The 8 Hour Diet: Everything you need to know about intermittent fasting

It's all in the name...

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Think it sounds too good to be true? Read on to find out what is the 8 hour diet, how it works, and what you can eat and drink...

Sticking to any diet can be tricky at the best of times, especially when there's some foods you have to eat more of than others - like on the high protein diet- and it's even harder when you have to avoid some foods, like on the Keto diet. But one of the best things about the 8 hour diet is you don't have to worry about any of that.

Also known as the 16:8 diet, the 'eight hour diet' is a form of intermittent fasting that involves eating normal meals for eight hours, and fasting for the remaining 16 hours of the day. The diet has becoming increasingly popular, especially among Hollywood A-listers like Nicole Kidman and Hugh Jackman, as it promises to kick bodies into fat burning mode. Here's everything you need to know...

What is the 8 Hour Diet plan?

The eight hour diet involves only eating within an 8-hour window and fasting for the remaining hours of the day. This gives your body a long break from when you ate your last evening snack until breakfast, allowing time to 'reset', and process all the nutrients you've consumed, get rid of toxins, and burn calories.

Research around intermittent fasting has shown that when the body exhausts its sugar stores, it will start burning fast - known as 'intermittent metabolic switching' (IMS). While the body is getting its energy from glucose it's maintaining or gaining weight, but when the switch happens weight is lost.


The 8-Hour Diet by David Zinczenko and Peter Moore - £6.16 | Amazon
Published in 2013, the 8-Hour Diet book has all the information, factoids, meal plans and tips for following through with the 16:8 diet.

So, rather than restricting what you eat, the eight hour diet limits when you can eat - we've all read the advice that you shouldn't eat after 7pm if you're trying to watch your figure, right?

And even better, you can choose which days you follow the 8 hour diet. Do it everyday, or just once or twice a week if you feel like it. The more often you do it, the more weight you could lose.

When can I eat on the 8 hour diet?

It's completely up to you as to when you want your eight hour period to fall, and it mainly depends on your schedule. If you work your day around the kids, why not set your 8-hour period to fall in line with them?

For example, you could eat some healthy cereal when you get back from the school run around 9:30am, and have your dinner around 5pm when they're back at home and it's time for tea.

Most people who follow the 8 hour diet usually eat breakfast at 10am, lunch at 2pm and dinner at 6pm and then have breakfast at 10am the next day, leaving a 16 hour gap. In fact, research has identified the best time to eat breakfast, lunch and dinner for weight loss.

Of course, if you're trying to lose weight it's a sensible idea to eat healthily during your 8 hours. There's no calorie limit - unlike other popular diets such as the Fast 800 - or banned foods (yippee!), so it's a great one to go for if it's going to be a struggle to control the foods you eat.

Popular eight hour diet time windows:

  • 7am to 3pm
  • 9am to 5pm
  • 12pm to 8pm
  • 2pm to 10pm

What can I drink after my 8-hour period?

The only drinks you should be having outside of the 8 hour period are water, unsweetened coffee or tea. Hydration is super important on the 8 hour diet and drinking lots of water has been proven to quell any hunger that you might be experience. 

However, reaching for a calorie- or sugar-rich drink is one of the main reasons that people give up on the diet, as they don't see any results.

A lot of our favourite drinks have hidden sugars in them without our knowledge. For example, we may think that Diet Coke doesn't have sugar or calories in it so it makes the perfect drink for this diet. But Diet Coke is just one of the many diet drinks that contains artificial sweeteners, which can disrupt weight loss in other ways.

How long does it take to lose weight on the 8 hour diet?

According to a 2015 study, there's a typical weight loss of around seven to 11 pounds over a ten week period if the eight hour diet is followed correctly.

The diet is perfect for those of us who tend to graze on food throughout the day and struggle with sticking to a strict diet plan, but while there's no prescribed daily calorie intake, you'll want to avoid packing in too many calories during the eight hour window. 

This is because eating less calories than you burn is a proven way to lose weight. According to another 2015 study, a calorie deficit of around 500 calories per day is sufficient for weight loss, and is also unlikely to significantly affect your hunger or energy levels. Check out these low calorie meal ideas to help you get the most out of the eight hour diet.

Is the 8 Hour Diet healthy?

Author of The 8-Hour Diet David Zinczenko claims his 8-hour weight loss plan has loads of health benefits. Apart from the obvious one of losing weight, fasting a few times a week have been proven to regulate insulin levels, therefore protecting against diabetes, not to mention cancer, and dementia.

New research has also show that fasting for a certain period of the day can speed up cell recycling and regeneration, which means you're less likely to get ill, and it has linked periodic fasting to lower risks of heart disease, diabetes, and ageing.

However, it's worth bearing in mind that the eight hour diet shouldn’t be seen as a substitute for a balanced diet rich in whole foods - you should still be eating balanced, nutrient-rich dishes while following the plan.

In addition, if you have any underlying health conditions, are on medication or have a history of disordered eating, you should talk with your doctor if you're considering trying this diet. The eight hour diet is not recommended if you’re trying to conceive, pregnant, or nursing.

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Lifestyle Writer

Gemma Chandler is a lifestyle writer specialising in kids' educational media across a range of topics including nature, history, science and geography across digital, print, social media and video channels. She joined Creature & Co. at 2015, shortly becoming Digital Editor of National Geographic Kids magazine.

With contributions from