OMAD Diet: What Happens to Your Body When You Fast for 23 Hours a Day?
– All right, Dr. Fung, you are up. So you say eating nearly
2000 calories in one sitting isn't that bad if someone
is on the OMAD diet. So tell us more. – These concerns about
intermittent fasting, to me, seem a little bit misplaced, because it's not something
that we just came up with like in 2021. I mean, Dr. Kahn mentioned Mark Mattson. Dr. Mattson reviewed in the New England Journal of
Medicine in December, 2019, and he had no concerns about that. In fact, and I quote here, he says, "Intermittent fasting
improves multiple markers of cardiovascular health, including blood pressure and cholesterol". And not only that, but
he goes on to point out that, hey, it may play a role in reversing or preventing cancer, Alzheimer's disease, Parkinson's disease, multiple sclerosis, not
to mention weight loss and type two diabetes.
So we know what happens. When you don't eat, your
insulin levels go down, which acts as a diuretic,
you start to pee out. Your blood pressure
actually tends to fall. You lose salted water. And at the same time, other hormones, such as growth hormone go
up, your epinephrin goes up, you activate the
sympathetic nervous system, so your body is actually
being flooded with energy. And that's why people can lose weight, because their metabolic
rate is being maintained. You think of the hungry wolf. That wolf who hasn't
eaten, he's locked in, he's able to concentrate, he's got a lot of energy,
and the metabolic rate is up. So that's a protective mechanism. When we don't have anything to eat, our body actually
switches to using body fat and our blood sugar,
that gives us more energy so that we can go out and hunt. After all, that's exactly
the reason we carry body fat. It's a store of food calories. And if we don't have anything
to eat, we access that.
– Well, there's no debate
amongst the three of us that there are roles for
fasting promote health. The details are the difference. And this isn't a fasting diet. This is fasting/gorging,
fasting/gorging, within one hour, which has been shown in
animal and human models to induce insulin resistance. Fancy term, but your liver
is not functioning well and your muscles in
handling blood glucose, LDL, blood pressure, it's a bad rap.
Now the diet just
described has been quoted by Dr. Valter Longo, professor at USC. Eat a high fat, high protein
diet to promote cancer. It'll take you a decade. I don't want to look good
until I get chemotherapy. I don't want chemotherapy. Finally, it's beautiful
to talk about autophagy. Ask what blood tests any three of us do to actually define autophagy. Unknown, you can't measure it. It's all whoo. I won't recommend whoo to my patients. I recommend fruits, vegetables,
whole grains and legumes, with modest animal products if they wish, patterned after the Mediterranean diet, which is the only place
you can gravitate to and be a legitimate nutrition expert. Sorry, everything else is vanity. – Got it. – Dr. Kahn, I'm just curious. What's your thought on how
our ancestors ate though? Cause you go back a million
years or 100,000 years, they weren't eating, they
were eating a meat-based diet, and they would eat once
a day if they were lucky, they had a hunt it up.
– (garbled) smartphone and
Google those questions, and realize I'm not an ancestral eater, because I'm living with
wifi and stress and microbes that didn't exist. I think it's a fallacy to say, "Pattern after people that
have an average life span of 35 years". You want to look good and live long. I'm 11 years older than you. I want to look good and live
long, but I'm going to do it in a way consistent with the literature. Can we learn from our ancestors? Of course. I would go to the Daniel
fast in the book of Daniel, and eating waters and
(indistinct) produce good results. It's actually been studied
at the University of Memphis in Tennessee, and actually
does produce good results..
