Everything You Need To Know About Fasting

In my previous post I wrote about the Winter weight loss challenge I'd set for myself and how I'd used fasting to help me lose 5.5kg in 28 days.

Following on from this I thought it would be pertinent to discuss fasting in more detail and articulate the associated benefits and drawbacks.

I first came across the concept of fasting for health specific reasons some 10 years ago after watching a documentary called Eat, Fast and Live Longer. I found it interesting and it resonated with me that bit more as the cogs of my own health and wellbeing evolution were already in motion. Prior to this I had thought of fasting as something that was done purely for religious purposes.

Fast forward a decade and fasting has become something I actively incorporate into my own diet.

At the end of this post is some bonus content highlighting my own personal experience of a prolonged fast. But before we get to this let's first understand some of the fundamental aspects of fasting...

What Is Fasting?

True fasting is essentially the process where one abstains from consuming food for a prolonged period of time. Although these days the term fasting has been repurposed to mean a significant reduction in the amount of food consumed over a given period of time. This has given rise to the term being used interchangeably with intermittent fasting.

There are several different types of fasting and intermittent fasting is perhaps the most well known. One of the most common intermittent fasting methods is time restricted feeding or time restricted eating. This involves refraining from consuming food for specific periods of time within a 24 hour window.

Examples of time restricted feeding include:

16:8

The consumption of food is avoided for 16 hours then permitted during the remaining 8 hour window. For example, you could eat your last meal at 7pm then not eat again until 11am the next day

20:4

In essence similar to the above but with an extended fasting period. For example, you could eat your last meal at 6pm then not eat again until 2pm the next day

OMAD

OMAD is an acronym for one meal a day and is quite literally the consumption of one meal a day

Another intermittent fasting method is the 5:2 diet where you would eat normally for 5 days and then restrict the amount of calories consumed on the other 2 days. On the 2 restricted days you would still be permitted to consume between 500-600 calories.

Alternate day fasting is another method of intermittent fasting and, as the name suggests, you would fast for 1 day then resume normal eating the next. This can be difficult to maintain over the long term however.

Prolonged fasts are a more extreme form of fasting that entail a total restriction of calories. They generally last anywhere between 2-5 days or up to a maximum of 2 weeks and only water, plain tea or coffee are permitted.

Dry fasting or absolute fasting is a subset of prolonged fasting where no food or liquids are consumed over a given period of time. This type of fast is considered the most extreme.

Two distinct advantages of intermittent fasting over prolonged fasting are the avoidance of severe feelings of hunger and the ability to practice daily.

Why Do People Fast?

There are a number of reasons why people fast but some of the more common reasons include:

Religious or Spiritual Purposes

Fasting is practiced in a variety of religions as a way to demonstrate devotion, humility and self-discipline. For example, Muslims may fast during Ramadan, Jews may fast for Yom Kippur and Christians may fast for Lent.

Cultural Traditions or Practices

Fasting is a common practice in some cultures such as those who celebrate certain events or holidays. For example Chinese people may practice fasting during the Lunar New Year.

Detoxification or Cleansing

People may fast to eliminate toxins from their bodies or to cleanse their gut.

Medical Procedures or Tests

A requirement of certain medical procedures, such as surgery or blood tests, may require that people fast. This ensures that the digestive system is empty and reduces the risk of complications during a procedure.

Mental and Emotional

People may fast for personal reasons such as introspection, to develop discipline or as a form of self-purification. Fasting may also be used as a way to demonstrate solidarity with a cause or community.

Health Reasons

Fasting is known to have various health benefits such as weight loss, improved blood sugar control and reduced inflammation. Some people use fasting as a tool to manage chronic conditions such as diabetes or high blood pressure. Fasting can also improve insulin sensitivity and promote the production of growth hormones.

Aesthetic Reasons

Fasting has become a popular tool to support fat loss. Fitness influencers, fashion models and celebrities have turned to fasting more and more to achieve a desirable, aesthetic look.

What Are The Benefits Of Fasting?

There are a number of reported benefits of fasting:

Improved Insulin Sensitivity

Fasting can help improve insulin sensitivity which is important for blood sugar control. This is due to the fact that fasting reduces insulin resistance which is a key factor in the development of type 2 diabetes. By improving insulin sensitivity, fasting can help to regulate blood sugar levels and reduce the risk of developing diabetes.

Reduced Inflammation

Inflammation is a major contributor to many diseases including heart disease, cancer and Alzheimer's disease. Fasting has been shown to reduce inflammation which may help to lower the risk of developing these conditions.

Increased Autophagy

Autophagy (pronounced or-tof-a-gee) is the process by which cells are conserved or recycled. Fasting can help to increase autophagy which is important for improving cellular health.

Improved Metabolic Health

Fasting has been shown to improve various markers of metabolic health such as blood pressure, cholesterol levels and body fat. When you fast for a certain period of time the body goes into a state of ketosis where it starts to burn fat for energy instead of glucose.

Increased Growth Hormone Production

Fasting can increase growth hormone production. As the name suggests growth hormone stimulates cell growth, reproduction and regeneration. This can help to promote muscle growth aka hypertrophy and improve overall body composition.

Enhanced Longevity

Some research suggests that fasting can increase one's lifespan. The reduction in oxidative stress and the promotion of cellular repair that fasting supports can help to improve overall health and increase longevity.

Hormesis

Hormesis is the term used to describe the way that cells and organisms respond to a moderate form of stress or adversity. Examples of hormetic stressors include saunas, cold plunges, high intensity workouts and fasting. Watch this short YouTube video for a better understanding of how fasting can support longevity.

In addition to the physical benefits, fasting has also been shown to have a number of positive mental effects:

Improved Mental Clarity

Fasting can aid mental clarity, focus and cognition. Some people report feeling more energetic, more task focused and demonstrate an increased capacity for understanding.

Improved Mood

Fasting can help to elevate one's mood and produce more profound feelings of happiness. Fasting may also help to combat depression.

Personal preference

Fasting is a personal choice. If you embark on this journey it's important to choose the type of fasting that works best for you and your lifestyle. Some people may find that they enjoy the benefits of fasting while others may find it difficult to adhere to. It's important to listen to your body and make adjustments as and when needed to ensure that fasting is a positive experience for you.

What Are The Drawbacks Of Fasting?

It's important to be mindful of the potential drawbacks to fasting, these can include:

Dehydration

Fasting can increase the risk of dehydration, therefore it's vitally important to hydrate regularly during a fasting period.

Health Conditions

Fasting can be dangerous for people with certain health conditions. People with low blood pressure, thyroid issues or those who are pregnant should refrain from fasting.

Hunger and Nausea

A prolonged fast can be challenging and may cause feelings of hunger, low energy and sickness.

Nutrient Deficiencies

One of the biggest criticisms of fasting is that it can lead to malnutrition and nutrient deficiencies, especially if performed over a prolonged period of time. For example, if a person only consumes water during a fast, they may not be getting enough essential vitamins, minerals and nutrients to maintain their health.

Disordered Eating

Another criticism of fasting is that it can lead to disordered eating patterns. Some people may develop an unhealthy obsession with fasting. This can lead to negative consequences such as binge eating, extreme food restriction or body dysmorphia.

Sustainability

Some people criticise fasting as they believe it's not sustainable as a long term strategy.

Lean Mass Loss

Whilst fasting can and does lead to a substantial loss of fat it can also lead to a loss of lean body mass. This loss can result in a reduced BMR (basal metabolic rate), a decline in neuromuscular function and an increased risk of injury

Mood

Fasting may cause headaches, fatigue and irritability. This can cause people to experience bad moods.

Re-feeding Syndrome

When breaking a fast it's quite possible to over eat, in extreme cases this can lead to re-feeding syndrome.

Breaking A Fast

The way you break a fast is as important as the fasting itself. It's extremely easy to overfeed which can have a detrimental impact to one's health.

The digestive system essentially shuts down during a prolonged fast. Stomach acids, bile and hormones such as insulin are effectively re-routed. Over time electrolyte storage and distribution is also affected.

Throughout a fast the body slowly switches to using stored fats and proteins as its main sources of energy. Reintroducing 'normal' food too quickly causes a sudden shift from fat metabolism back to carbohydrate metabolism.

Re-feeding syndrome is the term given to these notable metabolic shifts and is potentially deadly.

The best way to break a fast is to focus on easing the digestive system back to its original state. Soups, smoothies and soft vegetables are generally the best fast breakers.

Fasting Experts

In terms of expertise within the field of fasting it's difficult to single out one particular person as the most renowned. There are a multitude of proficient researchers who have made significant contributions to our understanding of the potential health benefits and risks of fasting.

Some of the more noteworthy people associated with fasting research include:

Dr. Valter Longo, an Italian professor of gerontology and biological sciences at the University of Southern California.

Dr. Jason Fung, a Canadian nephrologist and author who specialises in the treatment of obesity and type 2 diabetes.

Dr. Michael Mosley, an English physician, journalist and author who popularised the concept of intermittent fasting through his book "The Fast Diet".

Dr. David Sinclair, an Australian biologist and academic known for his research on ageing and epigenetics. Dr. Sinclair is also a professor of genetics at Harvard Medical School.

Conclusion

Fasting has become an interesting talking point in recent times and can be the subject of fierce debate.

Whilst the science behind fasting is growing, it's still a relatively new area of research and therefore more studies are required. However, the current evidence appears to be quite promising and supports the notion that fasting can be a safe and effective way to improve our health.

The effects of fasting can vary amongst individuals and what works for one may not work for the other. It's recommended that you consult with a healthcare professional before starting any fasting program, especially if there are any underlying health concerns.

As long as people fully comprehend all aspects of fasting, and as long as fasting is performed in a responsible manner I see no reason why it shouldn't be included in an individual's wellbeing toolkit.

For me fasting is a powerful tool that serves a number of different purposes. I'm mindful of the positives and the negatives, I've weighed these up and I'm comfortable with my own conclusions.

My experience of fasting has generally been positive.

Speaking of experiences... I did say at the beginning of this post that I would highlight my own prolonged fast - 72 hours to be precise. I'll talk about what was good, what was bad and ultimately what the results were.

Bonus Content - My Own Personal Experience Of A Prolonged Fast

I hope you enjoyed the post and the bonus content. Feel free to leave some comments below detailing your own experiences of fasting.

I'll leave you with a great infographic that summarises the key stages of a prolonged fast.

If you’re interested in improving your health then please do get in touch!

Michael East

ME LIFE