Home  /  All  /  Lifestyle

Your Guide to Intermittent Fasting

Written by
  Published on March 21st, 2019
  Reading time: 3 minutes
  Last modified January 7th, 2023

What is Intermittent Fasting?

Intermittent fasting (IF) is an eating protocol where you sustain a period without food. Most people already practice intermittent fasting by abstaining from food overnight during sleep, and then returning to a period of consumption from morning to evening.

Through understanding intermittent fasting in this respect, you might begin to recognize fasting more as a regular part of life, as opposed to a concerning method of starvation. In fact, it is the source of the word “breakfast”–the first meal in which the overnight fast is broken. Intermittent fasting is simply a protocol that utilizes fasting and feeding windows to achieve different health-related outcomes.

Are There Health Benefits to Intermittent Fasting?

Fat Loss

Fasting is clearly a tool that can be used for losing weight, particularly fat mass. When the time frame for your feeding window is reduced, you can be more in control of when you eat. Ideally, you’ll target this window for time at home where you can cook instead of being at the mercy of eating out on the road which can lead to limited nutritional options.

If you are aiming for caloric restriction, shortening the eating window will further support this process. By reducing the spikes in blood sugar, you will have more stable blood glucose levels during intermittent fasting, ironically making it easier to go without food the deeper into a fast you are. Aside from weight loss, a study comparing lean body mass retention on a calorie-restricted diet to an alternate-day fast (ADF) and found favorable results for the ADF group. [1]

Cognitive Clarity

Fasting has been seen to be powerful when impacting our cognitive clarity. It makes sense–if we are without food, a bit of clarity wouldn’t go amiss when trying to find some. Evolutionarily, this could mean we would have had a hard time surviving if starvation in between long periods of eating led to immense brain fog, negatively impacting our ability to locate our next meal.

An Increase in Human Growth Hormone

Fasting has been shown to increase secretion of human growth hormone. [2] During fasting, there is a spike in early-morning growth hormone secretion. This secretion then remains uninterrupted by blood glucose rises and insulin secretion throughout the fasting period.

Other benefits include:

  • Performance enhancement
  • Increased energy
  • Reduction of inflammation

Fasting has associated benefits in:

  • Alzheimer’s disease and other neurodegenerative diseases
  • Cancer
  • Diabetes
  • Cholesterol management

Types of Intermittent Fasting

Intermittent fasting can be broken down into two sub-sections: short- and long-term fasting.

Short-Duration Fasting


This protocol is simply a 16-hour fasting window followed by an 8-hour eating window. This routine can be followed daily or every other day. For example, we finish our final meal at 8pm (dinner) and we fast until 12pm the following day (lunch). This gives us an eating window of 8 hours (12–8pm). This can be brilliant if you live a busy lifestyle whereby you are pressed for time during mornings or you are out of the house commuting where healthy options for food are few.


Also known as warrior fasting, this is a fast ratio typically adopted by warriors. Typically, a warrior will be marching, fighting, and sleeping for 20 hours per day, leaving them with only a 4-hour eating window. This style of fasting can be difficult because your calorie requirement still needs to be sufficiently high, but you have four hours to consume adequate amounts of food and nutrition. This can be difficult when satiety prevents you from eating enough.

Long-Duration Fasting

24 hours

Fasting for 24 hours is where you eat one meal a day at roughly the same time. This interval could be used for alternate day fasting (ADF), where you have a normal eating window for one day, abstaining from food the next day, and then returning to normal eating on the day after that.

36 Hours 

A 36-hour fast is where you sustain a longer period of fasting between meals. This could be where you have breakfast and then you would not eat until the following day towards late evening.

Note: You should always consult your health practitioner before trying any of these methods.

Intermittent Fasting and Ketosis

Is it a match made in heaven? It might just be. IF and a ketogenic diet can go hand in hand. Being in a state of ketosis before beginning a fast can help ease the hunger pangs seen at the start of a fast that are often attributed to the oscillating blood glucose levels of a diet high in carbohydrates. Fasting will regulate your body’s blood glucose levels and, in-turn, your blood ketone levels, making the process of keto-adaptation occur a little more smoothly.

At ketogenic.com, we are committed to supporting, inspiring, and educating people on the benefits of living a ketogenic lifestyle. We do this by bringing together the top researchers, practitioners, and thought-leaders who provide resources, experience, and awareness associated around the Ketogenic diet. Utilizing the latest cutting-edge research along with practical experience, the team at ketogenic.com aims to foster awareness, understanding, and connectedness in helping others optimize their life on a ketogenic diet.



Catenacci, V. A., Pan, Z., Ostendorf, D., Brannon, S., Gozansky, W. S., Mattson, M. P., … & Troy Donahoo, W. (2016). A randomized pilot study comparing zero‐calorie alternate‐day fasting to daily caloric restriction in adults with obesity. Obesity, 24(9), 1874-1883.


Ho, K. Y., Veldhuis, J. D., Johnson, M. L., Furlanetto, R., Evans, W. S., Alberti, K. G., & Thorner, M. O. (1988). Fasting enhances growth hormone secretion and amplifies the complex rhythms of growth hormone secretion in man. The Journal of clinical investigation, 81(4), 968-975.

Leave a Comment

Your email address will not be published. Required fields are marked *

As a Member, you get instant access to personalized meal plans, exclusive videos & articles, discounts, a 1 on 1 Coaching Session, and so much more. As a member, you join our mission of empowering 1,000,000 people to positively change their lives throughout the world. Get started today.


A Great Deal
$ 19
99 /month
  • 7-Day Free Trial
  • Cancel Anytime


3 Months Free
$ 179
  • 3 Months Free
  • Cancel Anytime


Membership for Life
$ 349
  • Lifetime Access
  • Limited Availability