You are here

Does Intermittent Fasting Lead to Sustained Weight Loss?


There are not many things in life you can count on, but unfortunately one thing you can is that there will always be another “diet” book on the market. The latest to fly off the bookshelves in the U.K. promising quick and easy weight loss is The Fast Diet by Michael Mosley, a British physician. The whole premise of his book is that you can lose weight by eating your normal diet five days a week and eating a quarter of that (approximately 500 calories a day for a woman) the other two days.

I don’t know about you, but soon as I see the word “fast,” my hair raises. According to the New Oxford American Dictionary, 3rd Edition, the verb "fast" means to deprive somebody of food. In my opinion, the word "deprive" when it comes to a diet should really be a code word for failure. Sure you will lose weight—because whenever you severely restrict calories you do—but is it sustainable? I say no.

Dr. Mosley claims his entire theory on intermittent fasting and weight loss can be substantiated by clinical research. I won’t argue with that. But I will argue about the long-term success rate. This is what bothers me the most:

  1. How can you guarantee that someone will not start to eat more than his or her “usual” diet on the five days of non-fasting? Because if they do, I am sure the weight loss will stall.
  2. Even one day of too few calories causes most people to get very irritable and fatigued; try being successful at work, at the gym, or in a relationship on those days.
  3. What is a person learning about how to eat healthy? For example, if their “normal” diet is very limited in fruits and veggies, are they being taught how to include them more often? Are they being taught about portion control?
  4. Americans (I don’t know about the British) tend to think more is better. So will someone start to fast for three days to speed a long his or her weight loss? If so, now the risks of nutritional deficiencies start to increase.

Let’s hope the rage of this new diet stays with the author…in England.


Add a comment