Doctor Mike On Diets: Intermittent Fasting | Diet Review
– I've seen your request,
I've read your comments so here we go, intermittent fasting. – I am dying to talk to you about this. – I eat for eight hours,
and I fast for 16. – I can feel the difference. – Before we get into the pros and cons, and if you should do it, let's talk about what
intermittent fasting actually is. Human fasting is not a
new concept by any means. Humans have been doing it for a millennia. Intermittent fasting is just a rebranding of something that we
have already been doing. Our bodies enter a fasting
state every time we're asleep. Some people do intermittent
fasting and not even know it. I mean, there's plenty of times where I had a stressful rotation
in medical school, or a difficult job in the hospital, where I didn't have time to eat breakfast. That's a form of intermittent fasting and our bodies are totally
capable of handling this.
I know what you're thinking. I don't want to starve
myself for health benefits. Intermittent fasting is not starving. When you are fasting, your
body is using stored nutrients and stored energy forms in order to make your body continue to function. When you're starving, you've run out of those energy sources and are breaking down
vital tissues like organs to get that same energy. There are many different
ways to go about going on one of these diets and that
not only makes it confusing for you, but that also
makes it very difficult to do research on it to find
out how effective it truly is because if there are
multiple ways to do it, we have to be able to test
each one of those ways.
The 16/8 diet which is not eating during 16 hours of the day. Alternate day fasting
where you eat one day, fast the other day. 5:2 where two days of the
week that you're fasting. There's no hard and fast rule saying that this is the correct way of doing it. You may be wondering how
is IF beneficial to me? There's been a lot of
proposed health benefits, many of them have been
proven within animal studies or lab models which is not the same thing as being proven in a human model.
But they are very promising. Now, those benefits include
increased mental sharpness, a favorable hormonal profile, weight loss, decreases of inflammation within the body, decreases of certain
diseases within the body. How can IF help you lose weight? You have an increase in growth hormone, a decrease in insulin, and that alone will help you lose weight. Next, because you're skipping meals or you're even going days
without eating meals, it is very likely that when
you look throughout the week, you'll be eating fewer calories. Our thinking is that during
eight hours you'll eat less than you would if you were
eating during 16 hours. Let's talk about these
other health benefits. We know that chronic stress
is not good for the body. The body is just not meant to
be chronically stressed out. It's not meant to have a high heart rate, high blood pressure. Intermittent fasting is really a form acute, short-term, mild stress. This time of acute, short-term stress is really good for the body. What can we use as a metaphor here? Let's take exercise.
Exercise is a form of acute, mild stress. What happens after exercise? We have benefits for the brain, we have benefits for weight loss, we have benefits for disease prevention. Now similarly, when you stress your body through intermittent fasting,
there are some benefits. More autophagy, which is the
removal of cellular waste, more production of neurotropic factors, which protect your brain. And a favorable hormonal profile with increases in human growth
hormone and norepinephrine. Let's talk about some of
the shortcoming of IF. Primarily, there's not enough guidance of what you should eat. We don't know how many calories, we don't know what foods
to eat on the days or times that you actually are eating. Second, we don't know
which form of IF is best.
Third, there are some side
effects when you are fasting that people do experience:
headaches, mental fog, heartburn, these things do exist,
it's not totally benign. Four, we don't know the consequences of following an intermittent
fasting diet long term. Most, if not all, of these studies are done on the short term. If you are eating a very unhealthy diet and then make a change you're
definitely gonna see a benefit But now does this benefit
still hold up one, two, three, 10 years down the line? We don't know that yet
when it comes to IF. And five, it's not easy for everybody to fight off those
cravings on fasting days. All righty, my final take on IF, I think it is a great concept with some really promising
medical research behind it.
I think that if you can skip a meal, you can skip a breakfast here and there, you're gonna see some benefits. Does that mean you should
go on this very rigid diet where you're doing the five
and two or 16 and eight? I don't think we should
quite make this a religious, rigorous part of our everyday life because we don't know the
long term consequences of it. But in a society that
is prone to overeating, a fasting day won't hurt
and will probably help. As always, stay happy and healthy. So here we go, intermittent fasting: kind of ate the word intermittent,
it was like borderline. Our bodies have adapted to
this sort of fasting period because of throughout the millennia, blah, (growling) May people are doing this already and not not…
Our bodies are totally
capable and have adapted to not being filled with
food 24 hours of the day. (laughing) Why are you laughing? Creating more mitochondria which is the energy making
machinery of the cell. Energy making? Which is the energy
center of the sill, sill? (exhales) (laughing) (peaceful music).
