When it comes to choosing which topic to cover in our blogs I tend to try and think of what our clients are talking about and asking us about the most.

Today’s topic certainly comes into this bracket. On an almost weekly basis at the moment we are being asked “I am thinking of trying the intermittent fasting diet, what do you think of it?” And like most things my answer is, it depends…

Like most diets intermittent fasting can either be a great thing for many people, for some it may be a disaster and for others it might be somewhere in the middle. Hopefully after reading this blog today you can decide which one it is most likely to be for you.

Fasting is not a new phenomenon, people have been fasting for 100’s of years for both religious and health reasons. There are many different versions of fasting ranging from 16 hours fasts with 8 hours feeds; or full on 24-72 hour pure fasts (just drinking water). The 5:2 diet which is eating low calories two days per week than normal, the other 5 is another variation of a fast. At the moment the most popular seems to be the 16:8 fast.

Personally I was pretty sceptical of fasting due to the fact my early days of learning about nutrition were all based around the ‘eat small and often’ mantra and that if you don’t eat regularly you will slow your metabolism down and lose muscle. However over the past few years I have been reading and hearing a lot of more up to date research on fasting showing that it can be a great tool for losing weight and for promoting better health. The final contributing factor for me on deciding to try it myself came when one of our clients who is an oncologist was telling me how they are now using it as part of a treatment plan for cancer patients and also advocating it as a way to reduce your cancer risks.

So at the tail end of 2019 I thought I would try the 16:8 diet as it seemed the easiest to implement.

I would simply stop eating after my evening meal and then not eat again until around 11am the next day . I went into this thinking that I was going to find it very difficult, however I was pleasantly surprised when after a few days of fasting all I would get was a very mild rumbling of hunger for 5 minutes or so or so which would then go away. I would then easily go 12-16 hours per day without food and manage to not go too crazy when I finally did eat.

When following the intermittent fasting diet I did lose weight but one of the biggest things I noticed was that I had much more energy and had a lot more focus and felt more clear in my though processes.

It also taught me both physically and mentally that I didn’t need to eat as often as I thought I do and to not rush to the kitchen at the first sign of hunger I have. So going forward I will certainly use it sporadically as a way to control my calorie intake at times when I am looking to trim down a little. Hopefully it will contribute to increasing my chances of good health for many years to come. I have been back to eating normally over winter to try and build some muscle and I have certainly felt that my energy levels are not as consistent as when I was fasting.

This is all obviously just my personal experience with fasting, however there is lots of research and materials out there to inform your decisions. Here are the highlights of what I have found so far.

Health Benefits

Weight loss – A 2017 study suggests that intermittent fasting leads to greater weight loss and fat loss in men with obesity than regular calorie restriction.

Research from 2016 reports that men who followed a 16:8 approach for 8 weeks while resistance training showed a decrease in fat mass and what was interesting was that the participants maintained their muscle mass throughout (I would however suggest that if you are looking to build muscle I would not combine the two as you will find it difficult to build muscle in a calorie deficit).

A 2018 study indicates that in addition to weight loss, an 8-hour eating window may help reduce blood pressure in adults with obesity.

When fasting the levels of growth hormones skyrocket, increasing as much as 5-fold. This has benefits for fat loss and muscle gain, to name a few.

Research is indicating that fasting may enhance disease prevention in the following conditions

  • Type 2 Diabetes
  • heart conditions
  • some cancers
  • neurodegenerative diseases
  • Time-restricted fasting, such as the 16:8 method, may also protect learning and memory and slow down diseases that affect the brain. 
  • Heart health: Intermittent fasting may reduce “bad” LDL cholesterol, blood triglycerides, inflammatory markers, blood sugar and insulin resistance — all risk factors for heart disease 
  • Inflammation: Some studies show reductions in markers of inflammation, a key driver of many chronic diseases

Some Cons to Fasting

  • Potential of hunger, weakness, and tiredness in the beginning stages of the plan
  • Overeating or eating unhealthful foods during the 8-hour eating window due to excessive hunger
  • Heartburn or reflux as a result of overeating
  • Individuals with a history of disordered eating may wish to avoid intermittent fasting. 
  • The 16:8 plan may also not be suitable for those with a history of depression and anxiety. Some research  indicates that short-term calorie restriction might relieve depression but that chronic calorie restriction can have the opposite effect. More research is necessary to understand the implications of these findings.
  • 16:8 intermittent fasting is unsuitable for those who are pregnant, breastfeeding, or trying to conceive.
  • Also, keep in mind that the main reason for its success is that intermittent fasting helps you eat fewer calories overall. If you binge and eat massive amounts during your eating periods, you may not lose any weight at all.

There is some evidence that intermittent fasting may not be as beneficial for women as it is for men. For example, one study showed that it improved insulin sensitivity in men, but worsened blood sugar control in women (Trusted Source).There are a number of anecdotal reports of women whose menstrual period stopped when they started doing IF and went back to normal when they resumed their previous eating pattern.

My final personal thoughts on intermittent fasting

I have always been interested to observe how at certain times of the year people can magically stick to habit changes they have set on themselves such as no chocolate for lent, or sober for October/dry January. They struggle to stick to making the changes the rest of the year, but suddenly when they set a hard and fast rule like this they can somehow do it with little to no slip ups.

Perhaps this is a way that fasting can work, for example if you say I am not going to eat after I finish my dinner you take away the battle of eating in the evening and you just stick to it (and from experience with clients it is the extra calories that we do not need in the evening that tip us into a weight gain cycle).

So as I say like every other diet Intermittent Fasting is certainly not for everyone, however it does seem like there is growing evidence that it can be a healthy way to eat for many people.


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