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Fitness & Health

08th Oct 2018

Intermittent fasting – is the hype justified?

With famous faces from Danny Cipriani to Chris Hemsworth swearing by intermittent fasting, here is what the science says

Alex Roberts

Fad diets like intermittent fasting come and go out of fashion, but the health benefits mean some are more worthy of sticking than others

Intermittent fasting is growing in popularity, with famous faces from Danny Cipriani to Chris Hemsworth all swearing by it at one point or another.

But is the hype justified? When looking to lose weight, there are three main ingredients involved in getting results:

  1. Creating a calorie deficit
  2. Eating foods that your body can handle
  3. A sustainable diet

When a diet works, it does so because of these factors – not because it’s low-carb, low-fat or based on what Fred Flintstone would have chowed down on 500,000 years ago.

What is intermittent fasting?

Intermittent fasting can be achieved in a number of ways. That’s because it involves consuming all your food in a certain window – then going without for a certain period.

Most of us fast naturally, anyway – by eating over 16 hours and then sleeping for around eight. Intermittent fasting often restricts the eating window even further, to a four or six hour period.

There are even more extreme approaches, such as the 5:2 diet. Over two days a week, calories are restricted to 500 or less. For the remaining five days, you would eat a normal, maintenance diet (calories in match calories out).

Is intermittent fasting for you? Here’s what the science says:

When does it work?

With fasting, food is restricted – so your calorie intake will be much lower. That in itself will likely lead to weight loss. Losing weight is often an overcomplicated process when, in a nutshell, burning off more energy than you take in is a proven way of getting there.

By restricting the volume of food you consume, you’ll also retrain your body to handle carbs more efficiently. This is known as insulin sensitivity. If you carry a lot of body fat, that probably means your ability to use the sugar from carbs could be controlled a little better.

Periods of intermittent fasting can help to re-tune your handling of insulin, meaning that you’ll be able to absorb and use sugars in a more effective way, with less of a cost to your body composition.

Read more: an office worker’s guide to weight loss

Who should avoid intermittent fasting?

You don’t necessarily need to fast to create a calorie deficit. However, if it helps you get there than perhaps give it consideration. Fasting benefits those who are capable of handling its regimented approach.

If it’s not your cup of tea, you can still lose weight by calculating the calories and macros you need, and then basing a sensible meal plan around those figures.

For building muscle, you need to consume protein every four or five hours. Carbs and fat are stored for a much longer duration in the body, so it’s not as much of an issue. If you’re trying to gain size, you need more regular protein feeds.

Will intermittent fasting will work for you? Weigh up the pros and cons, and see if it fits your routine.

Read more from JOE’s Ditch the Dad Bod series