Intermittent Fasting 101

Intermittent fasting is what you’ve been looking for?

Anthropologically speaking, intermittent fasting doesn’t make sense. Willingly abstaining from food for a set period of time (intermittent fasting) would have dumbfounded our ancestors. However, evolutionarily the environment we live in today is novel and necessitates such changes…

Intermittent Fasting 101

Novel in the sense we are a prime example of an environmental mismatch because we did not evolve in an environment of surplus energy (food).

Thousands of years ago, in order to take in energy (food), energy had to be expended (hunt, gathered, etc).

McDonald’s did not exist around the corner to consume 5000 calories whenever you felt hungry. Because our DNA evolved in an environment where food was rare, in order to ensure survival, we are predisposed to overeat as often as possible.

Intermittent Fasting

Couple our inherent biological predisposition to overeat with an environment of surplus food that consists of an immense abundance of fatty and sugary foods (which we are also predisposed to favor) and you have a health disaster or a recipe for an obesity epidemic which is clearly steadily on the rise.

Humans can either be in a fed or fasted state where we either are storing the energy we just took in or we are using our own energy reserves (fat, muscle glycogen) to fuel our bodies. In the environment we were designed for, there would be a natural balance to our energy equation.

We would eat, store some of that energy, and then in the midst of trying to acquire more energy, burn off whatever we just stored. Hunter-gatherers were and are lean because of this inherent reason. The problem with the Y2K diet, credit to Nate Miyaki for that term, is that because of our evolutionary predisposition to constantly seek food, most humans spend as many as 20 hours a day in the fed state.

When you spend a disproportionate amount of time in the fed state, you never allow your body to burn fat for energy and obesity results.

In short, that is the reason why I believe intermittent fasting as a way of life, not a diet, can be incredibly effective in managing our environmental mismatch. In the 21st century, it’s too difficult to consciously maintain a caloric deficit over a long period of time.

Over time, we eventually fall back into our own biological tendencies and begin overeating at a rate that our bodies can’t handle. Intermittent fasting can circumvent this biological tendency by setting aside a given time every day or week to being in the fasted state, ensuring a caloric deficit (the most important part of fat loss).

The problem is that dieters often suffer from information overload and that is no different with intermittent fasting. Within the intermittent fasting community, there are three main methodologies to consider:

“Leangains” Method:

Made popular but scientifically butchered by The 8 Hour Diet. It is a methodology that for women involves daily fasts of 14 hours coupled with a 10-hour eating window. Unlike what The 8 Hour Diet popularized, daily fasting is not a prescription to eat whatever you want within that time period. The Leangains method couples daily fasting with planned carb and calorie cycling.

Though meticulous initially, I believe this plan could result in the most dramatic body recompositions of the three main schools of thought.

24 Hour Fasts:

Brad Pilon in Eat Stop Eat popularized the concept of weekly 24-hour fasts. In theory, it is the simplest as you literally fast for 24 hours once or twice a week.

Because you are spending an extended time in the fasted state, altering your diet isn’t inherently necessary (though recommended) because the caloric deficit is already created.

Though it doesn’t require any intricate rules so common in modern diets, 24 hours can be a long time and some may not respond well to prolonged fasting of this duration (women have lower fasting plasma glucose levels so maintaining a longer fast for some can be problematic). It varies on a case-by-case basis.

5:2 IF:

Popularized by The FastDiet this past year. It is a methodology where for five days throughout the week you eat as you normally would, but for the remaining two days, you would consume 500 calories daily. This plan is perfect for the more relaxed dieter who doesn’t want the extreme 24-hour fasts nor the planning involved in the Leangains method.

All three plans can work and work quite well. The most important aspect for you is finding something that is sustainable long term.

Sustainable in the sense that you don’t lose twenty pounds to subsequently gain thirty back. This is the sole reason why most diets fail in the long term because it’s exactly that a diet, not a permanent lifestyle change.

Diets don’t work that’s why there are new bestsellers being continually written each year.

Here are some tips going forward:

1) Understand that intermittent fasting isn’t a magic pill. Magic pills don’t exist in diets or in life. What intermittent fasting can be is a framework that can put you in a better position to combat our evolutionary tendencies that make staying healthy and in shape so difficult.

2) Give it some time. I’m going, to be honest, the first time you try any of the above methodologies it is not going to be easy. It takes time for your body to adjust so don’t be scared off if the first couple of fasts don’t go as smooth as you had hoped. However, if this continues past the initial adjustment period, fasting may physiologically not be right for you.

3) Food choices still are the most important thing. Even if you only eat in a 10-hour window a day, if you create a caloric surplus, you will gain weight. The Y2K diet is never a recipe for sustainable long-term success.

4) Be careful of information overload regarding fasting. Everyone is trying to take advantage of the boom in popularity of IF so be careful who you trust for sources. There are plenty of good ones out there including the names I already mentioned (Berkhan, Pilon), myself, and others such as Mark Sisson and Nate Miyaki to name a few.

Follow one of their methodologies, give it a chance, and if it doesn’t work out move on to someone else but I warn you to try and blend theories and practices because it’ll prove too difficult for you to realize what worked and how to tinker it to continue your progression.


If you are looking for a good resource on a good beginner resource for intermittent fasting, I do recommend checking out my books, Fat Loss 101: Intermittent Fasting Simplified or Turn On Your Skinny Gene: Fasting For Women both available on Amazon.

Happy Fasting!

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