Pete Gawtry Fitness · Nutrition · 2020

The PG Fitness Guide to Intermittent Fasting

Everything you need to start fasting safely — the science, the protocols and the results to expect.

Intermittent Fasting

As different fads continue to influence people on their weight loss journeys, one interesting trend has taken this area by storm. We are talking about intermittent fasting, which is a process wherein individuals alternate between periods of fasting and eating. It was the most searched weight loss-related term in 2019 and a review article in The New England Journal of Medicine discussed it elaborately. If intermittent fasting is undertaken appropriately, it can serve several purposes. As stated already, it is a great tool to lose weight. Apart from that, it can assist in the reversal of type 2 diabetes, cut down costs, and save adequate time. This guide aims to acquaint you with various concepts and rules related to intermittent fasting, so you are equipped with complete information about the trend before you embark on this journey. Note: Although intermittent fasting does offer several benefits, it is also met with substantial scepticism and criticism. One significant risk pertains to medications, particularly for diabetes, wherein there is a requirement to adapt the dosage of the medicines. It is important to consult your doctor regarding any alterations in your medications as well as general lifestyle. The purpose of this article is to guide adults suffering from different health problems, such as obesity, as they would potentially enjoy several advantages that accompany intermittent fasting. However, we strongly recommend people suffering from eating disorders such as anorexia or those who are underweight, to refrain from fasting. This rule extends to pregnant women or those who are breastfeeding as well as people aged under 18.

What is intermittent fasting?

As a beginner, you may confuse intermittent fasting with starvation. However, they are two distinct concepts, with the primary differentiator being control. Starvation is not determined by choice. As it is an involuntary state that we are coerced into due to our circumstances, it may cause suffering or, in extreme cases, death. Conversely, fasting is a choice to abstain from consuming food, for a variety of reasons, typically centring on health and spirituality. Fasting is undertaken by individuals who have a considerable amount of stored fat, which is enough to sustain themselves. If done appropriately, fasting should neither lead to suffering, nor death. In simple words, you can access food. However, you choose not to. The period may vary based on your convenience- a few hours or even days. One can even exceed it up to a week or more, but only under medical supervision. The initiation and the conclusion of your fast are determined only by you. In simple words, at any point that you are not consuming food, you are on a fast. Technically, you are fasting between dinner and breakfast as well (unless you engage in midnight snacking). Therefore, our lifestyle already incorporates intermittent fasting. In fact, it is an age-old intervention and is extremely effective. If you break down the term breakfast, it is nothing but “break fast.” Therefore, that is a meal which breaks your fast and this happens every day. Simply put, the English language connotes that fasting is important in our daily routine and must not be considered a punishment or as something that is unusual. So, even if you perform it for a very short period of time each day, it is still a part of your daily routine. However, most of us tend to overlook the potency of this method in positively transforming our health. Moreover, familiarizing ourselves with the concept of fasting equips us with the power of choice.

Balancing eating and fasting

The most elementary principle of intermittent fasting enables our body to make use of the fat that is already stored in our body, thereby burning off some of our fat. It is crucial for you to understand that this practice is very normal and our bodies have adapted themselves to fast over short periods of time, which could be a few hours or days. This will not affect your health negatively. As most of you must be aware, our body fat is nothing but the energy from the food that we consumed, that is stored by our body. Thus, if we don’t eat our body will “eat” up the fat to obtain the required amount of energy. However, it is important to remember that we must live our life in moderation and attain the level of balance in whatever we do. This is relevant even when it comes to eating and fasting.

Let us not delve into the intricacies of this process.

Whenever we consume food, a substantial amount of energy is generated in our body. Although this energy is readily usable, some of it is stored to be used by our body later. The primary hormone that is used in energy storage is insulin.

Every time we eat, there is an increase in the amount of insulin in our body. Insulin helps our body store energy in two distinct ways. Initially, there is a breakdown of carbohydrates into singular units of glucose (sugar), with form long chains together called glycogen. Glycogen is stored either in the muscle or in our liver. However, when it comes to carbohydrates, there isn’t adequate storage space in our body. Thus, upon reaching the threshold level, glucose is transformed into fat by our liver, under the process known as de-novo lipogenesis (which means “making new fat”). While a small portion of this fat is deposited in the liver, the rest of it is exported to other areas of our body. Please note that the process is quite complex. However, there is close to no restrictions on fat generation within our body. In short, our excess food-based energy is stored in two ways in our body. Firstly, we have glycogen, which can be accessed quite easily by us, but the storage space for it in our body is quite limited. Then, there is body fat, for which there is no limitation of storage space. However, this cannot be accessed as easily.

When we refrain from eating, the process that unfolds is opposite in nature. There is a decline in the level of insulin, following which the body is notified to burn the stored energy. As there is a fall in the glucose, there is a need for the body to obtain glucose from the storage. As we have discussed already, the most easily accessible source of energy within our body is glycogen, which when broken down, results in glucose molecules, which provides energy. The energy that is generated in this fashion is adequate to run the body for about one day or more. Following this, the body fat is primarily broken down to obtain energy. In short, your body, in its most elementary form operates in two primary states. A state where it is fed and a state where it is being subjected to fasting. Therefore, we may either be storing food energy or burning it down. At any point of the day, one of the two is happening within your body. In case both of these aspects attain a balance, no change in the weight is observed. In case you start munching on food as soon as you get out of bed and do not take a break until you fall asleep, your body will continue to remain in the fed state for most of the time. Thus, with time, you may observe that you begin to put on weight as you didn’t allow your body to burn any of the fat stored. Thus, if you wish to lose weight, you must spend more time of a day enabling your body to burn the food energy, which happens with intermittent fasting. Therefore, the core principle of intermittent fasting is to help the body to use up the stored energy. To reiterate, this is not abnormal or unusual. Our bodies have been created in a manner that facilitates this process effectively. In fact, all animals are designed in such a manner. In case you consume food once every three hours, which is a system that is widely recommended, the food energy that is generated is instantly used up.

Benefits of intermittent fasting

As has been repeated throughout the article, the most commonly cited benefit of intermittent fasting is weight loss. However, we must not undermine the effectiveness of this trend by restricting its benefits merely to this. There are several other benefits that this system offers. In ancient times, the periods of fasting were commonly referred to as detoxifications or purifications, although conceptually, it is no different from intermittent fasting. That is because it was a popular belief that refraining from eating food would ensure that toxins are eliminated from the body. The health benefits associated with intermittent fasting include:

Loss of body fat
Increased burning of fat
A decrease in the level of insulin and sugar
Can potentially reverse type 2 diabetes
May enhance mental focus
A higher level of energy
May cause a rise in the growth hormone, even if only for a short period
Can potentially enhance blood cholesterol profile
May increase lifespan
Through stimulation of autophagy, cellular cleansing may be activated
Might decrease inflammation

Apart from the aforementioned list, fasting offers several other unique benefits that accompany fasting. It is important to note that most other “diets” tend to make life more challenging. However, fasting makes it much simpler as it saves time and is easy to practice anywhere.

How to practice intermittent fasting

Short Periods

Thankfully, there are no hard-and-fast rules when it comes to intermittent fasting. It is based on your discretion and you can alter the rules a little based on your convenience. Your periods of fasting may be short or long. However, if you plan on extending it beyond a few days, we strongly recommend seeking medical supervision. Typically, shorter fasts are preferred and they are performed more regularly.

16:8

This particular style of intermittent fasting requires the individual to fast for 16 hours per day. A few people also refer to it as an 8-hour eating window. All your meals must be consumed within the 8-hour window and the rest of the day must be reserved for strict dieting. This is typically done every day. For instance, all your meals may be consumed between 10:00 am and 6 pm. Therefore, this includes missing dinner. A few people eat dinner and miss breakfast instead. Within the 8-hour window, you may eat two or three meals.

20:4

As you may have guessed, with this method, you only have a 4-hour eating window while you fast for 20 hours of a day. Here, you can choose to eat anytime between 1:00 pm and 5:00 pm on each day, while you fast for the rest of the day. You may either consume a single heavy meal or two smaller meals.

Longer fasts (>24 hours)

24-hour fasts

In this, fasting may either be from dinner to dinner or from lunch to lunch. In simpler words, if you eat dinner today, your next meal will be dinner o the following day. So, you skip two meals on the second day. In simple terms, it is also referred to as “one meal a day,” or OMAD. People practice this diet only two or three times every week.

5:2 fast

Scientifically, this type of intermittent fasting was proven to have substantial merit, according to most studies. This particular type of intermittent fasting was explored in Dr Michael Mosley’s book ‘The Fast Diet.’ In this type of diet, an individual eats normally for five days and fasts on two days. On the two days of fasting, one can still eat about 500 calories per day. There are no restrictions in terms of time or the number of meals.

Alternate-day fasting

This is an alternative to the aforementioned approach, wherein every day is a fasting day, where you can eat 500 calories.

36-hour fasts

This approach requires the individual to fast an entire day. That is, if you eat dinner today, you do not consume anything tomorrow, and only eat again day-after morning, in the form of breakfast. That is, on one day, you skip all three meals. Technically, you are fasting for 36 hours. This method is more effective, as you do not have the choice to overeat dinner on the second day. But, the risks associated with fasting for more than 24 hours cannot be ignored.

Extended fasting

If you are eager to engage in extended fasts, you must first consult your healthcare providers and make sure that such fasts will not result in health complications for you. If you want to fast for more than 48 hours, I suggest consuming a multivitamin so as to ensure that you do not suffer from micronutrient deficiency. Interestingly, a person holds the world record for fasting for 382 days (do NOT try this!). Therefore, a few people may find it easy to fast for one to two weeks. I do not encourage fasting for more than 2 weeks as it may lead to refeeding syndrome, which is a change in fluids and minerals that may arise when food is consumed after a very long period. Needless to say, it is very dangerous. If you want a bespoke meal plan doing by me personally .. click here

Free guide: The Intermittent Fasting Guide

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