The Extreme Dieting Regimen That Self-Help Guru Tim Ferriss Uses To Stay Lean

Tim Ferriss, author of "The 4-Hour Workweek" and "Tribe of Mentors," is a firm believer in ketogenic diets and fasting. Here's why he believes so firmly in it. The following is a transcript of the video.

Disclaimer: Tim Ferriss is not a doctor. Please seek medical supervision before attempting to go on a fast.

Tim Ferriss: My name is Tim Ferriss, angel investor and author of books including "The 4-Hour Workweek" and the latest, "Tribe of Mentors." 

Fasting is of interest to me for medical use. For instance, there are a number of cancer researchers who will do extended fasts. Meaning 5 to 7 days several times per year to purge pre-cancerous cells in the body, which are not problematic necessarily in and of themselves unless they then start to grow out of control. And by limiting your glucose intake, whether through a ketogenic diet for instance or jump-starting ketosis and staying in ketosis through fasting, some people believe that there are benefits to that.

And I certainly see, as someone who suffered from Lyme disease, some very, very clear cognitive benefits from entering a state of ketosis, which you can do through a diet. And you think of blood sugar that is often the preferred fuel for your brain and so on. But once you run out of carbohydrates that you've stored, that's when you start to use that fat that we're so good at storing.  And fat can be broken down, with the assistance of the liver, into an alternative fuel source called ketones. So when you are in a "ketotic state," when you are generating ketones, that is called "ketosis." And you can get there through, say, fasting. You can also get there through eating a diet that is very high in fat called, "the ketogenic," meaning producing, "genic —  genesis" ketogenic diet.

But fasting to me has become a routine part of my month. I do a three-day contiguous fast every month and then I do longer fasts throughout the year with supervision. And I'm doing blood tracking regularly so that I know exactly where my glucose levels and Ketone levels, as measured by BHB, are by using finger pricks.

But, suffice to say, don't try it at home without professional supervision.

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[liamf]

I just recently finished a fast for a little over 3 days as an experiment. First two days, was hungry af, and still hungry but slightly less during 3rd day. I roughly measured ketone levels with ketone test strips that you piss on. I wanted to see what this state of ketosis was like. I believe I had slightly more willpower, but can't precisely describe any major changes. I did feel slightly different. I definitely want to try it again in the future and I think next time my body will be more used to the adjustment. If you think about it, many of us have never gone 2 or even 1 day without food. This was not how how ancestors evolved.

[hodoprime]

I’m going to give my unprofessional opinion and say you don’t need to pay a professional to skip a meal or two sometimes.

[prettyprudent]

The longest fast I’ve done was 14 days (three 32oz. bottles of water per day). Reactions can vary dramatically. But when you finally eat, it’s as though everything comes back to life.

[JasonGastrich]

I have fasted a lot and I intend on writing a book on the discipline. I am doing eight months of roughly two weeks on organic food and two weeks of fasting each month and this is month #2.

[KhaledTheSaudiHawkII]

I went on ketogenic diet with intermittent fasting for 3 weeks. Sub 50g carbs, high fat, high veggies. I lost 14lbs, and toward the end l was losing half a pound a day. First two days l had what the call it “ketogenic flu.” Extreme hunger, bad mood, headache, low energy, craving every pizza l had tried in my life...etc. I woke up on the third day feeling much better. On the fourth day onward l never felt hungry, my energy level and mood stabilized and all the cravings were gone.

After two weeks, l started to get cardiac symptoms. When l stood up l’d feel dizzy and my heart would beat really fast. I got very worried and l ended it after 20 days.

Be careful how you end it. On the day l decided to end it, l had a very big meal. I felt l was gonna die. You should reintroduce food especially carbs to your system really slowly.

[Dmien]

It is not extreme it only looks extreme because we have so much of junk out there, too much sugary products, salty products, too much, insane!!

[evanfetro]

I have diabetes and keto-acidosis I am pretty sure is a very stupid way to lose weight. it works though, i lost arount 5-10 pounds before diagnosis but ketones are hard on your body to if you decide to do this kind of diet drink tons of water please

[ninjaraph]

I'm sure Atkins agrees with the high fat low carb ketotic diet. Eat healthy.

[CrystalThatKid]

Lol skipping meals when you're rich (fasting)