Tuesday Tip: Fasting for fat loss

Tuesday Tip: Fasting for fat loss 🚫

I’ve had quite a few people ask me about this recently so thought it was worth revisiting. Various forms of fasting have become extremely popular in the past few years, due to purported health and weight loss benefits. There are various methods – from ‘eating windows’ of 6-8 hours a day (intermittent fasting), to 24-48 hr fasting etc. The claim is that fasting will

accelerate weight and fat loss and sometimes that it will ‘reset’ your metabolism/system etc. However, the data doesn’t actually support these claims.

A recent 2021 study investigated fasting and the impact on fat loss. It tested 3 protocols – fasting with a calorie deficit, fasting without a calorie deficit and a calorie deficit with no fasting. The group that fasted without a calorie deficit overall did not lose fat or weight. Both groups with the calorie deficit lost body weight. However the group that fasted lost less fat and more

muscle. Whereas the group that just had the calorie deficit lost mostly fat. There was no impact of fasting on their metabolism either.

So in short, fasting had no overall benefit in terms of fat loss and in fact could result in increased muscle loss rather than fat. It is actually the calorie deficit that causes the weight or fat loss.

There are claims that will boost your metabolism but research suggests that fasting has the same or negative effects on metabolism compared to a calorie deficit from other ‘diets’. When you severely limit calories, your body slows down basic functions to conserve energy. Instead of boosting your metabolism, you may experience a reeducation of up to 20% your BMR.

So there is nothing ‘magic’ in fasting, the only way it aids weight loss is if it helps someone create a calorie deficit (with the proviso it may result in some muscle loss too). So it really is just another tool to help you create a calorie deficit – it may work for some people, and if so that’s great but it’s not for everyone and it doesn’t offer any significant benefits to any other method of reducing calories.

It’s also worth noting that fasting can have impacts on gastrointestinal health and increases the risk of acid reflux etc so should be undertaken with caution.

Happy Tuesday 🤗

xx