
In The 4-Hour Body, Ferris documents the results of his extensive studies which he conducted on himself in the years up until 2010, when it was published.
The trailer for The 4-Hour Body is here – a cool video if you have a couple of minutes.
He has remarked himself that since the book was published, science caught up and provided the empirically substantiated evidence for a lot of the results he had found in his own studies on his sample of 1, himself.
One finding for which I doubt there has been significant follow-up research conducted, but which I use on a weekly basis is that of The Cheat Day.
Perhaps obviously, but maybe not, a Cheat Day is a day off, when participants of a dietary regime eat as much of and whatever they want.
In the book, the Cheat Day is supported on a scientific basis, including explanations of the impact of a short-term spike in insulin levels which supports metabolism for the remainder of the week, amongst other things.
My reasons for taking a Cheat Day are perhaps less stringently evidenced, though I find them to be nonetheless effective in supporting me with my nutritional goals.
I’ll write separately at greater length about these goals but in short I aim to keep up the following:
- No biscuits, cakes, sweets, chocolates, dessert, drinks or anything else with over about 5% added sugar. The goal to is to consume the absolute bare minimum added sugar.
- Intermittent fast for 18 hours a day, 5 days a week.
- Eat the healthiest options available to me wherever I happen to be eating.
- Eat pescatarian when it’s available and meat on maximum of 1 day per week, although preferably less.
…apart from on Cheat Day when anything goes.
Why Do I Do a Cheat Day?
Apart from the obvious answer, which is that it is a chance to eat my favourite bad foods, I do Cheat Days because I find that having done one helps me stick to my healthy regime for the other 6 days of the week. For the first few days of the week I don’t have a taste for my cheat foods and towards the end of the week, the looking forward to them gets me over any temptation. I should be clear that Cheat Day for me begins at lunchtime and ends at bed-time, as I’ll not break my intermittent fast until lunchtime, even on Cheat Day.
What’s a Cheat Day for me?
For example, my most recent Cheat Day, last Friday, involved the following, my current favourites:

My main advice with regards to Cheat Day is to do it intentionally. Get in the best treats you truly enjoy. Spend a bit to get the really nice options. That way you are getting the rewards for your hard work for the remainder of the week and are more likely to stick to your goals in the long term.
I did Intermittent fasting for 18 hours a day, 7 days a week. I kept it up for about five years but my family decided I was being too weird so I stopped doing it on weekend when they could see what I was doing. I continued on a 5 days a week basis until I was forced to work at home due to COVID restrictions. With my family now viewing my eating habits 7 days a week, I stopped.
Hi, thanks for sharing your experience. Fasting is certainly viewed by some as an extreme approach and I think it’ll naturally take time for everyone to progress on the journey towards understanding and accepting it for what it is, a positive choice to get and stay healthier!