Intermittent Fasting 101

By September 13, 2020 October 14th, 2020 Health
Reading Time: 8 minutes

By Faye Hall

Intermittent fasting (IF) is a term that has gained popularity recently as modern living catches up with thousands of generations of fasting traditions and a natural reality of life for homo sapiens before we had food readily available to us 24/7. 

Humans are biologically accustomed and genetically predisposed to pass through life experiencing periods of fasting and feasting and states  of hunger and satiety. 

The mechanisms underpinning intermittent fasting potentially reflect how our ancestors ate and the historic and current religious practice of many millions of people.  

Yet modern life with widespread chronic disease, a very different food environment, new technology and unprecedented lifestyle challenges means that application of these mechanisms in this new context requires knowledge, skill and support between health professionals and their clients. 

There are many factors to consider when introducing this process. 

  • Pre-existing conditions that may need careful monitoring such as kidney issues or diabetes (type 1 and 2)
  • Use of medications and how these may interact with the fasting process
  • Ensuring adequate quality nutrition within a fasting window (a lost skill for many in our modern food culture)
  • The impact of hormonal changes in stress sensitive people
  • The impact on family and a person social context

Our weight loss programmes offer an easy and effective, supervised method for appropriately incorporating intermittent fasting into your lifestyle. 

When we first introduce our clients to the concept of intermittent fasting we are often met with wary looks about the thought of experiencing any level of hunger!

We are led to believe that if we allow ourselves to get hungry we might then eat out of control. A popular health message has been to “eat little and often”, but is this culture of grazing really true or valid advice? We might argue that these practices of frequent eating and snacking is one of the reasons why traditional diet programmes have left so many people unable to find a sustainable weight and eating pattern. 

Mild hunger, regularly experienced, far from being an undesirable state to be avoided or quashed at all costs is actually a perfectly normal and natural state of being that brings with it many benefits and should be part of our day, just as satiety is. Hunger is something to be embraced and enjoyed and our eating experiences may be significantly improved when we wait until we are properly hungry before eating, just as the French culture has practiced for generations with no snacks between meals.

It’s very normal and very human behaviour for us to seek out food and store fat, it is essential to have this bias because it has helped us survive for generations and ultimately still be on the planet today. It’s also very normal for us to be in a state of intermittent hunger and fasting and crucially still be able to perform well and feel good in this state. In fact in our clinical experience spanning many years we have had clients consistently reporting that they feel much better when following principles of intermittent living such as frequently fasting, more energy, a sharper mind, better sleep, better mood improved digestive function and healthy weight loss.

In this blog post we’re going to get into a little more detail about how and why intermittent fasting can impact your body and your mind positively, enabling a long term strategy for slender living. 

What is Intermittent Fasting? 

Intermittent fasting requires spending periods of time in a fasted state, typically this may involve overnight fasting (for more than 12 hours), calorie restricted fast days or eating within specifically designated time windows. 

A fasted state occurs when after a period of time of not eating or drinking anything except water. When we fast the way our body produces energy shifts from generating energy from food to generating energy from stored fat. 

This is the metabolic switch or flip that we often refer to here at Weight in Mind. It occurs when glycogen stores in the liver are depleted, (generally 12 hours after the cessation of food intake), and adipose tissue mobilises and releases fat stores to produce more fatty acids and glycerol. The free fatty acids are transported to the liver where they are converted to energy through beta-oxidation. Voila, a person becomes re-adapted to breaking down and burning fat as fuel rather than relying on a constant stream of food intake to service energy demands. 

There are numerous variations in methods of intermittent fasting and each person will require a slightly different approach depending on their goals. Some programmes allow black coffee and tea within the fasting period. 

The benefits of intermittent fasting vary depending on the person and their lifestyle and the type of fasting they do. Fasting has been shown to lead to weight loss and numerous health gains as we will outline below. 

At the heart of all the documented benefits of fasting is the concept of a hormetic response. The adaptive metabolic effect of short term fasting can be thought of as a positive stress or a “healthy stress” for the body. However achieving a healthy stress and all the benefits of fasting and taking care not to tip into a negative overall effect is key. 

Diagram 1  – Intake of “healthy stress” and health effect.

So getting the right “fasting prescription” is probably key. AND this will depend on a number of factors: pre-existing health conditions, amount of exercise, food intake, genetics, response to the different fasting methods, age, gender related differences, lifestyle and goals. 

Types of Intermittent Fasting We May Use in Our Clinic 

12 -12 -This is a twelve or more hour fasting cycle usually from late evening to early morning. This fast is great for beginners as most of the fasting-time is spent sleeping, so it is a great way to build up to a longer fast. The detriments of this fast are that the results may be limited this is more of an initial training in getting used to overnight fasting

Overnight Fasting:  16/8 -This fast has a feeding range of eight hours and a sixteen hour fasting window. It is a fasting method that offers flexibility as well as results as you can still get benefits and in our experience it is generally easy for people to implement and maintain.  This is not a regime to jump straight into. We recommend a supervised and gradual process of implementation with the support of an appropriate healthcare practitioner. 

18/:6 -This fasting method has an eating window of six hours and a fasting window of eighteen. It is much more rigorous than the 16:8 method due to its more restricted time window and can be a really effective weight loss tool. Graduates of the 16-8 who are well adapted to fat burning often comfortably end up here some days without even trying. However when doing this regularly there are some serious provisos to begin to consider. One example is that it does shorten the eating window which means careful meal planning to allow enough time and food to satisfy nutritional needs. In our clinic this kind of restricted eating usually comes with nutritional testing and monitoring, food based supplementation may be required more attention to dietary quality and variety is essential to success. 

20/4 – This method really reduces food intake to one meal a day or a 4 hour eating window. This more focused and intense fasting may have many potential benefits, however, also perhaps has more potential pitfalls. Engaging in this type of fasting in our view requires excellent body awareness and exceptional eating habits to optimise nutrition and an appropriate lifestyle to accompany the process.. This may not be suitable for most modern lifestyles. As a one off practice  rather than a way of living this method may have potential health effects particularly in relation to some specific  health conditions yet more research and clinical experience is needed.  We don’t currently recommend this directly to our clients. 

5:2 -This method is characterised by eating only 500 to 800 calories per day two days a week while eating normally the rest of the week. Some people combine this 5:2 method with an overnight fasting window to eat their 500/800 calories within a time restricted period.  We have never found it necessary to actively restrict calorie intake to this extent in order to get weight loss results. 

Intermittent Fasting Health Benefits

Health Benefits of IF are numerous. In fact the more we understand about the process the more convinced we are at Weight In Mind that after mindset training, this is one of the most useful measures a person can take in terms of initiating weight loss and maintaining an ideal weight. 

The Biological and Physiological Benefits 

  1. Improved response to insulin. 
  2. Management of healthy blood pressure.
  3. Anti-inflammatory actions in the body.
  4. Brain health and associated symptoms may also be improved due to the production of BDNF (brain-derived neurotrophic factor).
  5. Anti-ageing and autophagy. 
  6. Regulation of hunger signals. 

Find out about the full health benefits of fasting in one of our live online group courses and join our growing community of people safely fasting for health gains and weight loss. 

The Practical Benefits of IF 

With intermittent fasting there is less worry about the food you eat, fewer dishes to clean up as the number of meals are reduced, and less planning that needs to be done!

There is also flexibility, clients we work with find they are almost never de-railed from their process because then they can just adjust according to their life demands. A later night meal just means simply pushing your eating window back or forwards in order to include the designated fasting hours. 

Clients report food tasting better and that meals are more enjoyable. 

Client’s report feeling free, not being so focused and obsessive around food. We explain this by understanding that whilst fasting is a totally human experience, modern life has left many people “metabolically inflexible” and re-gaining metabolic flexibility and re-discovering the bodies ability to become fat-adapted and enjoy all the benefits that fasting offers is a wonderfully liberating experience and more balanced relationship  with food. 

Fasting provides a wonderful opportunity to up the ante on your nutrition. Due to the reduced eating window it becomes important to include appropriate nutrient dense foods in the diet to ensure individual nutritional needs are met. Psychologically clients report that they naturally seem to want to eat healthier and better and automatically seem to move towards healthier individual choices. 

In our clinic and courses we don’t leave those healthy choices to chance. We offer additional cookery tools, food education and nutrition knowledge, complete guidelines for what to eat and drink during a programme and in some cases nutritional testing and supplementation to correct deficiencies and enhance a person’s progress towards health and ideal weight even further. 

We believe food comes first and what we eat can be nutrient dense plant rich health promoting and delicious. To access a free our food plate and improve your food and nutrition knowledge sign up to our newsletter

Important Note

We believe It is important to begin making changes under the supervision of a healthcare care practitioner. This is especially so if you are on medication, or have pre-existing health conditions. Our programmes take a full case history and allow us to work with you and your medical doctor to ensure a safe and effective programme is offered. This information is not intended as advice it is intended to be educational and informative. 

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