*Our Thanks go to Switch Nutrition for this Article! - Protein King*
Intermittent feasting is a term we have coined at Switch HQ to describe an eating plan that cycles between extended periods of fasting (not eating) and short periods of feasting (eating). Sometimes planned and other times at random. Note: Planned is best!
Intermittent feasting is not a diet but more of an eating pattern. It can be adapted to any diet or nutritional plan. There are many ways to adapt intermittent feasting and we will take a deeper dive into these approaches below.
Humans have been feasting and fasting throughout evolution. Sometimes we fasted because food was not easily available and other times as part of religious practice or culture. Then we would feast as part of celebration or to break a fast. When you think about it, our hunter-gatherer ancestors didn’t have supermarkets, refrigerators or food available year-round. Sometimes they wouldn’t be able to find anything to eat, and as a result our bodies have evolved to function without food for extended periods of time using ketones as energy broken down from body fat.
Based on our evolution, intermittent feasting 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 over the wider part of the day.
Fasting and feasting create several benefits at a cellular and molecular level. In fact, it can change gene expression and profoundly improve the way you look, feel and perform. Many studies are supporting positive benefits for brain and physique enhancement. It may even help you live longer. Here are a few areas where studies have shown benefits…
WEIGHT LOSS: Intermittent feasting 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 an extended period you are going to eat fewer calories when you finally feast. This often leads to the use of 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 and feasting 3-4 times per week can be more effective than 5-6 times per week especially for women. Fasting followed by feasting also increases the release of Norepinephrine (Noradrenaline). This catecholamine promotes fat burning for energy. As a result, IF may increase your metabolic rate by 3.6-14%. During the fasting period your body shifts into a temporary state of ketosis. This natural survival mechanism allows your body to perform competently 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 IF may boost weight loss by 3-8% over 3-24 weeks. 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.
HUMAN GROWTH HORMONE (HGH): Studies have documented a 500% increase in growth hormone with IF. This increase may assist with fat loss, muscle building and recovery.
INSULIN: Insulin sensitivity is improved by 37% with the practice of IF. This means you can utilise carbohydrates more efficiently and reduce carbs storing as fat. You may experience more energy and less fatigue. IF can also reduce insulin resistance, lowering blood sugar by 3-6% and fasting insulin levels by 20-31%.
GENE EXPRESSION: There are positive 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 IF caused 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%.
INFLAMMATION: IF studies have also shown reductions in inflammation, a key driver of many chronic diseases including diabetes and obesity.
BRAIN HEALTH: IF increases a hormone called BDNF (Brain Derived Neurotrophic Factor). This may help with the growth of new brain cells and nerves. It may also enhance learning ability, reduce brain fog, improve focus, alertness and protect against Alzheimer’s, Parkinson’s and Dementia.
ANTI-AGING: IF can extend lifespan in rats. Studies showed that fasted rats live as much as 36-83% longer. 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 communities to practice forms of IF or calorie restriction.
IF has an outstanding safety profile. Provided you are healthy and stay well hydrated, there is nothing dangerous about not eating for short periods of time. We will provide you with a strategy below to get the most out of fasting and feasting.
Hunger is the main side effect of IF during the fasting period. 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 most of these issues by using KETO SWITCH™ to become keto adapted faster.
It’s also worth mentioning that some studies suggest women don’t do as well on extended fasts.
For women, we would recommend the 16/8 approach two to three times a week (this means fasting for 16 hours and then feasting for 8 hours in the day). There is a suggested evolutionary reason women don’t respond as well as men to IF. Women were generally the caregivers. They stayed at camp/home 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.
This method involves skipping breakfast and your mid-morning snack and restricting your daily eating period to 8 hours. For example, stop eating at 8pm Monday and start eating again at 12pm on Tuesday. Or stop eating at 7pm Tuesday and start eating again at 11am on Wednesday.
This method should help you lose weight, providing you don’t compensate by feasting on considerably more during the 8-hour window or extend the periods of fasting for too long.
We have found the 16/8 method to be the simplest, most sustainable and easiest to stick to while getting some outstanding results. This is the method we will discuss in more detail below and provide you with a strategy to maximise results.
Eat your last meal at 7 or 8pm. Your daily training time will dictate the serving size of this meal. The goal here is to fill up on lots of fibrous vegetables, protein and a moderate amount of carbohydrates or fats. This will help keep your blood sugar levels
stable and allow your body to reach a state of ketosis faster. Make sure you are consuming adequate salt (pink or sea salt) in this meal as it may help improve sleep and maintain proper thyroid function.
Upon rising consume the Ultimate Fat Burning Stack –
• ½ - 1 serve of KETO SWITCH™
• ½ - 1 serve of THERMAL SWITCH™
• ½ - 1 serve of AMINO SWITCH™
This super stack will maximise your fat burning and minimise your muscle loss. It will also help you keto-adapt quicker.
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.
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.
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.
Consume AMINO SWITCH™ – When you return from your exercise we recommend this extra serve of EAA’s to assist with recovery and reduce muscle breakdown.
Break the fast – Normally this would be breakfast. However, it will be at either 11am or 12pm depending upon the time of your last meal the night before. This meal may contain a balance of Protein, Carbohydrates and Fats. With the calories
(not the grams) split between Protein (30%), Carbohydrates (30%) and Fats (40%).
Note: The below feasting windows can be changed. It does not matter when you start the 8-hour feasting window, do what works for you.
CAN I DRINK LIQUIDS DURING IF?
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 if you are sensitive to them.
DO I HAVE TO EAT A SET NUMBER OF MEALS PER DAY?
No. There is no set structure for the meal frequency (above is just a guide) on intermittent feasting days. We find that 3 meals work best in the allocated feasting window. Try to keep the feasting window the same each day, as your body will usually get hungry when you are used to eating. It’s also beneficial for creating a routine and compliance.
ISN’T SKIPPING BREAKFAST UNHEALTHY?
No, it’s not. Providing you make sure to eat healthy food for the rest of the day. Also, you are only fasting (missing 1 to 2 meals) two or three times a week.
WILL IF SLOW MY METABOLISM?
No. Most studies show that short-term fasts actually boost your metabolism. However, longer fasts (2-3 days or more) may suppress your metabolism.
CAN I WORKOUT WHILE DOING IF?
Yes, fasted workouts are fine. In the beginning we suggest you fast on days where you are doing cardio only and not intense workouts. As you become more advanced and your body adapts you may wish to implement the 16/8 approach more often which may mean you are fasting on intense weight training days. When this is the case we would strongly suggest (as above) that you use AMINO SWITCH™ during your workout to prevent muscle damage and promote greater fat loss.
WILL IF CAUSE MUSCLE LOSS?
All forms of calorie restriction can cause muscle loss. However, using AMINO SWITCH™ before, during and after exercise should significantly reduce muscle loss and may even increase lean muscle gain.
IF 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, IF is not for everyone. Please make sure if you wish to attempt IF you start with the 16/8 method and follow the steps outlined above. This strategy is likely to provide you with the greatest benefits. In time, you may even come to enjoy IF like we have as it gives your digestive system a rest and simplifies life with a smaller period of feasting. We have even found anecdotally that many people suggest their digestive systems have improved because of IF.
Macronutrients and overall calorie intake should be cycled if fat loss is the primary goal. Generally, carbohydrates and total calorie intake is highest on training days. On non-training days carbohydrates are lower and fat is higher. Aim to keep protein high on all days (30–40% of overall calories).
You may not enjoy IF your first time. It took us all several (4-5) attempts to find our groove and perfect the protocol above. Hopefully, with our wisdom and previous experience, you will reap the many rewards of IF.
Disclaimer: This article is merely a guide and is in no way intended as 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. Supplementation should not be attempted by pregnant or breastfeeding women, anyone on prescription medication or children under the age of 15 unless advised by your qualified health care provider.
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