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Tim Ferriss – 3 Day Fast Protocol Details – Get into Ketosis Quicker and Easier

Tim Ferriss - 3 Day Fast Protocol Details - Get into Ketosis Quicker and Easier

In Tim Ferriss’ book Tools of TitansTim Ferriss - 3 Day Fast Protocol Details - Get into Ketosis Quicker and Easier he puts forward a method to optimize the process of fasting. In his typical 80/20 style, he aims to get the most benefits, in the least amount of time.

His recommended fast is conducted in a 3 day period, spanning Thursday evening to Sunday evening. It is an aggressive protocol, especially if you have never fasted before.

3-Day Fast Overview

  • Stop eating Thursday night
  • Friday morning go for a long walk to accelerate your transition into ketosis
  • Friday and Saturday stay fasted, and consume moderate amounts of exogenous ketones and MCT oil (as needed), to give you a boost while you’re keto adapting.
  • Sunday evening you break the fast.

Here’s the process in more detail if you don’t have Tools of TitansTim Ferriss - 3 Day Fast Protocol Details - Get into Ketosis Quicker and Easier to hand:

Thursday Evening

  • Eat a low carbohydrate dinner around 6pm. Make that the last meal of the day. Go to bed as normal.

Friday Morning

  • Drink some caffeine if needed, then get out the door and walk within 30 minutes of waking.
  • Bring at least 1 litre of water, with some added salt (to prevent headaches/cramping), and sip as you walk.
  • Walk for 3-4 hours(!). Filling up/buying more water as needed.
  • Arrange phone calls for this time, to make the time productive.
  • The idea behind the walk is that you use up your glycogen stores, forcing your body to move quicker into deep ketosis. The quicker you get into ketosis, the less time you spend feeling sub-optimal, and the less potential muscle wastage.

Friday Day (post walk)

  • Consume exogenous ketones or MCT oil 2-3 times throughout the day, where necessary.
  • Tim primarily uses KetoCaNa & KetoForce as exogenous ketone sources. Both these products contain 11.7g of Beta-hydroxybuterate per serving, and each contain 16 servings. The key difference is that KetoForce is an unflavoured (alkaline) liquid. And KetoCaNa is an orange flavoured powder you can mix into water.
  • Dom D’Agostino, a leading authority on ketosis, and one of Tim’s regular podcast guests also users another product called Keygenix PRIME. Its comes in powder form and contains Beta-hydroxybuterate mixed with MCT powder. The mix of ketone salts and MCTs provide both a quick burst of energy, and a longer lasting ketone release. It may be possible to mimic this by taking ketone salts and MCTs together manually.
  • MCT oil covers a range of MCT fractions; C8, C10 & C12. To induce maximum ketone production from MCT oil, you want pure C8 oil (also known as caprylic acid), this can be found in Bulletproof Brain Octane. Keep an eye out for MCT oils that have low levels of C8, and are mostly C10 and C12. Whilst they are technically MCT oils, they won’t raise ketones as well.
  • The intention with these ketone sources is to provide your body and brain energy until your ketone levels elevate naturally. At which point the feelings of hunger will reduce, and you will feel like you have more energy.

Saturday Morning

  • Upon waking, test blood ketones. You are aiming to be at 0.7mmol or greater. Ideally use a ketone blood testing meter like the Precision XtraTim Ferriss - 3 Day Fast Protocol Details - Get into Ketosis Quicker and Easier. Urine testing strips (cheaper option) are not accurate enough.
  • If you’re at 0.7mmol, great, proceed normally with your day.
  • If you’re under, consider going for another extended walk, and then re-test.

Saturday & Sunday Day

  • Add further exogenous ketones or MCT oil if you need a boost. Once you are deep into ketosis they can be omitted.
  • Incorporate some sodium in your water throughout the day. This can either be in the form of himalayan sea salt added to water, or via a specially formulated solution such as SaltStickTim Ferriss - 3 Day Fast Protocol Details - Get into Ketosis Quicker and Easier electrolyte replacement pills.

Sunday Evening

  • You can break your fast. Tim suggests for longer fasts, some care is needed on the re-feed. But for this 3 day fast, it doesn’t matter as much. Eat what you find to eat.

Potential benefits include:

  • Increased autophagy – which amongst other things, plays a vital role in inducing pre cancerous cell death
  • Immune system regeneration
  • Reduced inflammation
  • Increase in neurogenesis (new brain cells)

Tim Ferriss now aims to do this 3 day fast process once per month. With a 5-7 day fast once every 3 months.

If you enjoyed this post, you may also enjoy:

  • Dr Rhonda Patrick’s Preferred Supplement List (article link)
  • Dom D’Agostino’s Cancer Protocol (article link)
  • Rhonda Patrick’s Diet Details – Breakfast, Lunch & Dinner (article link)
  • Tim Ferriss’ Preferred Nootropic Choices (article link)
  • Rhonda Patrick’s Pregnancy + Baby Product Recommendations (article link)
  • Tim Ferriss Supplements – What He Takes and Why (article link)

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    • Great question Michael, and its something I wondered about also. I believe for a 3 day fast, assuming you’re adequately nourished going into the fast, there would be no *need* for a multivitamin. And then for longer, 7+ day fasts it makes absolute sense to add in multivitamins (so as to provide micronutrients that your body can’t synthesize from its fat stores).

      All that being said, I would love to come across more literature on the matter. Last time I checked I didn’t find any studies related to that.

  • Can someone please suggest the health benefits of fasting? And does this need to become a life style. Also, smoking during fasting…. does this throw off your ketosis? Hormones perhaps?

    • Hi Nicole. I’ve summarized some of the core benefits of fasting at the bottom of the post – but there’s lots more info out there on the internet in that regard.
      Regarding smoking, the nicotine shouldn’t have any negative impact on the core aspects of the fast (related to lack of food). You would still eventually hit ketosis and lower your blood glucose. Actually, if you tried to stop eating AND stop smoking, that would probably be a tough combination. Best to keep the smoking and focus on the fasting.
      In terms of does this need to become a lifestlye. There would certainly be benefits to that. But just tackle it one step at a time, and see how you get on with your first few fasts.

  • I used methods like this one before, but nowadays I just fasting (eat/drink nothing but water) for 3 or 5 days and work perfectly, after you adapt to it.

  • I have decidec to try this fast this weekend. I am going to use MCT oil (pure C8 oil) rather than exogenous ketones. So should i consume this only on Friday? And how man times each day should i consume? Also, when i do cesium the MCT oil, how many teaspoons or servings should i take per each time i consume? Hopefully that makes sense.

    • Hey! C8 oil is excellent. Generally you want to use the oil sparingly. Its purpose is to bridge you from burning glucose to burning ketones. Ideally you want to use a blood glucose and ketone meter to measure those levels. You’re ideally look for your blood glucose to dip, and your blood ketones rise. Once they hit a 1:1 ratio you shouldn’t need any more C8 oil.

      Without those tools, just use the C8 oil on the Friday, and possibly Saturday, when you feel you need more energy. Going above 2 tablespoons in a single serving will probably upset your stomach! So be cautious with dosing it.

  • Hi, thanks for sharing!
    I can’t get Mct oil or exogenous keytones in my country, is it ok to consume one table spoon of coconut oil 3 times a day instead of the mct oil 3 times a day? I followed Tim’s fasting exactly during my first fast last month but I substituted the mct oil with cocunut oil a table spoon 3 times a day (couldn’t measure my self to see if I was in ketosis though). Do you think this is not considered a fast or it doesn’t get me to ketosis?

    Thanks in advanced!

    • Hey.
      Yeah I think the coconut oil is a good substitute if you can’t get C8 MCT oil or ketone salts.
      Sometimes we just have to be resourceful!
      As your blood glucose levels drop you will gradually go deeper into ketosis.
      From the 24 hour mark to the 48 hour mark you will be in ketosis. And as you go past the 48 hour mark you can expect your blood ketones to keep increasing.

  • I’m about to do this protocol for the purpose of entering an extended ketosis for the first time. Blood monitoring, the whole deal. My question is: will drinking BCAA’s during the fast slow down or prevent my transition? I’d like to add some AA’s for flavor and muscle sparing during my fast. Thoughts?


    • Hi Jacob, protein (which is made up of mainly amino acids) does have a pathway to convert to glucose. And glucose is basically the key thing you’re trying to avoid spiking (as spiking it drops natural ketone production, and affects a number of other, relevant, pathways).

      BCAA supplements, whilst minor, will stimulate some insulin.

      I would probably suggest only taking them pre-workout (so you can utilise any extra glycogen in the workout), and perhaps do blood measurements before and after to see if glucose has gone up, stayed the same, or gone down.

  • I would imaging that dosages for exogenous ketones and MCT oil will vary based on gender and body weight. Do you have any guidelines or suggested resources on how to adjust amounts based on either physiology or in response to your individual reaction to fasting? E. I. Are there adjustments that you can make in response to headaches?

  • Hi John. I am halfway through but just drinking water. No oils, supplements etc. I presume the net result will be the same?

  • Hi!

    Two questions =)

    1) On Friday should I consume ketones and MCT oil before the walk or only after? Consuming them before might that make it harder to empty glycogen storages?

    2) Can I do my strength training as normal during fast or is there anything special I should think about, like not going to hard for the risk of breaking down muscles etc

    Thanks for a great article!

  • Hi, I started this fast almost exactly 24 hrs ago. I did everything to the T yesterday – had a cup of coffee, took a brisk 4 hour walk within 30 minutes of waking, drank water with himalayan salt throughout my walk, drank a couple bottles of water with Kegenix Prime and had two table spoons of Bulletproof brain Octane Oil in herbal tea post walk/before bed. My ketones levels are now at a mere 3.4. Why?! I generally eat a very healthy slow carb diet and I’m only 15 lbs over my goal weight. Can you help me make sense of this? In the mean time, I will go on another long walk hoping to achieve ketosis (5mmol+). Thanks!

  • Starting the Ferris style three day fast later today – in the poscast/book tools for titans he mentions putting lemon juice in the water. Is that needed and does it have any effects pr venting ketosis / autophagy?

  • Great article, have done several medium to long fasts and always wondered why I didn’t get into deep ketosis….. now I have an idea ! Thanks for posting.

  • One thing I have noticed with an extended fast is that it not only helps me physically reset but it helps me to mentally stay on track and not go askew.

  • Hi Tim,

    Been doing the Keto eating for about 3 weeks, decided to do a 3 day fast for the first time. Wondered if drinking coffee with one tablespoon MCT Oil + one tablespoon Butter, once a day is not breaking my fast??

    Appreciate the article.

    • Hi,

      Afraid I’m not Tim; this is just his method.

      But to answer your question…

      Technically yes, consuming any form of calories breaks a fast. By the strictest definition.

      However, assuming the aim isn’t the vanity of “I did a 3 day water fast”, and instead you’re optimizing towards a health goal, then it matters less.

      With the method above, TIm is aiming to transition as quickly as possible into ketosis. And he includes exogenous ketones as part of the “on ramp” into ketosis to reduce the sub-optimal feeling whilst one isn’t eating, and wants their ketone production to ramp up.

      The coffee + MCT + butter combo doesn’t contain any carbohydrates, so won’t slow down your transition into keto.

      (one thing to mention is that any milk you add does contain small amounts of carbohyrdate in the form of a sugar called lactose)

      So I’d say go for it. Once you hit keto, you’ll get the therapeutic benefits associated with it.

    • Some proponents of fasting such as Martin Berkham assert that as long as you stay under 50 calories, you are still in the fasted state.

      From the evolutionary point of view it would make sense. If you were wandering across a desert for days, without much to eat, you would still find the occasional bug (full of fat) or worm to put in your mouth. Since it would not give you nearly enough calories, you would stay in the fasted state.

      A teaspoon of butter contains 33 calories. Put one into your coffee and drink it slowly, taking an hr or so. This allows you for two cups, and you are still in the fasted state.

      I did this during my last 5 day fast: 1 coffee in the morning. My ketones were off the chart and reached 6mmol/L with blood sugar level in the 68 mg/L range or so.

      Hope this helps