Intermittent Fasting… it became a Health & Fitness buzzword a few years ago, but does it actually work for Fat Loss?
Yep!🙌🏻
And Nope…🤔
What is Intermittent Fasting?
Intermittent Fasting (‘IF’) is not a ‘diet’
It is a Meal Timing Strategy, or Eating Pattern, which cycles between a period of eating and period of Fasting.
[Allaf et al nicely explain the various types of IF under the section ‘Description of the intervention’ in this paper: www.ncbi.nlm.nih.gov/pmc/articles/PMC8092432/ ]
How can you do it?
IF is typically adopted for Fat Loss like this…
⌚You might set yourself an extended period of time during each day where you do not eat any food, say 8pm until 12pm/midday the following day.
🥙Allowing yourself an ‘Eating Window’ of around 8 hours the next day from midday to 8pm.
✅=16 hours of Fasting (which includes your sleep!😴) with an 8 hour window for Eating.
So let's say you want to eat 500 Calories fewer per day, this could be much easier to achieve by removing a typical breakfast or meal on those days!
Important to Note about achieving Fat Loss...
In order to lose excess body fat, one must be in a Calorie Deficit for an extended period of time, to prompt the body to utilise that stored fat as energy.
Essentially - eating less energy (in the form of food) than energy you output (in the form of moving, living and breathing!).
Consistently maintaining a Calorie Deficit for a long enough period to lose fat can be quite challenging, so finding a way to simplify things can be helpful…
Intermittent Fasting might be that thing, but it needs to fit your lifestyle and preferences. If you are fighting an urge to eat breakfast to do this, it may not last long, and success is unlikely!
Similarly, you need to consider other aspects for success with Fat Loss, such as adequate Protein and Fibre, total Calories, Exercise and Activity, Sleep Quality, Hydration etc (more on those topics in my content).
Potential Benefits of Intermittent Fasting
IF can help you:
Plan your food better
Eat larger (but fewer) meals
Limit Calorie intake (Fat Loss)
Have less meal-preparaion and tidying up!
Stop you 'picking' or randomly snacking on high-calorie items
IF has been shown in various studies that it could:
Aid growth of new nerve cells in the Brain
Deliver positive outcomes for Fat Loss
Reduce the risk of type 2 diabetes
Lower Inflammation markers &;
Reduce risk of heart disease
Reduce risk of cancer
…it may even help you to live longer.
Research is still in early stages however.
*Several Studies linked below📌
Potential Problems with Intermittent Fasting
IF is not without its potential problems though…
It can give you a false sense of security, allowing you to think you can snack on high-calorie foods safely because you’ve effectively dropped a meal.
This could lead to eating in a Calorie Surplus and further weight GAIN if not monitored.
It can also cause hunger if you take it too far the other way, eventually leading to a BIG relapse / binge / or period where you throw all food control out of the window completely!
It may exasperate established Eating Disorders, or create one in those more prone to strong addictive behavioural triggers or patterns.
For non-obese people, it may have a negative effect on blood sugar control and /or insulin sensitivity - so consider some blood work prior and during IF to check.
If you have any of the following, you should consult a doctor before commencing with IF or get some private blood work and analysis done with a professional:
Any history of Eating Disorders
Blood Sugar regulation issues
Pregnant or Breastfeeding
Female trying to conceive
Low Blood Pressure
Taking medications
Are Underweight
Diabetes
However IF has a good safety history, and if you are generally Healthy and Well Nourished, it is not dangerous to go without food for periods of Fasting.
Have you tried this method for Fat Loss? Any tips on how to make it work? Pop your thoughts in the Comments…
FAQ's:
Can I drink liquids while fasting? Yep! Water, Coffee, Tea and non-Caloric drinks are fine. You can include a little milk or cream as well
Can I take Supplements whilst fasting? Yep! Just be mindful that some are best taken with foods, so you may need to adjust your timing.
Can I work out whilst fasted? Yep! If you are fasting for long periods (like whole days) then you might want to go easy on volume or intensity as you adapt.
Will Fasting Cause Muscle loss? Not in and of itself… however if you are not eating enough total protein and/or don’t lift some weights, then you might have muscle loss (same as any ‘diet’ choice)
Is it ‘unhealthy’ to skip the “most important meal of the day” (breakfast)? Nope! You can still adopt and maintain a healthy diet and lifestyle whilst incorporating IF.Will fasting affect my metabolism? No… Some studies show IF can boost metabolism, however fasting for long periods can reduce it.
Will fasting affect my metabolism? No… Some studies show IF can boost metabolism, however fasting for long periods can reduce it.
📌Studies:
Unravelling the health effects of fasting: a long road from obesity treatment to healthy life span increase and improved cognition - Toledo et al June 2020: www.ncbi.nlm.nih.gov/pmc/articles/PMC7877980/
The Effects of Intermittent Fasting on Brain and Cognitive Function - Gudden et al Sept 2021: www.ncbi.nlm.nih.gov/pmc/articles/PMC8470960/
Cardiometabolic Benefits of Intermittent Fasting - Varady et al Oct 2021: pubmed.ncbi.nlm.nih.gov/34633860/
...and a brand new review paper which analyses LOADS of research in one place:
Intermittent fasting for adults with overweight or obesity - Garegnani et al Sept 2023: www.ncbi.nlm.nih.gov/pmc/articles/PMC10485895/