Tuesday, 7 May 2013

The 8 Hour Diet - Review and Giveaway

The 8-hour Diet: Watch the Pounds Disappear, without Watching What You Eat!

Okay, so while being locked out of my apartment last week, I settled in to my local library and read the current issue of Women's Health. I have to admit, I have lost a lot of respect for the magazine.

It is one thing to give contradictory information over the life cycle of a magazine, it's completely another to have contradictory information within the same issue. (It also irritates me that they never list research properly, and draw ridiculous conclusions that isn't what the researchers found.)

This was noticeable particularly in the article about the 8 Hour Diet, which they were hugely in favour of because you get to eat whatever you want, and it's all supported by research. Yah!

Unfortunately, their other articles about food and diet, including their expert advice, totally contradicts the 8 Hour Diet.

So, I thought I would look into the diet myself and see what the hype is about.

What is The 8 Hour Diet?

The book is written by David Zinczenko and Peter Moore, who have both written diet books before and both have been editors of Men's Health, which might suggest why Women's Health was so happy with it.

The basics of the diet appears to be pretty simple: you can eat whatever you want, as long as you also include the 8 superfoods, and you can only eat for 8 hours a day (for example that would be from 10am to 6pm.) You are also supposed to do 8 minutes of high intensity exercise just before you break the fast, to start your body burning fat (because it will have already run through all the glycogen stored in the liver). 

The theory behind it: that by intermittent fasting, your body adapts and becomes better at burning fat.

You can check out an interview with Peter Moore on YouTube for a general overview (though doesn't give a large amount of detail).

What are the 8 Superfoods?

The book divides the superfood (groups) into two types: fat busters and health boosters, and suggests having one of each at every meal.

Fat Busters:
- eggs and lean meats.
- yogurt and dairy
- nuts
- beans and legumes

Health Boosters:
- Raspberries and other berries
- tree fruits
- whole grains (quinoa, oatmeal)
- spinach and green vegetables.

So, you are meant to eat all of those, everyday, within 8 hours. But you can still eat whatever you want. As long as what you want include those foods.

Benefits of the Program:

It says you can eat anything you want (though see down-sides). 
It doesn't require huge amounts of exercise, which is great for those who don't like getting sweaty.
It doesn't require too many strange and weird tasting foods.
You don't have to do it all the time. Even just doing the intermittent fasting 3 days a week is supposed to bring about weight loss. Though if you do it 7 days a week, obviously it works faster.

Down-Side to the Actual Diet:

Okay, so accepting that the claims might be true for a moment, are there any downsides to this type of diet?

Well, first off, you don't get to eat for 16 hours a day, which for some of us is going to be hard. The book's advice? Distract yourself with tasks such as cleaning the toilet. ... um, right. That might put me off eating for a few minutes, but I can't see it getting me from 6pm until I go to bed.

Second, as Women's Health mentioned themselves in the same issue, it's not a great idea to do hard exercise on an empty stomach and then not eat for another few hours afterwards. All athletes know that you should try to have some protein within 30minutes of a workout. You might burn fat this way, but you won't be able to get back out there and perform so well tomorrow or the day after. So that means you can only work out between the hours you can eat, which is pretty difficult if you have a job. This might be why the diet recommends just 8 minutes of exercise before breaking the fast.

Third, despite all the claims of the diet that you can eat what you want, no calorie restrictions, Yoni at Weighty Matters did some number crunching for the suggested 7 day plan:

"Because his recipes include calories (I wish every diet book's recipes did, kudos to Zinczenko) I crunched every day. If you follow his 7-day meal plan, you'll average 1,595 calories. From a low of 1,222 to a high of 1,805."

For a girl, that's a restrictive diet. For a guy?  It's definitely not eating whatever you want.

Fourth, what about all the research and evidence (again brought up by Women's Health in this issue) that says skipping breakfast is bad? Why does the same not apply here? Or we just saying all that research is now invalid because this other research (not listed) says its okay?

Issues with the Actual Book:

First of all, I really dislike how it is written. It's just way too over the top and promises everything. Even just the covers are annoying:

"In just 6 weeks you're going to have your best body ever. You'll be LEANER, HEALTHIER, MORE ENERGETIC. You'll have the flat, firm belly you've always wanted. You'll sleep better, think more clearly-and have much better sex. You'll look younger, feel younger, and dramatically cut your risk of the major diseases of our time.

You'll lose weight faster than ever-as much as 5 pounds a week-without restricting calories OR giving up your favourite foods.

My best body ever? That is going to take more than 6 weeks pal. Also, as much as 5 pounds a week? That's 2.26kgs a week, which is seriously unhealthy. Healthy weight loss is half that: 1 kgs -1.5kgs. Despite claims that it doesn't affect muscle growth, I just can't see how without working out you don't lose muscle bulk.  (Though, prepared to be proved wrong on this). Basically, just putting every human desire into a paragraph doesn't actually mean you are delivering.

Second, despite repeated claims that it's all based on research, they don't appear to ever properly cite the research they are basing it on. This is really bad scholarship and as a university tutor, I give them an automatic fail.

Third, a lot of people claim that they have stolen the idea (which since they have cited any of the research they are basing their ideas on, they sort of have anyway). Compare the book's claims to that of Martin Berkhan who talks about an 8 hour diet back in 2007 on his blog Lean Gains:

"The basic idea behind this protocol is to provide nutrients at a time where they will be used for recovery and repair, being the post workout window. In order to receive the benefits of nutrient partitioning, the protocol consists of a fasting period, lasting 16 hours. This means you initiate your first meal 16 hours before eating the last meal on the night before (which is easily done by skipping breakfast and lunch). Thus, ideally all eating is done within an 8 +-1 hour timeframe."

Lean Gains appears to actually have a lot of good information, if you are interested in Intermittent Fasting in relation to strength and fitness (not just weightloss).


The book itself is a bit of a fad. However, I'm not ruling out that intermittent fasting might work for some people. So, I'm looking for volunteers.


I'm offering free copies of the book for two readers who are willing to try the program for at least 2 weeks and report back.

 (I'm chickening out at the moment because of the half marathon training which I don't want to stuff up.)

Interested? Just leave a comment below saying why you'd like to give it a go.

Update: having become interested in another diet based on intermittent fasting, I challenged my volunteer Jo to a Hunger Games: 8 Hour Diet Vs 5:2 Diet. Follow the links to see the results!


  1. We have one very brave little guinea pig! Jo has agreed to give it ago, though strangely her comment didn't show up. If you've tried to leave a comment but don't see it, try emailing me at: b.greentr@gmail.com.

  2. I'm going to try it along with daily workouts of Cardio and strength training

    1. If you're happy to report back and give us all the details as you do it, I'd be happy to send you an ebook version of it from Amazon. (If you already have your own copy, you could still report back!)

  3. Hey everyone,
    I myself have adapted the 8 hour diet for quite some time now, but always had problems tracking the hours I was allowed to feast and fast.

    Luckily, I know how to create iPhone Apps - so I built an App just for that: Tracking your 8 and 16 hour phases.

    It's for free and really easy to use so I would like to share it with you guys. You can find it by searching for "8 16 hours" in the App Store or go to 816hoursapp.jimdo.com

    I'm looking forward to your feedback - if you like it please spread the word!


  4. I want to try 8 hour diet program for 2 weeks, thanks! Check out my article about 8 hour diet on http://www.quickweightlossforall.com/diets/8-hour-diet/ Thanks!