by Deric D’Agostino, D.C.
I started doing some fasting when I started the keto diet. It was pretty interesting. We all fast anyway—from when you eat dinner at night, you end up breaking the fast when you eat breakfast. That’s where the word breakfast came from—to break the nightly fast. Usually most of us fast for about 12 hours while we sleep.
There is a thing called intermittent fasting, which just prolongs your fast a few more hours. So, instead of eating at 8 am when you wake up, you push that out to 1 pm. A common intermittent fast is 16/8; 16 hour fast and then you eat your total calories in a 6 hour window—say from 1 pm to 7 pm.
I tend to do 24-hour fasts throughout the week. Monday thru Friday, I will eat when I get home at 7 pm. Back in the day when we were hunters and gatherers, we may have gone three days or more without eating.
Fasting and insulin
When we eat the typical American diet of heavy carbs and high sugars, that increases insulin and stops all fat loss. After 6-12 hours of fasting, depending on how insulin resistant we are and depending on our general makeup, we start to tap into our fat stores—meaning, we start burning fat for energy. The excess sugar is consumed by the body over that time frame and insulin is low since you haven’t eaten. Intermittent fasting thus extends your fat burning time frame.
Fasting and growth hormones
There are many benefits from fasting. One big benefit is a surge in human growth hormone (HGH) that burns fat and increases muscle mass. After all, if we didn’t eat for two days we would need muscle and energy to chase down an elk so we could eat.
Growth hormones are usually secreted while we’re asleep (fasting), released very quickly just before waking to get our body ready for the day. They take some of that glucose from storage and pushes it into the blood to be used for energy. That’s all the energy fuel you need for the day—breakfast isn’t even necessary. Ever wonder why we don’t usually really feel like eating anything in the morning and only take our coffee? It’s that growth hormone doing its work.
Breaking the eating habit
Another important lesson I’ve learned is breaking the eating habit. How many times have you said, “It’s 12 noon, I’ve got to eat!” You really don’t. I have found that I can quite comfortably fast for 24 hours with no real problem. I have even thought about extending that fast to 30 or even 40 hours. But as I am sure you have guessed, I haven’t broken that habit of coming home from work and eating because that is what I have done for the last 50 years of my life. During the day, I may feel some hunger pains that tend to go away after about 10 minutes. But, when I do get busy at work, my energy increases tenfold while fasting.
Another important thing that occurs is what is called autophagy. Autophagy is derived from a Greek word that essentially means “self eating.” When we are fasting, insulin production stops and glucagon increases. Glucagon is a hormone produced in the pancreas. It works to raise the concentration of glucose and fatty acids in the bloodstream, and is considered to be the main catabolic hormone of the body. This increase in glucagon stimulates the process of autophagy. The body starts to eat, destroy, and re-cycle the cells of the body that have been damaged or hanging on long after their usefulness in a toxic body. This, is in essence a form of cellular cleansing. The body is an amazing thing when we treat it like we are supposed to—good things happen!