Physiological Changes That Occur During Fasting

Fasting provides incredible physiological changes that span far beyond fat loss. In this video, Dr. John Jaquish explains the benefits of fasting, including lowered insulin sensitivity, HGH upregulation, and T-cell regeneration.
Full Transcript

I mention this all the time: the longer the fasted period, the greater the benefits. But I say that generically, and I don’t think people have the vision of the different steps and how long they take to get to. So the real benefits of fasting start at 12 hours. Now, somebody who may just skip breakfast and do 16:8 fasting, may get just one or two hours of benefit out of this. This is usually when your body starts switching away from glucose as a fuel source and moving to fat storage. This is the process of ketosis.

By the way, there’s no such thing as a ketogenic diet per se. Ketogenesis is a function of the human body. So when somebody says, “Oh, keto is not really a thing,” it’s like, “Yeah, it’s a function of the human body.” That’s like saying your liver is not a thing. It’s real, and it’s there.

Just as a side note, for those who are looking at when ketosis begins, there’s a variance and sort of an overlap where ketosis becomes its strongest. That’s really at the 24-hour mark. 24 hours, that’s when autophagy starts. So you got to keep in mind that people that talk about autophagy and just do one meal a day, they might only be getting like one hour of cellular recycling.

I encourage everybody to experiment, to go longer, 36 or even 48 hours, just two days with no food, and then your body will start to recycle.

Now the lighting’s probably not right for me to show you in this situation, but most of you have noticed I have a brand of my fraternity letters. It’s been there since I was first elected president of my fraternity in undergrad, and that’s been a while. That brand was high, you could see it right through my shirt. It had a thick keloid-type scar over the branding. Now, since I started going into autophagy with these longer fasts, my body has been eating it from the inside and that scarring is almost gone.

So you want to look at that as a transition, which is, while the body’s transitioning, you might not feel great the first few times you do it. So just a warning: don’t try this once and say, “Well, I didn’t feel good, so I don’t really want to do this anymore.”

You really got to give it a number of chances, and ultimately you will feel fantastic when you go through that first 24 hour period with no food, which is really why I like one meal a day. I think that makes sense with human physiology. It makes sense to have meals with your family.

Now, at 48 hours, some really dynamite benefits start to happen. We start seeing massive changes in growth hormone, and that will also amplify your workout. So if you work out, fasted, and you have the stabilizing mechanisms that I talk about in some of the other videos and I discuss in the book, you’re going to have an even higher growth hormone level.

So at 50 hours fasted, you get an insulin effect that’s very noticeable. The insulin gets as low as it can possibly go, and you’re just really optimized to continue burning body fat. Also, when you start eating again, it’s just a very tiny amount of carbohydrates will be like rocket fuel for you into your workout, which is where the hyperplasia protocol really gets amplified.

Now, I realize 50 hours is a long time, you got to work up to that, but the reward is there.

Now, here’s something even more exciting. And this I did multiple times and I do multiple times, especially when viruses and pathogens are going around and people are getting sick, I do a 72 hour fast. And in 72 hours, your body completely replaces its T-cells. So complete renewal of your immune system. This is absolutely fantastic and I absolutely recommend it, even just for that alone. Just such an unbelievable feature of that 72 hour fast.

Now, past 72 hours, there’s not a lot of research because maybe there’s not a lot of volunteers or maybe it just hasn’t been researched because researchers aren’t sure that there’s really a benefit out there, or maybe they’re not sure that people are willing to do that, which is probably also likely.

However, there was a study done in 2018 by Anton and researchers talking about flipping the metabolic switch and it goes over a multitude of different benefits over periods of time, and anybody that wants to do a deeper dive on this, I recommend that study.