Intermittent Fasting

Intermittent fasting (IF) is currently a very popular diet ‘trend’.

Definition: Intermittent fasting (IF) is an eating DIET pattern that cycles between periods of fasting and eating.

People are using it as a fat and weight loss DIET technique and to simplify their eating habits.

There have been proven studies that highlight the positive effects that it has on the body at both an extracellular and intracellular level. (1)

The diet type doesn’t at all discriminate against food ‘type’ but rather when you eat.

Therefore, it is actually more of an eating pattern as opposed to a diet type in my opinion.

Fasting has been a common thing for hunter-gatherers in the past. They never had supermarkets, refrigerators or adequate cooking material and consequently, humans have evolved to be able to function without food for extended periods of time.

During the fasting periods, you eat either very little or nothing at all.

Difference between time-restricted eating & IF


People are getting confused between time-restricted eating and IF. Time-restricted eating is actually a form of intermittent fasting highlighted by the 16:8 method below however there are many other time-restricted eating methods that fit under this umbrella.

These are the most popular methods:

The 16/8 method: It involves skipping breakfast and restricting your daily eating period to 8 hours, such as 1–9 p.m. Then you fast for 16 hours in between.

Eat-Stop-Eat: This involves fasting for 24 hours, once or twice a week, for example by not eating from dinner one day until dinner the next day.

The 5:2 diet: With this methods, you consume only 500–600 calories on two non-consecutive days of the week, but eat normally to your baseline the other 5 days.

By reducing your calorie intake, all of these methods should cause weight loss as long as you don’t compensate by eating much more during the eating periods.

In my opinion, the 16/8 method is a much healthier and more convenient method opposed to the heavily restrictive nature of the other two.

How It Affects Your Cells and Hormone
It isn’t just the external body composition that is affected when fasting. The body on an intracellular level undergoes significant changes. I believe it is important to know what is actually going to happen to your body before undertaking any restrictive diet practices.

Here are some changes that occur in your body when you fast:

Human Growth Hormone (HGH): The levels of growth hormone skyrocket, increasing as much as 5-fold. This has benefits for fat loss and muscle gain, to name a few (3,4)

Insulin: Insulin sensitivity improves and levels of insulin drop dramatically. Lower insulin levels make stored body fat more accessible (2).

Cellular repair: When fasted, your cells initiate cellular repair processes. This includes autophagy, where cells digest and remove old and dysfunctional proteins that build up inside cells (4)

Gene expression: There are changes in the function of genes related to longevity and protection against disease (5)

These changes in hormone levels, cell function, and gene expression are responsible for the health benefits of intermittent fasting. Because of these changes in hormones (including the increase in fat burning hormone norepinephrine (noradrenaline), short-term fasting may increase your metabolic rate by 3.6–14% (5)

Overall Positives of IF

> Intermittent Fasting Can Help You Lose Weight and Belly Fat
> Intermittent Fasting Can Reduce Insulin Resistance, Lowering Your Risk of Type 2 Diabetes
> Intermittent Fasting Changes The Function of Cells, Genes and Hormones
> Intermittent Fasting is very efficient for time-poor people who don’t enjoy meal preparation nor calorie counting.

Overall Negatives

 of IF
> Becoming highly obsessed with following the intermittent fasting pattern precisely
> Appetite not being effectively satisfied.
> Can alter the balance of your food control and stress hormones (leptin, ghrelin and cortisol)

Who Should Be Careful Or Avoid It?
Intermittent fasting is certainly not for everyone. It takes a significant amount of discipline and restriction.

If you are someone who is underweight, has had a history of eating disorders or someone that like stop count calories then you should definitely avoid it. 

Although some studies have highlighted the positive affects of muscle gain, I believe it is much easier to gain muscle mass and weight by not fasting.

Kids should definitely not fast and the benefits have been shown to be less successful in women than men.

I hope that this helps you in choosing your diet type of choice.

Other diet types to consider for fat loss would be: very low and low carb dieting, ketogenic diet, isocaloric diet and then looking at how it is best to periodize your calories, deficit amounts and diet breaks over a lengthy and sustainable period of time.

Daniel Maitland – TWM Owner, S & C Coach

1. In-Depth Review: Excess Adiposity and Disease
Review Article. Intermittent fasting vs daily calorie restriction for type 2 diabetes prevention: a review of human findings
Adrienne R.Barnoskya, Kristin K.Hoddy, Terry G.Untermana, Krista, A.Varady

2. Am J Clin Nutr. 2005 Jan;81(1):69-73.
Alternate-day fasting in nonobese subjects: effects on body weight, body composition, and energy metabolism.
Heilbronn LK1, Smith SR, Martin CK, Anton SD, Ravussin E.

3.. J Clin Invest. 1988 Apr; 81(4): 968–975.
PMCID: PMC329619
PMID: 3127426
Fasting enhances growth hormone secretion and amplifies the complex rhythms of growth hormone secretion in man.
K Y Ho, J D Veldhuis, M L Johnson, R Furlanetto, W S Evans, K G Alberti, and M O Thorner

4 . Autophagy. 2010 Aug 16; 6(6): 702–710.
Published online 2010 Aug 14
PMCID: PMC3106288
PMID: 20534972
Short-term fasting induces profound neuronal autophagy
Mehrdad Alirezaei,#1 Christopher C. Kemball,#1 Claudia T. Flynn,1 Malcolm R. Wood,2 J. Lindsay Whitton,corresponding author1 and William B. Kiosses2

5. . Am J Physiol. 1990 Jan;258(1 Pt 2):R87-93.
Enhanced thermogenic response to epinephrine after 48-h starvation in humans.
Mansell PI1, Fellows IW, Macdonald IA.