This is a question that comes up all the time with clients. When you’re working hard to change habits around food it can feel like a step too far to stick to water when the weekend comes. That’s why I rarely suggest clients give up entirely; I’m interested in promoting sustainable weight loss that makes room for real life.

However, alcohol can absolutely affect your ability to lose weight, especially if you drink too much and too frequently. In this article I’ll explain four reasons why alcohol can sabotage your goals plus share some tips for mitigating the effects.

The Evidence

First some good news. There have been numerous studies suggesting that moderate drinking will not affect your weight.  In a 2010 study  of nearly 20,000 women, non drinkers were more likely to put on weight than moderate drinkers. The study was published in the in the Archives of Internal Medicine and tracked participants for 13 years.

However, there is clear evidence that binge drinking expands your waistline. Researchers from the University College of London found that men who drank approximately seven drinks and women who drank approximately four drinks in one session had larger waists than moderate drinkers. Notably, participants only had to ‘binge’ once a month to see their bellies expand. For women, the difference in waist size between bingers and ‘non bingers’ was a whopping 10cm.

So what’s the right amount? If you are serious about losing weight then limit yourself to one or two drinks on Friday and Saturday nights.

Four Reasons Alcohol Leads to Weight Gain

1) We tend to eat more when we drink alcohol.

We all know this (the bread basket can disappear pretty quickly next to a bottle of wine) but there are plenty of studies to back it up. Research shows people eat around 30 percent more food when they consume alcohol. Certainly as our inhibitions disappear so does our self consciousness about what we’re eating along with our willpower to stick to our plan. In addition, alcohol affects our blood sugar levels which may result in an instinctive need to balance levels by eating more.

2) The second truth is that when you’ve consumed alcohol it’s harder for your body to burn fat.

This is because alcohol affects glucagon – the hormone that works to raise blood glucose levels and to break down body fat. In addition, the liver prioritises processing alcohol before doing the many other jobs that it has to do.

3) Skipped the TRX class thanks to that second glass of wine?

It’s no surprise that alcohol affects our motivation to exercise the next day and also our performance. However, if you can bite the bullet and get to the gym, it will be worth it; you get an endorphin rush, sweat out toxins and might make healthier food choices. A 2014 study published in The International Journal of Obesity found that interval training lowers levels of the hormone ghrelin, which is known to stimulate appetite. 

4) Finally, drinking affects your sleep.

In fact, alcohol is ‘the biggest suppressor of REM sleep we know’ according to Dr Mathew Walker, neuroscientist and best selling author of Why We Sleep. We might think that having a ‘nightcap’ will help us sleep like a baby however the reality is that alcohol leads to fragmented sleep, where we wake up several times during the night. The upshot? Research shows it leads to us eating an extra 300 calories a day.