Fasting: What it is, Why to try it

After you read this, see Fasting: How to do a 24-hour fast

A fast is a food-free interval. Remember, it’s not about not eating. It’s about eating at a predefined time. This kind of “intermittent fasting” is a good tool to learn what’s going on in your body and how to control it. It should not be arduous.

Intermittent fasting: What it is
Let’s be clear:

  • Fasting means voluntarily abstaining from all food for a discrete period of time that you have decided in advance.
  • Fasting is “not eating until (insert specific time decided in advance).” When you fast mindfully, you learn to eat with punctuation. Proper punctuation. Fasting is not a full stop or period. Fasting is a pause or comma. Normal eating for human beings involves fasting or meals. We eat, pause, eat.
  • We are talking here about occasional, intermittent mini-fasts (for 24 hours or less) for health and awareness.
  • This post applies to a 24-hour mini-fast, which is what I recommend to most people. Almost anyone can fast safely for 24 hours. Do this no more than once a week. (Some people may wish to start by experimenting with even shorter fasts of four to eight hours, but this is not necessary.)

Intermittent fasting: What it isn’t
It has been my experience that the biggest problem with fasting is that people have a lot of pre-conceived ideas. To clarify:

  • Fasting is not impulsively skipping a meal, which is destructive to your weight regulating mechanism and often ends in overeating later.
  • Fasting isn’t dieting, especially not a crash diet to fit into your favorite outfit.
  • Fasting should never be motivated by peer pressure or desperation. If you’re not interested or ready, try something else. If you’re curious, give fasting a try. Your fast should be motivated by confidence and the wish to master eating skills.
  • Fasting is not dangerous, unhealthy or a miracle cure. Fasting does not require drinking nasty-tasting cleansing supplements.
  • This is not about fasting for spiritual purification, detoxification, or extreme and rapid weight loss (which is really starvation).
  • After being baptized, Jesus went into the desert and fasted 40 days and nights (Mat 4:1-2). In 1943, Mahatma Gandhi fasted 21 days to stop Hindu-Muslim violence. You are not them. I’m suggesting you consider a mini-fast of up to 24 hours. You don’t even have to go a single day without a meal.

Benefits of fasting
Fasting has many benefits:

  • It jump starts your learning to master the fundamental skills of eating and develop better lifelong eating habits.
  • Almost everyone tells me that fasting is very empowering.
  • It doesn’t cost a penny. Fasting is free. You don’t need to buy supplements or services. If you’d like to buy a book, I recommend Brad Pilon’s Eat, Stop, Eat.
  • Fasting teaches your brain to trust you. The reptilian, survival part of your brain is a beast. The way to tame the beast is to feed him regularly and predictably. If the beast is reassured that there will be food coming, he will be soothed and not bother you. If you constantly insist on traumatizing yourself with random restrictive diet plans and negative threats about not eating, the beast gets upset. Fasting is about building a trusting relationship with the beast. If you promise the beast he will have a meal tomorrow exactly 24 hours from now, and then ALWAYS deliver that meal, he will be begin to trust you.
  • It develops mindful eating. Brian Wansink wrote the phenomenal book Mindless Eating. He notes that we make thousands of eating behavior decisions every day, but are usually aware of only a handful.
  • It reduces your insulin resistance.
  • It helps you avoid snacking. Once you experience that a 24-hour pause in your eating is perfectly tolerable, it becomes easier to avoid snacking. Frequent snacking or perma-grazing starts to seem ridiculous.

Tips for success
Let’s talk about how to succeed:

  • You have probably already fasted successfully. On orders from doctors like me, you have probably fasted before a medical test or surgery. When you had to do it, you just did it. When I was a practicing physician, I ordered thousands of patients to fast successfully.
  • Many other people just like you have successfully completed mini-fasts of 24 hours.
  • You are the boss. Fast to gain will power, not to lose weight. Fast to improve awareness of your eating habits. As you fast, see how often you have thoughts of eating. Fasting should make you feel like you can decide when you’ll eat again and then stick to it.
  • A failed fast is just a learning experience. If you eat during a fast, end it immediately. Try again next week or when you are ready. When I experimented with fasting, I tried to do it every Friday for several months. Some fasts went well, some went crappy. I learned a lot from both.

Fasting is safe
Almost anybody can safely do the kind of 24-hour mini-fast I describe here. We have plenty of stored body fat. I recommend women not fast longer than 24 hours. Diabetics should not fast, even short fasts, unless under a doctor’s direct supervision.

When I had an active medical practice, I fasted thousands of patients. As a species, human beings survived because we are physiologically designed to survive fasting for many days, even weeks, when there is nothing to eat. That does not mean you should fast for days or weeks.

But won’t I be hungry?
Of course. Hunger is a signal from your brain urging you to eat. Just because you are hungry doesn’t mean you’re starving. If your brain thinks it can nag you into eating, it will. When your brain is convinced you mean business, and it is reassured that at some reasonable time in the future there will be food (predictability), then your brain will often leave you alone for a while.

How it works: Fed state and fasted state
While you are fasting, which means not eating for a specific period of time, your blood sugar will slowly drop. As long as there is short-term fuel in the muscles and liver, the body will preferentially use this. Even though you may feel hungry, your body is still in the fed state.

When you enter the fasted state depends on how much you ate. For a snack or a very low calorie meal this may be 2 or 3 hours. After a very large meal, it could be 10 hours. Usually, it’s about 6 hours after a meal. It’s important to remember that not only is each meal different—you are also always different. From hour to hour and week to week, we vary our activity, sleep and stress levels.

As you approach the fasted state, you have a choice. If you keep topping off, you will always be in the fed state. This is fine if you are happy with the amount of body fat you are currently carrying around. This is maintenance. However, if you want to release fat so that it can be burned as fuel, the body must be in the fasted state. You don’t lose weight, you use weight. If you want to be “less fat,” you have to use fat for fuel. If you want to use fat for fuel, it must be released from the fat stores. Fat stores are guarded by insulin. When you are in the fed state you will always have insulin around. Insulin will not allow you to steal his fat. Insulin will either compel you to eat or start breaking down body parts into bits to be used as fuel. You will not get to his fat. To release fat you must make insulin go away. To release fat you must be in the fasted state.

Stop eating like a baby (often)

Eating like baby

Frequent eating — perma-grazing — is not adult behavior and it’s not good for your health.

Many adults eat like babies. Frequent eating is baby eating.

In the womb, the fetus is nourished constantly through the umbilical cord as if on an IV line. Every time I clamped an umbilical cord, I started a human being on his or her first fast. Humans can store food. Babies have to learn how to eat, pause (and during pause, use stored fuel), then eat. It’s a tough adjustment. That is why babies get hungry and cry all the time. As we mature, we should have longer intervals between meals. But many people can’t go from one meal to the next without snacking. They eat like babies.

Frequent eating causes many problems. Frequent eating causes weight gain and other health problems. If you think of the body like a fire, frequent snacking fuels it not with good logs but with kindling – often processed snack foods high in starch and sugar.

Real starvation is different
Fasting for 24 hours doesn’t cause starvation. Real starvation is what happens when there is no spare sugar in the blood, no spare sugar in the muscles or liver, and the fat stores have been released and used up. At that point, the body begins to digest itself. Starvation is involuntary. A small percentage of people, especially women, suffer from a disease called anorexia nervosa that causes compulsive under-eating. That behavior is involuntary and compulsive, not a voluntary fast.

Further info: Brad Pilon
I recommend Brad Pilon, who has written a great book “Eat Stop Eat.” He also has a blog “Eat Blog Eat” about short, simple fasts. He’s on the Food Books and Resources page.

I checked into his resources and felt really comfortable with the data and conclusions. Generally, I find that men are usually willing and able to jump right into testing Pilon’s ideas. Women sometimes want more information, motivation and reassurance before they feel comfortable with the idea of fasting. I think mini-fasts are safe for any healthy person.

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