Does Alcohol Make You Fat? Here’s the Science

If you want to lose fat, alcohol is a definite no-no. Even just a few drinks at the weekend will be turned into fat and go straight to your belly. 

If you’re serious about getting in shape, you’ll need to follow Donald Trump’s lead and cut out alcohol completely.

Or will you? 

Contrary to popular belief, only a fraction of the alcohol you drink is turned into fat. What’s more, studies show that it’s possible to drink alcohol on a regular basis – every day in some cases – and still lose fat.

Here’s a closer look at the science on alcohol and weight loss, and what it all means for you.

Does Alcohol Turn Into Fat?

Alcohol can contribute to weight gain. But that’s not because it turns into fat. Rather, the main effect of alcohol is to reduce the amount of fat your body burns for energy.

In fact, just two drinks of vodka and sugar-free lemonade, with each drink containing just under 90 calories, has been shown to cut whole-body lipid oxidation (a measure of how much fat your body is burning) by more than 70% [1].

You can see this for yourself in the figure below, which shows fat burning before (on the left) and after (on the right) alcohol consumption.

Rather than turning into fat, the main fate of alcohol is conversion into a substance called acetate. In fact, blood levels of acetate after drinking the vodka were 2.5 times higher than normal. And it’s this sharp rise in acetate that puts the brakes on fat burning.

To summarize and review, here’s what happens to fat metabolism after drinking alcohol:

• A small portion of the alcohol is converted into fat. Of the 24 grams of alcohol consumed in this study, roughly 3% was turned into fat.
• Your liver then converts most of the alcohol into acetate.
• The acetate is released into your bloodstream and takes precedence over the metabolism of protein, carbohydrate, and fat.

The way your body responds to alcohol is similar to the way it deals with excess carbohydrate. Although carbohydrate can be converted directly into fat, this doesn’t happen unless you’re eating large amounts of it [2].

Instead, one of the main effects of overfeeding with carbohydrate is that it replaces fat as a source of fuel. By suppressing fat burning, it enables the fat in your diet to be stored a lot more easily, as well as reducing the amount of stored fat that’s burned off.

To sum up, the idea that alcohol automatically turns into fat and goes straight to your waist is mistaken. Alcohol does put the brakes on fat burning while it’s being metabolized by your body [3]. But it’s no more likely to contribute to weight gain than excess calories from carbohydrate or fat.

Does Alcohol Slow Down Your Metabolism?

Your resting metabolic rate, more generally known as your metabolism, is typically defined as the number of calories your body burns at rest.

It’s the energy required to keep your heart beating, your lungs drawing in air, the cells in your brain sending signals to each other, and all the other stuff involved in keeping you alive.

Some say that alcohol contributes to weight gain by slowing your metabolism. Because your body can’t store alcohol and has to deal with it straight away, other metabolic processes suffer. Carbohydrate and fat won’t be metabolized as efficiently, and as a result your metabolism will slow.

Or so the theory goes, anyway.

It’s true that metabolizing alcohol takes precedence over carbohydrate and fat. 

Unlike carbohydrate and fat, alcohol can’t be stored, and your body wants to get rid of it. This is where the liver gets involved. Enzymes in your liver convert alcohol into a number of different substances, which allow your body to break it down and eliminate it.

Metabolizing alcohol requires energy, which is known as its thermic effect. The thermic effect of alcohol is around 15%, which is higher than both fat and carbohydrate, which have a thermic effect of 2-3% and 5-8%, respectively [3].

In other words, for every 100 calories that come from alcohol, roughly 15 of those calories will be burned off in the process of metabolizing and processing that alcohol.

However, there’s no evidence to show that alcohol has any adverse effect on your resting metabolic rate.

In fact, when researchers compared diets containing alcohol with diets containing no alcohol, they found no difference in resting metabolism between the two [4].

In a follow-up trial, drinking two glasses of wine every night for six weeks had no effect on resting metabolic rate when it was measured under controlled conditions [5]. 

Here’s how the researchers sum up their results:

“The primary findings of this study indicate that in free-living subjects, the addition of two 135 ml glasses of red wine (13% alcohol) to the evening meal over a 6-week period does not influence body weight, body composition or resting metabolism.”

Because it can’t be stored for later use, unlike fat and carbohydrate, alcohol goes to the front of the queue to be dealt with by your liver. But this is a sign your metabolism is working as it should. Consumed in moderation, there’s no evidence that alcohol slows or impairs your metabolism.

RELATED: Metabolic Confusion: Why You Can’t Outsmart Your Metabolism

Does Drinking Wine/Beer/Vodka Make You Fat?

Drinking wine, beer, vodka or [INSERT DRINK OF YOUR CHOICE] won’t automatically make you fat.

In fact, there’s plenty of research out there to show that you can drink alcohol and still lose fat, just as long as you’re sensible about it.

In one trial, researchers from Colorado State University got a group of men to drink two glasses of wine every night with their evening meal [5]. 

After six weeks, nothing much happened. The men’s weight didn’t change, and no fat was gained.

Another study from the same research group shows much the same thing [6]. Drinking two glasses of wine, five nights a week for ten weeks, had no effect on body weight or fat percentage in a group of sedentary, overweight women. 

In a study published in the International Journal of Obesity and Related Metabolic Disorders, German scientists assigned a group of overweight and obese subjects to one of two 1500-calorie diets [7]. The first diet included a glass of white wine every day and the other a glass of grape juice.

The result?

Three months later, there was no significant difference in weight loss between the two groups. A diet where 10% of the calories came from white wine worked just as well as a diet where 10% of the calories came from grape juice.

Obviously there’s a balance to be struck. You don’t need to cut alcohol out completely. But if you’re trying to lose weight, cutting your intake in half is a good place to start.

The simple way to do this is alternate whatever you’re drinking with water or some other low-calorie drink. So you’d have a cocktail… then a glass of water… then a cocktail… and so on. If you drink a glass or two of wine every night, try drinking every other night instead.

In short, there is nothing inherently fattening about alcohol. As long as your overall diet puts you in a calorie deficit, you can drop fat without ditching alcohol.

Does Alcohol Cause Weight Gain?

Alcohol, in and of itself, doesn’t cause weight gain. What causes weight gain is consistently eating too much food relative to your energy needs. In that sense, excess calories from alcohol are no different to excess calories from carbohydrate or fat.

However, where alcohol does differ from carbohydrate and fat is in the way it affects your behavior. 

Specifically, alcoholic drinks can contribute to weight gain because they have a “disinhibiting effect,” making it harder to resist the temptation to eat certain foods [8].

So what does that mean exactly?

For one, studies show that you tend to eat more if a meal is served with an alcoholic drink than you would if that same meal was served with a soft drink. 

A Canadian study shows that an apéritif (an alcoholic drink taken before a meal to increase the appetite) increased calorie intake to a greater extent than a carbohydrate-based drink [9].

Researchers from Denmark’s Royal Veterinary and Agricultural University report similar results [10]. When a group of men was given a meal and allowed to eat as much as they wanted, they ate more when the meal was served with beer or wine rather than a soft drink.

So you get hit twice — once from the calories in the alcoholic drink, and then again from the subsequent increase in calorie intake.

When a group of women was asked to taste cookies after drinking vodka and diet lemonade, or a placebo that smelled and tasted similar, they ended up eating more after drinking the vodka [11]. 

Of the three main lifestyle factors that encourage excessive eating, alcohol is at the top of the list, ahead of watching TV and sleep deprivation [12].

Picture the scene: It’s a Friday night, and you’re out for dinner with some friends. You’ve decided in advance that you’re going to indulge a little, but only in moderation.

You sit down for some pre-dinner drinks, and promise yourself that you’ll have just one. But that one is soon followed by another, and then another.

Like the fading light from a setting sun, your ability to resist the urge to eat certain foods gradually dims. Then the “what the hell effect” kicks in, and any attempt to put a limit on what you eat is silently but swiftly abandoned. 

Inhibitions are lost, and the dietary restraint switch is flicked to the off position. It’s a slippery slope that ends with a trip to McDonald’s in the early hours of Saturday morning.

But that’s not all. 

The workout you’d planned to do that day goes out the window, replaced with you binge-watching an entire boxset on Netflix. You’re tired, hungry, and annoyed at yourself for letting things slide.

To make yourself feel better, you end up eating even more, embarking on a junk food binge lasting anywhere from a few hours to a few days.

I already messed up, you say to yourself, so I’m going to do what I want for the rest of the weekend. The decision is made to drop out of your latest mission to get in shape and “start fresh” at a later date, be it next week, next month or next year.

Final Thoughts

Alcohol itself, consumed in moderation, isn’t going to have a negative impact on fat loss as long as it’s accounted for in your weekly calorie budget. 

However, where alcohol can torpedo your attempts to get in shape is via the knock-on effect it sometimes has on your eating and exercise habits in the hours and days that follow. Too much alcohol has the potential to damage your progress in a way that extends beyond its calorie content alone.