No matter the season, social events with family and friends are part of our everyday life. Our social and mental health should always be a priority and plays a major role in our overall happiness and well-being.

For many, alcohol plays an integral role in social gatherings and celebrations. Its effects on society are wide-ranging, with one to two drinks per day associated with positive health benefits and excessive alcohol consumption linked to alcoholism and cirrhosis.

You certainly don’t need to consume alcohol to enjoy social events and I’m not here to tell you how much or how frequently you should or shouldn’t drink.

I’m going to discuss alcohol’s impact on body composition, specifically fat loss. As with many nutritional topics, there’s an abundance of myths and misconceptions. The best place to start is with the scientific evidence. Before doing so, let’s look at how alcohol is metabolised by your body.

Some alcohol basics

Alcohol is toxic and has no nutritional value. It contains 7 calories (kcal) per gram, meaning it is almost as energy dense as fat.

• 1g Carbohydrate = 4 calories
• 1g Protein = 4 calories
• 1g Alcohol = 7 calories
• 1g Fat = 9 calories

When you drink alcohol, it is absorbed from your stomach and intestines. Before entering your circulation, it is metabolised in your liver. Your liver breaks down some of the alcohol into acetaldehyde and then into acetate.

Alcohol is treated as the preferential fuel source ahead of carbohydrates, fat, and protein. Which makes sense considering the metabolic by-products of alcohol – acetate and particularly acetaldehyde – are toxic.

Once acetate enters your blood, fat burning is suppressed throughout your body. As a result, most of the fatty acids in your blood are being stored.

Alcohol and fat gain

Due to alcohol’s inhibitory effects on fat-burning, this has caused many to believe that alcohol ingestion alone will interfere with fat loss. It doesn’t. Alcohol only causes fat gain when consumed in excess of calorie needs.

A similar logical fallacy is seen with the carbohydrate-insulin hypothesis and obesity. This has been debunked and discussed in greater detail in this previous blog post.

It’s important to note that fat storage is an ongoing process and fatty acids are constantly entering and exiting fat cells throughout the day. Net fat gain or loss is most closely related to energy balance over time.

Alcohol will only affect fat balance (gain and losses in body fat) over 24 hours if you consume more calories than you are expending, resulting in a net energy/calorie surplus.

In a study where 14 men were given 270ml (1.5 standard glasses) of red wine with dinner for six weeks, followed by the same period of abstinence, there was no effect of alcohol on body weight, body fat, or calorie intake.

In a similar study, 20 overweight women were given 190ml (1 standard glass) of red wine with dinner for five days of the week over ten weeks, followed by the same period of abstinent. Again, there was no effect of alcohol on body weight or body fat.

Alcohol and fat loss

Contrary to popular belief, there’s scientific evidence to indicate that alcohol consumption can be a part of an effective fat loss program, once you are mindful of your total calorie intake.

In a weight-loss study on obese men and women, researchers separated subjects into two groups with a total calorie intake of 1,500kcal. One group drank 10% (200ml) of their calorie intake from grape juice, while the other group drank 10% (200ml) of their calories from white wine.

The study lasted three months and all subjects achieved significant weight loss. When the groups were compared, there was a trend for more weight loss in the wine group. Despite alcohol’s effects on fat-burning acutely, weight loss still occurred!

Pitfalls and considerations

The issue with alcohol consumption and fat-loss often boils down to the effect alcohol has on our self-control. This can become even harder after a couple of drinks, as appetite tends to increase leading to a higher food intake.

In a study on alcohol consumption and food intake at a buffet-style lunch, 26 men attended the study facility on three occasions. Thirty minutes before lunch, subjects either rested, were given 330 ml of a non-alcoholic lager or 330 ml of the same lager spiked with 3 units of alcohol. Calorie intake was significantly higher (~15% excluding calories from alcohol and 30% including alcoholic calories) following consumption of an alcoholic lager compared to the other two occasions.

It’s generally the combination of alcohol and the overeating around it that can undermine fat loss progress.

Another area that alcohol can negatively impact is our sleep. Sleep is one of the most neglected weapons in our biological armoury.

Research suggests that, although alcohol can induce sleepiness, once blood alcohol levels decrease, you can find yourself more wakeful than usual, which can lead to poorer sleep quality. Restricted and poor sleep results in an increase in food intake and a reduction in energy expenditure.

Conclusion

Alcohol only causes weight gain when consumed in excess of calorie needs over time. Light to moderate alcohol intake (1-2 drinks per day maximum) can be included in an effective fat loss program; however, be aware of the potential impacts on appetite.

For those who prefer to go beyond moderate intakes, check out some practical tips on how to include alcohol within your diet without sabotaging your fat loss efforts (link to blog post).

Kevin Garde
Nutritionist and Bodyscan Consultant