or established drink problem.
• Reverse tolerance occurs when liver damage has been caused by prolonged heavy drinking, or other unrelated conditions.  Intoxication is reached very quickly as the liver can not metabolise alcohol at the normal rate.

Size and weight

• A large person has more bodily fluids and body tissue with which to absorb alcohol.  Therefore alcohol may be less concentrated in their system. 

• This is an additional factor going against younger people who have not yet reached physical maturity.

Health

• If a person is ill, run down or tired, the central nervous system is under stress.  Having to cope with alcohol creates further stress, and can result in feeling the depressant effects of alcohol more quickly.
• The use of alcohol is contra-indicated by many medications. 

Mood, expectations

• As a depressant drug, alcohol can exaggerate mood.  Those drinking because they feel upset or under stress may find they feel worse.  Tearfulness, aggression and feelings of depression are not uncommon effects from alcohol.
• An expectation of a certain effect can also influence the actual experience of the drinker.

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Speed of drinking

• The liver is the main organ of the body to remove alcohol from the bloodstream.   It does so at a rate of roughly one standard drink per hour.

1 standard drink = half pint beer = glass wine = pub measure spirits

• Fast drinking causes blood alcohol concentration (BAC) to rise rapidly.

• Drinking coffee, taking a cold shower, urinating or getting fresh air can not speed up the ability of the liver to cope with alcohol. 

Food

• The presence of food in the stomach slows the passing of alcohol in to the bloodstream.

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Type of drink

• The alcohol in fizzy and gassy drinks enters the bloodstream more quickly.

What are the risks of drinking too much alcohol?

Immediate risks include:

• Drunkenness
• Hangover
• Vomiting, stomach upset
• Poor judgement, loss of control
• Doing things you regret
• Unplanned, unprotected sex
• Aggression, impulsive behaviour
• Slowed reaction time affecting ability to drive, work
• Missing work, studies
• Money problems

Long-term risks include:

• Relationship/family problems
• Liver disease, certain cancers
• Wide range of physical illnesses
• Financial difficulties
• Job loss
• Alcohol dependence ('addiction')

• Mental health problems

How much is considered low-risk?

• The Royal College of Psychiatrists in the UK first devised the idea of weekly drinking limits in 1995.  Currently, an adults drinking is thought to be 'low risk' if they consume less than:

14 standard drinks* per week for women 21 standard drinks per week for men

These should be s-p-r-e-a-d out over the week, with at least 2 - 3 alcohol-free days.

* 1 'standard drink' = half pint beer = glass wine = pub measure spirits

Back to the top A word of caution: There is mixed evidence about the use of weekly limits.  They certainly do not apply to people who are pregnant, ill, run down, on medication or to children.

• Another guideline is to pace your drinking at roughly one standard drink per hour.  This is the rate at which a normal healthy adult liver can remove alcohol from the bloodstream.
• Know your limit

Most people know the point at which they lose control and put themselves at risk of immediate problems such as vomiting, aggression, unplanned sex and accidental injury.  It is most important to stay well below this limit in order to enjoy your drinking without unwanted consequences.

More about low-risk drinking

Low-risk drinking is not just about how much you drink but also the way you drink, ie, when, where and how. There are certain situations for example where it is not advisable to drink at all. These include any situation where you need to think clearly and react quickly or in situations of responsibility.  If you choose to drink, follow the low risk drinking behaviour route:

• Consider whether you will drink, what and how much you will drink before going out.
• Eat a full meal before drinking.
• Choose a safe way home before going out, and make sure you keep enough money to cover it.
• Keep your drink in sight at all times.
• Avoid mixing drinks, drinking doubles and drinking games.
• Avoid becoming drunk or losing control.
• Pace your drinking - about one drink per hour.
• Alternate with non-alcoholic drinks throughout evening.
• Do not drive after drinking or travel with someone who has been drinking.

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How strong are different drinks?

• The alcoholic strength of a drink is indicated on the label as % vol . 

o       Beer, lager and cider are about 4 - 6% vol (4 – 6 parts ethanol to 96 -94 parts water).  Wine is about 11 - 13% vol, while spirits are about 40% vol.

• To determine the amount (grams) of pure alcohol in a drink, the strength (% vol) is combined with the measure or size:

Strength of selected alcoholic drinks             

Type	Size	Alcoholic strength-vol %	Grams of Alcohol
Beer (lager, stout, ale)	Half pint/glass (284ml) Small can (330ml) Large can (500ml) Longneck bottle (330ml) Pint (568ml)	4.3%	9.8 11.4 17.2 11.4 19.5
Cider	Half pint/glass (284ml) Small can (330ml) Longneck bottle (330ml) Large can (500ml) Pint (568ml)	6%	13.6 15.8 15.8 24.0 27.3
Wine	Small glass (100ml) Medium glass (125ml) Quarter bottle (187.5ml)	12%	9.6 12.0 18.0
Spirit-based drinks	Longneck bottle 'alcopop'	5%	12
Spirits	Single measure (35.5ml) Double measure (70ml)	40%	11.2 22.4
Sherry/Port	Single glass (71ml)	20%	11.4

Note: there are 10g of pure alcohol in a ‘standard drink'

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Alcohol and accidents

• Alcohol consumption causes drowsiness, impairs judgement, concentration, co-ordination, and ability to perceive and react to hazards.  It also lessens inhibitions, leading to risk-taking behaviour.
• International studies have shown alcohol to be a risk factor in falls, burns, drownings, assaults, suicides, overdoses and workplace accidents.
• Alcohol is a factor in 40% of fatal road accidents in Ireland, and in 30% of all road accidents.
• • Even at the legal drink-drive blood alcohol concentration of 80mg/100ml, a driver is 6 times more likely to have an accident.
  • One third of pedestrians killed in road accidents demonstrate very high blood alcohol levels.
• A major study at the Mater Hospital, Dublin, found alcohol to be a factor in one quarter of all cases presenting to A & E (Casualty), with one in eight people presenting in a state of clinical intoxication.  Where injury does occur, alcohol can prevent post-injury recovery, and reduce survival from falls, near drownings and burns.

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