Drink Driving: Your Body and How Many is Enough

Drink driving ranks as one of the most serious traffic offences. The UK has drink driving limits set by law and blood alcohol content is important when proving whether drivers are over the limit. But there are certain factors including body weight and even gender that can make a difference to blood alcohol content.

Drink Driving Breath Tests

If a driver is stopped under suspicion of drink driving the police will usually perform a roadside breath test. The police can stop drivers at random and perform tests if they see motorists driving without due care. Drivers who do fail the breath test will be arrested and taken to a police station where two further breath tests will be taken. Drivers do have the right to request a blood or urine test if the breath test proves to be 40% over the legal limit.

Drink Driving Limits in the UK

In the UK the drink driving limit can be measured by blood, urine and breath. Limits have been set by law and these are:

• 107 milligrams of alcohol per 100 millilitres of urine
• 35 micrograms of alcohol per 100 millilitres of breath
• 80 milligrams of alcohol per 100 millilitres of blood

Misconceptions over Units of Alcohol

One common point of confusion for drivers is the amount of units of alcohol that can be drunk and still be regarded as safe to drive. Alcohol units are measured by both the size of the drink and the strength of the alcohol. One pint of beer with a three percent alcohol by volume (ABV) strength would be considered as two units. A standard glass of wine, which is 175 ml with a twelve percent ABV, would be considered 2.1 units. Although these are helpful guidelines there is no actual way to safely ensure driving below the legal limit based on units of alcohol. A number of factors have to be taken into account when it comes to the body’s ability to process alcohol.

Your Body and Blood Alcohol Content

There are several different issues that will make a difference to how quickly the body can process and eliminate alcohol from the blood stream. It takes approximately one hour for a liver to process 15ml of alcohol, but that is a healthy liver. One unit of alcohol is 10ml and how long it will take to process alcohol will vary between drivers. People with liver disease can take much longer to process alcohol. But heavy drinkers can actually have very active livers meaning they will be able to process alcohol quickly.

Body Type and Processing Alcohol

The driver’s weight will also make a difference to the blood alcohol content. A larger person will hold more water in their body meaning the alcohol will be spread thinly throughout the body. This can show in a lower blood alcohol reading than a smaller person who has drank the same amount of alcohol. The muscle and fat content of a person’s body will also make a difference to the blood alcohol ratio. Fat does not absorb alcohol effectively but muscle, which has a high water content, does.

Drinking on an Empty Stomach

There is a wise rule that states people should never drink on an empty stomach. Drinking without eating will mean that alcohol is not absorbed effectively and will stay in the blood stream longer. Food does help to absorb alcohol and those who go without food before or during drinking will have a higher blood alcohol content ratio. Certain medication can also make a difference to blood alcohol content and can slow down or even block the body’s ability to process alcohol. Older people regardless of medication use will also usually have more difficulty processing alcohol than younger people who can process alcohol quickly.

Alcohol Processing and the Gender Difference

Gender does make a difference when it comes to the body’s ability to process alcohol. Women generally have less water in their bodies than men and the alcohol takes longer to be eliminated from the blood stream. The fat, weight and muscle content carried by the female will of course make a difference to processing the alcohol. But in general, a woman will have a higher alcohol to blood ration even if a man and woman were to drink the same amount of alcohol over the same amount of time.

In the UK there are over 2000 fatalities each year caused by drink driving accidents. Every driver is different when it comes to absorbing alcohol and their reactions will also differ on the road after drinking alcohol. The safest way to be sure that alcohol will not affect your driving is to eliminate drinking altogether before driving.