Nov 24 Alternate Day Fasting For Fat Loss

[Lindsay]

Good info ...

Jade Teta ND, CSCS

Many of our clients ask us about fasting and how that may impact weight loss vs fat loss. I have blogged previously on how years ago I would “fast” (go all day without any food) once or twice a week as an aid to burning fat. This technique has recently gained support among many seeking body change and restored health. This is being promoted as a technique called “alternate day fasting”. The question is can this approach work to burn fat and optimize muscle for long term body change?

It is important to remember that fat loss and weight loss are not the same thing. Weight loss is usually about indiscriminately decreasing calories while fat loss is about manipulating hormones so that you eat less naturally. In general, long-term fasting is not a useful technique to use if you want to burn fat. This is not because it does not work, it is because it is not sustainable for most people. However, under the right circumstances you may be able to use fasting to your advantage. The problem is that many people will simply use this technique in the same way they use other crash diets. They will ignore exercise and food quality and decide to fast to reduce calories. This approach is playing the weight loss game and will likely end up causing you to lose muscle, creating the all too frequent YO-YO effect. In order to use this technique to lose fat and spare muscle, it would be wise to pay attention to food quality, exercise, and supplementation. If you are the type that just wants the skinny on what to do rather than all the details, skip down to the bottom. Otherwise read on to hear metabolic effects take on fasting.

Brief history of fasting

One important thing to understand is that the idea that humans should eat three meals a day, or 6 small meals per day (as many in the fitness industry, including ME, advocate), is a completely made up construct. In other words, it is not actually how we humans evolved. Studies of modern day hunter gatherers suggest humans in natural conditions only ate 1 time per day after gathering or hunting for food all day (1-4). There was no breakfast, no lunch and rare snacking. I point this out because it is an often neglected insight in understanding the natural eating habits our metabolisms evolved with. Another important point is that food was not always available and there were likely days where much less food was consumed. So the idea that food was eaten everyday, is also wrong. Our physiology evolved under feast and famine circumstances and even when food was available we had to work to get it.

Even with these considerations, we must not forget we live in an entirely different time. Food in modern times is easily accessible all day everyday. It is likely true that if early humans were confronted with an environment where food was abundant and easily available without physical effort they would have had eating patterns more in line with what were used to today. The reason I believe, and often recommend, eating 6 small meals a day is because not many people in today’s culture can voluntarily abstain from food. Especially when it is cheap, abundant, tasty and just a walk to the pantry or a trip up the street away. We are programmed through our ancient physiology to eat whenever food is available, and since food is always available, we eat almost constantly. Eating 6 small meals per day of high fiber and protein foods can help us reduce hunger and cravings creating the key elements for fat loss 1) reduced calories and 2) Proper hormone balance. However, there is a way to imitate the fat-loss secrets of our ancestors while avoiding the binging scenarios that often ensue after haphazard fasting. It is called alternate day fasting, intermittent fasting, or night time fasting.

Understanding fasting and how to do it right

The vast majority of people who decide to abstain from food for the day will likely make it to early afternoon or maybe evening before they scarf down a whole pizza or inhale a fast food burger and fries while guzzling down a liter of soda. Once we get hungry and we know food is around all bets are off. The idea of fasting in this way will fail for most of those who try it. There is a better way, but before I talk about that it is important to understand the physiology of fasting. Afterall, body change is about fat loss, not weight loss. Understanding exactly how the body partitions its fuel during fasting is key to doing it right.

During the first six to twenty-four hours of avoiding food, your body will use stored sugar called glycogen (gleye-co-gin). This fuel does not last forever, and once it is gone the body will spend the next two to ten days using amino acids from your muscle tissue to make more sugar for the body. This is not a lucky thing since a loss of muscle means a less efficient metabolism overtime. This may be surprising to some who think fat is the primary fuel during times of fasting. While some fat is being burned, it does not become the primary fuel until after a fast has lasted greater than ten days. Only then will you begin to really ramp up fat loss. This is an ancient survival mechanism of our ancestors that served them well. However, for us it is a liability since long before 10 days have gone by, you will have likely already broken the fast by inhaling large amounts of sweets and/or fatty foods (this is what the body craves after it is deprived).

So, rather than fasts that lasts days or weeks, it is far better to engage in short fasts. Remember within one day of a fast you can begin stripping muscle off of your body which is something you will regret overtime as your body begins to sag. A soft skinny body “skinny fat” is a sure sign of chronic low calorie diets and/or fasting without exercise. I recommend fasting for no longer than 24 hours and doing this no more than three times per week. This technique has been shown to produce the same health effects of low calorie dieting while also giving you the energy and fuel to exercise and maintain muscle mass. However, even one day of fasting is something most people will fail at. That is where 3 techniques come into play:

1) Modified alternate day fasting- In this technique you dont completely abstain from food on your fasting day, but instead only eat 1 meal or maybe a meal and a snack. In other words, the amount of food is still very minimal. This technique works better for most people who dont have an iron will to keep themselves from eating all day, but still want to reap some of the benefits.

2) Using supplements to control hunger and cravings- Another technique is to fast for the whole day but use non-calorie functional foods and supplements to control your hunger, cravings and energy. A fiber supplement taken 3 times a day along with branched chain amino acids (BCAA) and unsweetened cocoa powder in water work great in this way. These items provide zero calories but balance hunger hormones and brain chemistry and work very well to shut off the hunger and craving mechanism that can sabotage any body change program.

3) Night time fasting- Perhaps my favorite variation of alternate day fasting is to give equal time every 24 hour period with and without food. I feel this is an even better option since during the day you eat normally and at night you abstain from eating. The key is to break the day into two 12 hour periods. 12 hours for eating (during the day) and 12 hours for fasting (at night). In this regime, the last meal for most people will come between 6pm and 8pm, while the first meal will come between 6am and 8am. Research has shown this approach works and can provide the same benefit as alternate day fasting. IN my clinic I often adjust the timing of this “overnight” fast to the individual. Usually I prescribe 10 to 14 hours of a “night time” fast.

Why fast in the first place?

You may ask why fast in the first place. The benefits of short term fasting is its ability to reduce your glycogen stores forcing the body to tap into it fat stores more readily when you engage in exercise. The other point about fasting is it is a powerful detoxification mechanism. During times without food, the body can mobilize its resources away from the digestion of food towards repair and regeneration. Finally, short term fasting that lasts less than a day will actually raise HGH levels and re-sensitize the body to its metabolic hormones. When eating resumes the metabolism is far more efficient then it was.

For the fitness enthusiasts who is looking to maximize fat loss and is wants to be optimally healthy, this is a technique to consider. A final warning however is that if done incorrectly (fasting for too long, fasting without weight training, fasting along with excessive aerobic exercise, fasting without adequate protein intake on eating days) the metabolism will suffer. This is not a technique that should entered into lightly.

1. Osgood, C. Ingalik Social Culture. Yale University Press, New Haven, 1958, p 166.

2. Clastres, P. The Guayaki. In: Hunters and Gatherers Today, Bicchieri, M.G. (ed), Holt, Rinehart and Winston, Inc., New York, 1972, p.151.

3. Lee, RB. The !Kung Bushmen of Botswana. In: Hunters and Gatherers Today, Bicchieri, M.G. (ed), Holt, Rinehart and Winston, Inc., New York, 1972, p.151.

4. Lewis ND. The Pacific Islands. In: The Cambridge World History of Food, Volume Two, Kiple, KF. 9ed), Cambridge University Press, New York, 2000, p. 1358.