The Quick Guide To Fasting Lingo

The “Poor Cousin’s Guide” to fasting terms and benefits.

Article by Anita Aldridge | 10 Jan, 2021

(Editor's note: Including fatty coffee or tea is one way that's frequently recommended by some experts to help those unused to longer-term fasting adjust. This technically breaks a strict fast, but can aid in getting used to going longer periods without solid foods. It should also be noted that there is controversy in the community as to whether consuming broth during a fast can raise blood sugar or stimulate insulin. You do you, so experiment, watch and listen to your body's signals, and include broth if you do not notice any adverse effects.)

You may have come across some funny looking numbers related to fasting here in Keto-Land.

16/8, 18/6, 20/4

These are several types of fasts which stand alongside the ketogenic lifestyle, some of which you are probably doing already without even knowing it. Go you!!

Fasting has a variety of benefits, including weight loss, internal healing, autophagy (process of cell renewal- applied in this case to protein), energy production and mental clarity. We naturally fast every night without thinking about it. The time between whenever we stop eating in the evening, to the first time we have a meal the next day, is time we're fasting (which is why your first meal every day is called break-fast).

Did you realise, during the day if you’re only eating when you are hungry, you’re probably already doing some additional fasting? Having a bulletproof coffee or tea in the morning and then not eating a meal until midday or in the evening is actually an extended fat fast.

To summarize some fasting lingo, let's discuss those weird numbers we mentioned earlier.

The 16/8

If we sleep eight hours overnight, then we’re likely not eating for a minimum of twelve hours (which assured you've stopped eating a good four hours prior to bed). That’s a 12-hour fast, and it's usually the easiest and most natural with which to start. Hopefully, the time between eating dinner and going to bed is actually a lot longer than that, and thus most people find that they can very easily extend their overnight fasting into what’s called a 16/8. This is 16-hours overnight not eating and only eating during 8-hours of the day. Does that make sense?

Let’s look at the other kinds of fasting that you might like to look at incorporating in your ketogenic lifestyle.

The 18/6

No prizes for guessing that this means. We fast for 18-hours and eat during a 6-hour window! Once you know what the two numbers and their order mean, it gets easier to understand from here.

The fun thing about the 18/6 is once we hit 18 hours fasting, our bodies begin to do something we mentioned earlier, called autophagy. Autophagy is the automatic process of concentrating on renewing the body's cellular structure. Because our body is smart, it looks for cells that it doesn’t need anymore and purges or fixes them. This happens most frequently when we are fasting.

This is particularly good news for those of us who have lots of body fat percentage to lose and have been dreading the post loss saggy skin. Fasting experts, like Dr. Jason Fung, frequently reports that his clients see very little loose, saggy skin after incorporating his fasting regimen into their lifestyle, thus fasting can be a tool to help reduce these issues while we are losing weight. The more time we can spend in a fasted state, the better chance we have of our body dealing with that skin for us without having to fork out for cosmetic surgery somewhere down the road. It isn't a miracle-quick-fix-cure, but as with anything keto, trust the process and give your body all the tools it needs.

The 20/4

  • 20 hours fasting, 4 hour window to eat in: Check
  • Autophagy: Check

During the 20/4 window is when most people start to notice the real energy boost from fasting begin to kick in. Eating a good meal once a day and spending the rest of the time fasted, gives our bodies the best positive opportunity to turn any stored fat we have into fuel. While it's important to avoid eating too little, be aware that you don't necessarily need to eat all your macros in that one meal, either. Eat very well until you’re satisfied, and use Dr. Fung’s tips of water, coffee, tea, bone broth, the occasional fattened-up version of those, and electrolytes to keep you going until you break your fast. It's also a good idea to eat very well for a day or two between longer fasting times and before starting the extended fast again.

The 24

  • No solid food for one whole day: Check
  • Autophagy: Check

Drink only allowable liquids: Water, Coffee, Tea, Bone Broth, make them bulletproof when necessary, and add electrolytes.

The 72 (3 days)

The 72-hour fast is the fast for you if you are finding that you have stalled for longer than 3 months. Completely stalled (no movement in clothes, measurements, photos or scale) and none of the other fasting techniques practiced regularly (several times a week) are working for you.

Benefits of this kind of extended fasting are concentrated healing, organ healing, PCOS, Type 2 diabetes and stubborn fat loss. The reason an extended fast like this is sometimes necessary is because it helps clear the liver. Our livers store glycogen, and if we have any glycogen stored in our liver from excess carbohydrate or protein consumption, it needs to be completely used by our body first before the liver will begin to access our stored fat again.

(Note: If you have any severe medical conditions or are on any kind of prescription medication, be sure to check with your medical practitioner about the advisability of fasting. Some medicines may need to be adjusted so they don’t cause unhealthy side effects, which should only be done under appropriate medical supervision.)

A three day fast can feel like going back to the beginning of our ketogenic journey. We’ve been told for so long that we must eat, even if we have been getting used to only eating when we are hungry, that it can feel unnatural to not eat once we start feeling those signs. Our bodies may put out hunger signals, but in the case of the 72-hour fast, if we really need to break a stall, this is a matter of choosing to ignore them for a time.

After a 72-hour fast the scale may go down and back up once we resume eating normally. This is normal. The stall symptoms, however, will be broken as long as you don’t go back to consuming excess carbohydrates and protein.  

Anything Else?

There are plenty of longer fasts and other ways of doing fasting, but this is enough for the Poor Cousin's Guide. The easiest way to do any kind of fast is to gently begin push your own boundaries. Tomorrow, you might go one more hour before you eat. The next day, add an extra hour. It’s a matter of testing to see how much we are being driven by the clock or whether our body really needs fuel.

With any kind of fast, it’s important to keep our fluid and salt intake the same as usual. Dr Fung recommends water, black tea, black coffee and bone broth. He also talks about drinking fatty coffee or adding fat to bone broth when our brain is saying we are hungry, but the rest of us isn’t really sure. If you live a spiritual lifestyle, you may also like to connect your nutritional fasting with prayer.

Before we finish, there are some people who should definitely not fast. If you are breast feeding, pregnant, severely underweight, or under 18 years old, then you should not fast until it is safe for you to do so.

Dr. Jason Fung and Jimmy Moore have published an amazing resource on fasting, it has science- which is great science, it’s comprehensive without being heavy, and they explain the technical bits, so everyone will enjoy it. The Complete Guide To Fasting delivers exactly what it promises. Read it. You’ll love it.

Keto Strong.

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