Intermittent Fasting - Lose Fat, Live Longer

by GregHaglund 11754 views Nutrition

Intermittent Fasting - Lose Fat, Live Longer

Intermittent fasting (IF) is one of the world’s most popular health and fitness trends. People are using it to lose weight, improve health and simplify their lifestyle. Many studies are supporting positive benefits for brain and physique enhancement. It may even help you live longer1.

What is intermittent fasting?

Intermittent fasting is a term given to an eating plan that cycles between periods of fasting and eating. Sometimes planned and other times at random. Note: Planned is best!

Intermittent fasting is not a diet but more an eating pattern. It can be adapted to any diet or nutritional plan. There are many ways to do intermittent fasting and we will take a deeper dive into these approaches below. Some fasts can last only 16 hours and others as long as 14 days.

Humans have been fasting throughout evolution. Sometimes it was done because food was not available and other times as part of religious practice or culture. When you think about it, our hunter-gatherer ancestors didn’t have supermarkets, refrigerators or food available year-round. Sometimes we couldn’t find anything to eat, and our bodies evolved to be able to function without food for extended periods of time using ketones as energy broken down from body fat.

Based on our evolution, intermittent fasting should be considered the norm rather than the exception. It seems in our history it was more natural than eating 5 – 6 meals a day consistently. 

What are the benefits of Intermittent Fasting?

Fasting creates several benefits on a cellular and molecular level. In fact, fasting can change gene expression and profoundly improve the way you look, feel and perform. Here are a few areas where studies have shown benefits…

Weight Loss: Intermittent fasting is commonly used as a method for enhancing weight loss or stimulating weight loss that has stalled. It stands to reason that if you fast for a period you are going to eat fewer calories and potentially use more stored body fat (ketones) as fuel.

However, if you consistently underfeed your body with restricted calories in a non-fasting way, you may find fat loss stalls. Therefore, the practice of fasting 2-4 times per week is often more effective than 5-6 times per week.

Intermittent fasting also increases the release of Norepinephrine (Noradrenaline). This catecholamine promotes fat burning for energy. As a result, intermittent fasting may increase your metabolic rate by 3.6-14%2.

During this period of fasting, your body shifts into a temporary state of ketosis. This natural survival mechanism allows your body to perform at a high or higher level in the absence of carbohydrates or other calories by burning fat as fuel. This process can be further enhanced by consuming exogenous (external) ketones like BHB from KETO SWITCH™.

In a meta-analysis from 2014, it was shown that intermittent fasting may boost weight loss by 3-8% over 3-24 weeks3. In this review, they found that participants lost 4 – 7% of their belly fat. This is exciting because belly fat is not only where most people want to burn fat but is also the most metabolically damaging fat storage site.

Human Growth Hormone (HGH): Studies have documented a 500% increase in growth hormone with intermittent fasting4. This may assist with fat loss, muscle building and recovery.

Insulin: Insulin sensitivity is improved by 37% with the practice of intermittent fasting. This means you can utilise carbohydrates more efficiently and reduce carbs storing as fat. You will have more energy and less fatigue. Intermittent fasting can also reduce insulin resistance, lowering blood sugar by 3-6% and fasting insulin levels by 20-31%5.

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

Cellular repair: When fasted, your cells go into overdrive repair processes. One study showed that intermittent fasting causes less muscle loss and more muscle repair than standard continuous calorie restriction. Also, autophagy (the process where cells digest and remove old and dysfunctional proteins that build up inside them) is increased by 17 -21%6.

Inflammation: Studies have also shown reductions in inflammation, a key driver of many chronic diseases including diabetes and obesity7.

Brain Health: Intermittent fasting increases a hormone called BDNF (Brain Derived Neurotrophic Factor). This may help with the growth of new brain cells and nerves8. It may also enhance learning ability, reduce brain fog, improve focus, alertness and protect against Alzheimer’s, Parkinson’s and Dementia. This is an exciting field of research and one I have certainly felt the benefits of.

Anti-aging: Intermittent fasting can extend lifespan in rats. Studies showed that fasted rats live as much as 36-83% longer9. Human studies are still required. However, in blue zones (areas where the population regularly live to over 100 years of age) it is common for the populations to experience forms of intermittent fasting or calorie restriction.

But is it safe and are there any side effects?

Intermittent fasting has an outstanding safety profile. There is nothing dangerous about not eating for a short period of time providing you are healthy and stay well hydrated. We will provide you with a strategy below to get the most out of fasting with the least amount of side effects.

Side effects? What side effects?

Hunger is the main side effect of intermittent fasting. You may also feel weak and a little foggy in the brain.  This is only temporary as your brain and body may not be used to using ketones for energy. You can overcome many of these side effects by using KETO SWITCH™ to become keto adapted faster.

It’s also worth mentioning that some studies suggest women don’t do well on extended fasts. Therefore, it is my opinion that women should keep their fasting times to a maximum of 24 hours and no more often than three times a week. For women, I would personally recommend the 16/8 approach two to three times a week.

This means fasting for 16 hours and then consuming your food over the following 8 hours in the day.

There is a suggested evolutionary reason women don’t respond as well as men. Women were generally the caregivers. They stayed at camp and looked after the children and elderly. Camp was where the food was stored so women would have had access to more food than the men who may have been on hunts for extended periods of time without food.

Methods... Putting theory into practice.

The 5:2 Diet: On two non-consecutive days of the week, only eat 500 calories. Eat normally the other 5 days. This approach is like Eat – Stop – Eat except there is an allowance for 500 calories. Generally, we encourage these calories to come from vegetables, fruits and fats. Make sure the low calorie days are low exercise days.

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. This should only be attempted on non-training days and no more than twice a week.

The 16/8 Method (LeanGains): This method involves skipping breakfast and lunch and restricting your daily eating period to 8 hours. For example, stop eating at 8 pm Monday and start eating again at 12 pm on Tuesday. Or stop eating at 7 pm Tuesday and start eating again at 11 am on Wednesday.

These methods should all help you lose weight, providing you don’t compensate by eating considerably more during the eating periods or extend the periods of fasting for too long (more than 3 days), where your metabolism may slow down and hold onto body fat.

I’ve personally found the 16/8 method to be the simplest, most sustainable and easiest to stick to. This is the method we will discuss in more detail below and provide you with a strategy to maximise results and minimise side effects.

Steps to conducting the perfect 16/8 fast...

Step 1:

Eat your last meal at 7 or 8 pm – Make sure this meal is relatively low in carbohydrates. The goal here is to fill up on lots of fibrous vegetables, protein and fats. This will help keep your blood sugars low and boost you into ketosis quicker. Make sure you are consuming adequate salt (Pink or Sea) in this meal as it may help improve sleep and maintain proper thyroid function.

Step 2:

Upon Rising consume my Fat Burning Stack – 1 serving of KETO SWITCH™, THERMAL SWITCH™, L-Carnitine and AMINO SWITCH™. This super stack will maximise your fat burning and minimise your muscle loss.

It will also help you keto-adapt.

KETO SWITCH™ – Supplies exogenous (external) ketones to help switch your body into ketosis, turn on brain function and control hunger. Ketosis is a natural state of fat burning.

THERMAL SWITCH™ – Contains caffeine and other stimulants which may boost your metabolic rate, support fat burning, increase energy, control your appetite and provide focus.

L-Carnitine – Helps to transport fatty acids across the mitochondrial membrane to be used as energy. L-Carnitine also improves hormone sensitivity which may help enhance the benefits of increased growth hormone.

AMINO SWITCH™ – Provides the perfect human ratio of essential amino acids found in a complete protein but with higher bioavailability and lower calories. AMINO SWITCH™ allows you to continue burning fat without burning muscle. 

Step 3:

Cardio – Head out and do your cardio. You can do HIIT (High-Intensity Interval Training) or LISS (Low-Intensity Steady State). Studies suggest HIIT may be more effective for fat loss and muscle preservation.

Step 4:

Consume AMINO SWITCH™ – When you return from your exercise it is recommended that you consume another serve of EAA’s to assist with recovery and reduce muscle breakdown.

Step 5:

Break the fast – Normally this would be breakfast. However, it will be at either 11 am or 12 pm depending upon the time of your last meal the night before. This meal may contain a balance of Protein, Carbohydrates and Fats.


Can I drink liquids during the fast?

Yes. Water, coffee, tea and the above-mentioned supplements. Do not add sugar to your tea or coffee. However, you can add butter or MCT oil (Medium Chain Triglycerides) to your tea or coffee. Keep in mind if you are using THERMAL SWITCH™ it contains caffeine and shouldn’t be consumed around the same time as coffee. Also, don’t consume stimulants late in the afternoon or evening.

Isn’t skipping breakfast unhealthy?

No, it’s not. Providing you make sure you eat healthy food for the rest of the day. Also, you are only fasting (missing breakfast) two to three times a week10.

Will fasting slow my metabolism?

No. Most studies show that short-term fasts boost your metabolism. However, longer fasts (3 days or more) may suppress your metabolism.

Can I use supplements while fasting?

Yes. I have provided you with a Fat Burning Stack above and you may also wish to add in a small serve of MCT oil, especially if you are fasting for 24 hours or doing a 5:2 fast. Also, keep in mind that some supplements are fat soluble so may need to be consumed with fats like MCT or Coconut oil.

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Can I work out while fasted?

Yes, fasted workouts are fine. I suggest in the beginning you fast on days where you are doing cardio only.

However, as you become more advanced and your body adapts you may wish to implement the 16/8 approach for longer periods at a time which may mean you are fasting on weight training days.

When this is the case I would strongly suggest you use Revive™ (BCAA’s) during your workout to prevent muscle damage and promote greater fat loss.

Will fasting cause muscle loss?

All forms of calorie restriction can cause muscle loss. However, using AMINO SWITCH™ before and after exercise and Revive™ during exercise should significantly reduce muscle loss and may even increase muscle gain. One study shows that intermittent fasting causes less muscle loss than regular calorie restriction11.


Intermittent fasting has many profound benefits for health and wellbeing. It may also support fat loss and muscle recovery if done correctly with the right supplement protocol. However, fasting is not for everyone. Please make sure if you wish to attempt fasting you start with the 16/8 method and follow my steps outlined above. This strategy is likely to provide you with the greatest benefits and the least number of struggles.

In time, you may even come to enjoy fasting like I have as it gives your digestive system a rest and simplifies life with a smaller period of eating. I have even found anecdotally that my digestive system has improved as a result of combining intermittent fasts with regular consumption of bone broth (I will tell you all about this amazing super food in another blog).

Try a fast on for size and see if it fits.

You may not enjoy it your first time. It took me several (5-6) attempts to find my groove and perfect the protocol above. Hopefully, with my wisdom and previous experience, you will find your groove quickly and reap the many rewards of intermittent fasting. 


The above article is merely a guide and is in no way a recommendation or a treatment protocol for any health conditions or diseases. You should always consult with a qualified health care provider before changing your supplement, training or nutritional strategy. Intermittent fasting should not be attempted by pregnant or breastfeeding women, anyone consuming prescription medication or children under the age of 15 unless advised by a qualified health care provider. If you have a history of an eating disorder then you should consider carefully if Intermittent Fasting is the right protocol for you. 

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Valter D. Longo et al, Fasting: Molecular Mechanisms and Clinical Applications Cell Metab. 2014 Feb 4; 19(2): 181–192. Mansell PI, et al Enhanced thermogenic response to epinephrine after 48-h starvation in humans. Am J Physiol. 1990 Jan;258(1 Pt 2):R87-93.

Adrienne R. Barnosky, et al Intermittent fasting vs daily calorie restriction for type 2 diabetes prevention: a review of human findings DOI:

K Y Ho et al Fasting enhances growth hormone secretion and amplifies the complex rhythms of growth hormone secretion in man J Clin Invest. 1988 Apr; 81(4): 968–975.

Heilbronn LK et al Alternate-day fasting in non-obese subjects: effects on body weight, body composition, and energy metabolism. Am J Clin Nutr. 2005 Jan;81(1):69-73.

Kim I et al Mitochondrial degradation by autophagy (mitophagy) in GFP-LC3 transgenic hepatocytes during nutrient deprivation. Am J Physiol Cell Physiol. 2011 Feb;300(2):C308-17. doi: 10.1152/ajpcell.00056.2010. Epub 2010 Nov 24.

Johnson JB et al Alternate day calorie restriction improves clinical findings and reduces markers of oxidative stress and inflammation in overweight adults with moderate asthma. Free Radic Biol Med. 2007 Mar 1;42(5):665-74. Epub 2006 Dec 14. Lee J et al Dietary restriction increases the number of newly generated neural cells, and induces BDNF expression, in the dentate gyrus of rats. J Mol Neurosci. 2000 Oct;15(2):99-108.

Goodrick C.L et al Effects of Intermittent Feeding Upon Growth and Life Span in Rats. Gerontology 1982;28:233–241 Jessica L. Bachman et al Exercising in the Fasted State Reduced 24-Hour Energy Intake in Active Male Adults. Journal of Nutrition and Metabolism Volume 2016 (2016), Article ID 1984198

Varady KA et al, Intermittent versus daily calorie restriction: which diet regimen is more effective for weight loss? Obes Rev. 2011 Jul;12(7):e593-601



Owner - Switch Nutrition

I have been formulating sports nutrition products for more than 20 years. Supplements, Training, Nutrition and Health have become my passion and my profession. Switch Nutrition manufacture 100% natural cutting edge products to help people get the best results for their health and performance.

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