Contributed by Jean Claude Vacassin:
The Fasting Diet is a hot topic in the health and fitness media at the moment and it’s something I’m getting asked a lot about, so here’s a brief insight into some of the approaches and their effectiveness.
There are many approaches to fasting. There are true fasting approaches like the lemon and honey detoxes (five to fourteen days with nothing else), juices cleanses (typically three to seven days with fruit juices only – sometimes vegetable), alternate day fasting (a low calorie or ‘fasting’ day followed by a regular eating day), the 5:2 diet (five days of normal eating followed by two days of low calorie ‘fasting’), an 8 hour intermittent fasting window (typically eating between the hours of 12pm-8pm and fasting for the other 16hrs), a 4 hour fasting windows (typically eating between 4pm-8pm), carb back-loading (two big meals daily separating carbs and fats), the Warrior Diet (one large evening meal) and so on. As you can see, there is plenty of choice when it comes to fasting with each approach claiming effectiveness.
Now, the point of this post if not to delve into the science of each approach or it’s specific pros and cons, but rather provide a practical guide as to why and what I’ve seen work best in practice, based on my own experience and the experience of our members at W10 Performance. I’ve experimented with fasting extensively for the last eighteen months and have seen both the good and the bad first hand with the wide range of people I work with.
Fasting appeals to people for lots of reasons. It’s easy to implement, less time consuming, it gives the digestive system an often much needed rest (perhaps key to improving health for most), people eat less overall (calorie reduction will lead to weight loss and has been shown to increase life span), and it very often takes away the seemingly bewildering issue of breakfast preparation! However, fasting also has its potential downsides.
I would nearly never recommend fasting for performance athletes or those who were looking to build muscle. It’s difficult to train full throttle when you are fasting and the reduction of growth hormone production (which has been linked to extending life) would be less than ideal for those looking to build muscle – which to be honest is most people, men and women. That said, I am not totally against fasting for some people and I have seen people get great results and feel much better as a result of following a modified fasting programme.
My view on honey and lemon detoxes and juice cleanses is that they’re not a good idea. Anyone who knows a bit about liver detoxification will tell you that any ‘detox’ that does not include protein is a physiologically flawed one. I’m also particularly anti fruit juice based cleansing as it makes no sense to me to try and regenerate the digestive system by shoveling sugar down your throat…
Outside of these extreme programmes most fasting approaches will work, assuming that people stick to what I would consider clean foods (see our W10 Food Pyramid). My experience however is that people reward themselves for periods of fasting by allowing themselves to gorge on whatever foods they like in their ‘feeding’ windows. And whilst this might (or might not) work for body composition purposes, I’m still in the ‘clean foods equals good health’ camp and would not recommend excessive grains, processed foods, sugar and so on to anybody.
Overall my experience is that people do better with breakfast, so I’m a breakfast man and I recommend that those who can eat breakfast do. But for those who want to give fasting a go, my fasting method of choice for most people would be the 8 hour intermittent fasting method. You’ve got options here but I’d stick to a window of eating between 12pm – 8pm, eating at say 12pm, 3.30pm and 7.30pm. You don’t need to count calories, just stick to clean foods and eat according to appetite initially. Most people will eat less by default because their meals will be closer together and portion sizes will therefore be smaller. I would add to this a green drink first thing and/or throughout the morning and some amino acids (protein) first thing to help with immune function and detox. This will work well for most.
The approach that I’ve had least success with are the alternate day fasting approach and the 5:2 diet. Both seem to work well initially but longer term they leave people hungry, are very difficult to maintain over the weekend (this is a real issue for a lot of people) and they are hard to keep up. If you do chose to go down these routes, the best way to stick to the alternate day method is to ensure that you exercise on the normal eating days and that you do not exercise on the low calorie days.
NB: The Warrior Diet and Carb Back-loading work (certainly short term), but they work best for people (mainly men) who are already pretty dialed in with their eating and exercise habits and who are looking to maximize muscle mass.
Jean Claude Vacassin, is a father of one and the owner as well as a personal trainer at W10 Performance in Notting Hill—a fitness facility that takes a holistic approach to getting you long lasting results.
