What you need to know about intermittent fasting?


Fad diets come and go. In our time on this planet we’ve already lived through high fat, low-fat, non-fat, high carb, low carb, South Beach, Atkins, Vegan, Keto, Paleo, The Zone, The Dukan, and let’s not forget the Cabbage Soup diet. Fasting however, has been around throughout time. Humans have been fasting for centuries - sometimes out of necessity when food was scarce, but also by choice for religious or cultural reasons. Is there a physiological benefit to fasting? Research is beginning to explore how periods of fasting can affect the body. We’ve talked about intermittent fasting HERE, but it’s been a while so let’s take another look.


Intermittent fasting is the practice of cycling between periods of eating and fasting. It is not a diet, where one is restricting calories or cutting out specific foods. Instead, it focuses on when you eat.


  • Studies have shown that fasting for at least 12 hours can improve fat oxidation (or fat burning).

  • Fasting for short periods of time has shown to lead to increased metabolic rate, increased energy and cognitive function.

  • Fasting helps lower blood sugar levels and normalize appetite through hormone regulation.

  • Intermittent fasting stimulates testosterone production.

  • Fasting allows your digestive system to take a breather and improves gut health.

  • Fasting has been shown to improve blood lipid profiles,

  • Periods of fasting stimulate the process of autophagy - cellular clean up - which is associated with longevity.


Depending on your goals, body type and level of comfort with fasting, there are different ways to approach this.

  1. Time Restricted Eating. This is simply not eating for a given number of hours - between 10 and 16 hours. The easiest way to do this is overnight. For example, if you finish dinner at 8pm, you would restrict your consumption of anything but water until 8am the following morning for a 12 hour fast, or as late as 12pm for a 16 hour fast. At 16 hours, this is commonly referred to as the 16:8 or LeanGains Method. Basically you would be skipping breakfast.

    Side note: Experts in the field don’t agree on what exactly breaks a fast. Most agree water is fine, but black coffee or tea and even small amounts of food are in the gray area. The research around fasting is still in its infancy. We personally tend to stick with water on 12 hour fasts and add black coffee to longer ones. Black coffee and tea can help suppress hunger, facilitate fat oxidation and boost autophagy.

  2. Eat-Stop-Eat. This method is geared towards weight loss. With this type of fasting, you would choose 1 - 2 days a week in which you would not eat for 24 hours. For example, if you finished your last meal on Saturday at 8pm you wouldn’t eat again until Sunday at 8pm.

  3. Alternate Day Fasting. Similar to Eat-Stop-Eat, this type of fasting involves eating every other day. You would consume zero calories on fasting days and eat freely on eating days.



Fasting is a stressor. While in general the body needs stressors in order to heal, regenerate and grow stronger, over stressing can be harmful. Some negative side effects can include irregular menstrual cycles, infertility, lack of libido, thyroid dysregulation, decreased performance, decelerated recovery, sleep issues, binge eating, holding on to extra weight, hair thinning or loss, and mood swings. Factors that may over stress the body and wouldn't fair well with fasting are:

  • Not consuming an adequate amount of calories from nutrient dense, nourishing, hormone supporting foods during the eating window.

  • Over doing anaerobic/glycolytically intense exercise while fasting.

  • Not getting enough good quality sleep

  • Leading a stressful lifestyle.

Women in particular need to be extra careful when it comes to fasting. The female hormone profile is very different from their male counterparts. Women who are very lean and or extremely active, have a history of hormone and/or thyroid dysregulation, are trying to conceive, pregnant or breastfeeding may want to stay away from fasting. Even women who are healthy tend to feel better and experience the best results from shorter and/or less frequent fasts.

Overall, fasting can have a profound effect on the body. It is easy, simple and free - but it is not for everyone. Pay close attention to your body, your performance, and how you are feeling. If you think you may have a condition which may contraindicate your reasons for fasting, consult your physician.

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