Drink less to keep the Christmas weight at bay

Alcohol does not provide any nutrients.
Alcohol does not provide any nutrients. / SUR
  • The health risks of drinking too much alcohol are well-known but very few know that one glass of wine can contain over 70 kilocalories

Nowadays, any sort of celebration involves drinking. During the festive period it is all too easy to end up drinking copious amounts of alcohol. It could be a spirit and mixer, a glass of wine, a beer or a cocktail. Social events, dinners, and parties are all linked to the consumption of alcoholic drinks. Before the party season gets under way it is good to know how much exercise you will have to do to work off the drinks.

According to the World Health Organization (WHO), a woman should not consume over 20 to 40g of alcohol daily, and a man should not consume over 40 to 60g. Anything more than this is considered harmful. However, as well as the effects of excessive alcohol cosumption, there are also calorific elements to consider when having a drink.

Currently, all we can do is work out the number of calories with maths, taking into account that a gramme of alcohol contains seven kilocalories (kcal). It all adds up quickly!

One gramme of alcohol contains more than the number of kilocalories in a gramme of carbohydrate or protein (4 kcal/g) but fewer than in a gramme of fat (9 kcal/g). However, there is an important difference to note, according to Ana Márquez, dietitian and nutritionist for Nutrisana: alcohol “is not a nutrient, whereas fat, protein and carbohydrates are; we use their energy for every day functions and to maintain homeostasis”, while alcohol contains calories. “They are considered 'empty' as they don't provide nutrition yet they are still fattening.”

So how do we measure the calories in a drink? It is very simple and Márquez gives a clear example: “Like with a sandwich, according to its size and ingredients, it will have a higher or lower calorie content, so a glass of an alcoholic drink, according to its size and what kind of drink it is, will have a higher of lower calorie content.”

Calculating the calories

To know how much of one drink to consume you should check the alcohol percentage, which indicates how much pure alcohol there is per 100 cubic centimetres. Furthermore, the higher the alcohol percentage is, “the more calorific it is”, says Ana Márquez. When you consider that most alcoholic drinks also contain sugar it can add up to a lot of calories. Here, the sandwich analogy comes in, given that a 30 ml drink will not have the same number of calories as a 200 ml glass or a 330 ml can.

Taking the example of a bottle of wine, on the label the bottle says that it has an alcohol content of 12%, which means that there is 120 ml of alcohol in a litre of wine. The first thing to work out is how many grammes of alcohol there are in this litre which can be calculated by multiplying the density of alcohol, 0.8 g/ml, with the millilitres of alcohol. So in this bottle, with 120 ml of alcohol, there are 96 grammes of alcohol in the litre. Next, this figure is multiplied by the kilocalories, remembering that 1 gram contains 7 kcal, and this reveals that in this bottle of wine there are 672 kcal. So, if you have a 100 ml glass, you are consuming around 67.5 kilocalories.

Using these calculations, it can be worked out that a can of beer contains 105 kcal and 50 ml of most spirits contains 140 kcal.

A study by the World Cancer Research Fund (WCRF) remarked that if a glass of wine contains 177 calories on average , this is the equivalent of eating two chocolate biscuits.

For most people to burn 100 calories, which is roughly the equivalent of a can of beer, they would have to run for ten minutes. So, if you drink three beers, you should do half an hour of intense cardio exercise to work it off. Remember that two beers more than this is considered excessive drinking.

Everyone knows that drinks with a higher alcohol content contain more grammes of alcohol, however the real problem, in Márquez's opinion is that “no one knows enough about the calories in alcohol”. In fact, she says that when she tells patients how many calories there are in alcohol they are shocked to discover than one gramme contains almost as much as a gramme of fat. “Even if they know this, they downplay the energy intake, they don't consider that they will have to go for a brisk half-hour walk to burn the calories in the glass of wine that they drank”, adds the nutritionist.

Harmful calories

Nevertheless, these kilocalories are not “bad” because they are fattening, but they are “harmful” because alcohol does not provide any nutrients “which means that our body is not going to put these calories to use in a positive way”.

Alcohol is a toxin, when consumed 95% is metabolised in the liver to get rid of it and the rest is released by excretion, through respiration, sweat, urine, saliva, and breast milk, which is why it is forbidden to drink alcohol during pregnancy and breastfeeding.