When we drink an alcoholic beverage, we are consuming the chemical ethanol, which is obtained during the fermentation of sugars in fruits, grains and vegetables. These sugars react with yeast or bacteria, producing ethanol and carbon dioxide, and one unit of alcohol, which is roughly 8 mg of ethanol, provides our body with 65 calories.
Beers and spirits are made from a variety of fermented cereals, with hops in the case of beer and barley and rye for whisky. Vodkas are made from grain or potatoes, gin from juniper berries, rum from sugarcane residues or molasses and cider and wine are made from fermented fruit.
How much alcohol each drink contains is affected by the amount of time it is left to ferment. Making spirits also includes a period of distillation, and this can lead to water being removed and a stronger drink, as well as adding flavours.
What happens when we drink alcohol
From your first sip, alcohol affects both the brain and the body. A couple of drinks can lower your inhibitions and make you more sociable, but drinking too much can interfere with basic functions such as walking, thinking and talking. Some people also say things they don't mean and adopt behaviour that is out of character.
Some of the alcohol's effects will disappear after a night's sleep, but as it is a diuretic, alcohol causes increased passing of urine and the removal of fluids from the body can cause dehydration. Drinking too much can lead to a hangover, and besides dehydration, you may suffer from severe headaches, dizziness and sickness. Alcohol can also interfere with sleep patterns, and may remain in your system the following morning.
Drinking heavily on a regular basis may mean you are in the "increasing risk" or "higher-risk" category for drinking. Alcohol can impact a number of areas of your life, and can even encourage the development of long-term health conditions such as cancer, heart disease and liver disease. High blood pressure and reduced fertility are also common longer-term conditions.
Drinking alcohol regularly can also affect your waistline as it contains a surprisingly high number of calories. Carrying too much weight also increases the risk of developing some serious health problems.
You can help yourself cut down and control your drinking by:
• Planning your drinking before you start, setting your limits and sticking to them
• Telling family and friends about your plan to cut down so they can support you
• Aiming to cut back a little each day. Your chances of success will be improved
• Choosing smaller drinks with a lower alcohol content. This may mean switching to a small glass of wine, bottled beer rather than pints and swapping stronger varieties for weaker ones
• Drinking a pint of water before you start and when you get home to help you stay hydrated. You can also alternate between alcoholic and non-alcoholic drinks for the same effect
• Aiming to have at least one day each week when you don't drink alcohol at all.
Remember the healthy limits
If you are male this means no more than 21 units of alcohol a week and no more than three to four units a day. For women this means no more than 14 units a week and a maximum of two to three units a day.