Where do calories in alcohol come from?

Jane Peyton, Founder of the School of Booze explains what's on the mind of every drinker

Many of us are used to counting the calories in our food but are often less demanding about our drinks. We know that alcoholic drinks contain calories but we choose to believe that, somehow, they don’t really count. Some drinks will obviously have more calories than others but where do they come from and can they be reduced without compromising on enjoying a great-tasting drink?

Firstly, we need to look at the source of ethanol which is the type of alcohol consumed in a drink. When the sugars in fruit, plants, honey, or sap are fermented by yeast, some of them are converted to ethanol alcohol. In wine the sugars come from grapes, from cereals in beer, and apples in cider.

Alcohol itself is high in calories and in wine, beer and cider accounts for up to two-thirds of the calories. The rest comes from sugars (carbohydrates) some of which are too complex to be fermented. They contribute to the body and the mouthfeel of a drink.

"Alcohol itself is high in calories and in wine, beer and cider accounts for up to two-thirds of the calories"

A gin and tonic

Spirits are different because they are produced by heating fermented grape or apple juice, or fermented cereals such as wheat, barley or rice. Steam from the heated liquid contains alcohol which condenses to become the spirit—high in alcohol, but with no carbohydrates as long as the producer adds no sweeteners.

Adding sweeteners, also known as back-sweetening, is widely practised in wine making and cider production when unfermented grape or apple juice, or sometimes syrups or artificial sweeteners, are introduced just before packaging. In some cases this practice is to balance acidity, but the intention is usually to make the liquor appealing to as many people as possible by producing an unchallenging, easy-drinking libation.

What happens in the body after an alcoholic drink is consumed?

Liver damage due to alcohol

Too much drinking can cause liver damage

The way our body deals with alcohol is connected to the weight-gain that some people experience if they drink regularly. The liver processes alcohol by releasing enzymes that transform it into acetate which the body burns as energy.

However, the body prioritises activities and if it is burning acetate, it is not burning fat. Some residual carbohydrates in the drink are converted to fat and hence the chance of piling on the pounds.

Calories are related to alcohol strength

Calories from alcohol are related to the product strength, so neat gin at 37.5% ABV (alcohol by volume) will be higher in calories than wine at 13% ABV, although the effect must be balanced against the serving size.

For comparison, a 175 ml glass of red wine would normally contain around 150 calories, whereas a 25 ml shot of gin is approximately 97 calories. But if the wine was served in the same measure as the gin, it would be around 22 calories.

"However, the body prioritises activities and if it is burning acetate, it is not burning fat"

Empty calories

calorie counting tape around a wine bottle

Calories from alcohol are sometimes described as “empty”, meaning they have no nutritional value and no benefit for the body.

In fact there is some evidence that small amounts of alcohol can reduce the threat of coronary heart disease by raising the amount of “good” cholesterol (High Density Lipoprotein) and lowering the risk of arteriosclerosis (hardening of the arteries). Alcohol is a vasodilator meaning it dilates blood vessels leading to unimpeded flow and ideal pressure.

There can be other benefits to alcohol, because during fermentation the nutritional value of the grape or apple juice, or cereal increases in a transformation known as biological ennoblement.

In this process, the goodness contained in the fruit or cereal is enhanced. Beer, for example, contains minerals, vitamins, amino acids, proteins and is especially rich in the vitamin B-complex essential in almost every process in the body including energy production, digestion, central nervous system, healthy hair, skin, and nails.

Do remember, though, that as well as watching calories, you should always drink responsibly and watch the number of alcohol units that you are consuming.

"In fact there is some evidence that small amounts of alcohol can reduce the threat of coronary heart disease by raising the amount of “good” cholesterol"

How to choose a reduced calorie alcoholic drink

If sugar content in drinks is reduced, and consequently the calories too, should we expect the taste to be compromised? No, producers are increasingly conscious about creating drinks that are suitable for healthier lifestyles with the same great flavours and we have some simple tips when choosing your favourite tipple:  

  • Choose lower alcohol drinks because the majority of calories come from the alcohol itself—generally, the lower the alcohol strength, the lower the calorie count
  • Select drinks that have not been back-sweetened—with wine and cider this means they will be dry on the palate
  • Pick a beer that includes other cereals in addition to barley because they contain more fermentable sugars meaning fewer carbohydrates and calories
  • With spirits be aware of the calorie content of the mixer
  • Choose a smaller serving

For more information about your favourite drinks and online courses, visit School of Booze

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