Intermittent fasting... is it for you?

March 12, 2018
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Intermittent Fasting (IF) has been receiving a lot of attention lately, so you may be wondering what it's all about, and if it's just another new diet trend or fad.

In truth, intermittent fasting is nothing new at all. It's actually been around ever since humans have existed on earth. Not only did our ancestors spend long periods without food due to a scarcity of supply, but there were (and still are) religious observances which involve fasting for extended periods.

So what's changed? Why the sudden hype? We're hearing a lot more about it due to recent strong scientific evidence which supports the effects IF has on our bodies. The data has revealed an impressive list of benefits for those seeking to improve not only their body composition but their actual health, well-being, and longevity (and who doesn't want that?). Check out this list:

  • A reduction in LDL cholesterol (that's the bad one) and triglycerides.
  • A lowering in blood pressure.
  • A reduction in inflammation in your body.
  • Your risk of cancer is reduced.
  • Cells regenerate and repair faster.
  • Fat burning is increased.
  • Growth hormone levels are increased (which helps with body composition, building muscle, and sugar and fat metabolism).
  • Metabolism is increased.
  • Appetite control is improved.
  • Blood sugar is controlled.
  • Cardiovascular function is improved.
  • Anti-aging – you may live longer (and who doesn't want that?).

Of course, in reality, everyone fasts to a degree as there is usually a ten to twelve-hour window between your dinner and breakfast. Any longer than that is much easier said than done, and it may not be for everyone.

There are three currently popular types of fast.

Two low-calorie days per week, aka Dr. Michael Mosley's 5:2 diet

The 5:2 diet is the one where you pick two non-consecutive days of the week on which to consume 500 calories for women and 600 for men (roughly 1/3 of your regular daily calorie intake). The rest of the week you can eat "normally, non-restrictively," although it does need to be healthy. You do need to plan your low-calorie day ahead, and weigh/measure everything you eat. You should also be prepared to feel quite hungry the first time you try it. Here's an example of what a 500-600 calorie day could look like: 1 poached egg with 1 cup vegetables, a piccolo, and 80-100g fish with vegetables or salad. Not bad if you're a busy person who is constantly running around, but if you're used to having 3 meals and 2 snacks per day, this can be a massive adjustment. That said, if you're familiar with calories, are determined and have tried and failed with other weight loss methods, this might be for you.

The 16/8 fasting method

If you don't like the idea of the 5:2 method, the 16/8 approach might be for you. This involves a fast for 16 hours, followed by an 8-hour window during which you can eat. So if you ate dinner at 8 pm last night, you would not eat again until 12 pm the next day. However, the simpler method and best results are obtained if you eat dinner by 5-6 pm and then breakfast at 9-10 am the next day. Much easier to stick to and great for those who work in offices or on shifts and can eat a light meal at work. Please note, however, that confusing your mouth with a vacuum cleaner during the eight hours is counter-productive, so cramming as much food in as possible during the window would probably not achieve the outcome you are hoping for. Again, it's best to eat nutrient-rich foods such as proteins, vegetables, fruits, dairy, and whole grains during your "feeding window."

The 24-hour fast

Exactly as it sounds, you go without food for 24 hours once or twice per week. During this time, you may drink water, black or herbal tea, and black coffee, but otherwise, it's nil-by-mouth. On non-fasting days, you eat "sensibly," meaning a higher protein diet with an emphasis on nutrient-rich foods (in other words from mother nature and not processed or out of a packet). The benefits are that not only can you choose which days to fast, but also the start and finish of the 24-hour period. So, for instance, you could eat breakfast on Monday, and then not eat until breakfast on Tuesday. Not recommended if you have a physically active job unless you do it on a weekend.

So which do we recommend?

This depends on what works for YOU, and which you can fully comply with and sustain over time. It's also worth mentioning that intermittent fasting methods do not mean that you can eat junk food in your eating windows and still reap the benefits – attention must be paid to getting the proper balance of proteins, carbs, and fats.

Another major consideration when thinking about which method to go with is how active you are. If you're a regular exerciser, have a physically active job, or are a busy mum running around after the kids, working, and going to the gym, you'll have a higher requirement for food intake than those who don't exercise and sit at the computer for most of the day. If this is you, you'll likely be hungrier and will find yourself getting tired, cranky, and experiencing major hunger pangs or cravings if you cut back too drastically. That's why we recommend the Deficit Day System (created by The Boutagy Fitness Institute), and have had great success using it with our Coastal Bodies challenges.

The Deficit Day System

The Deficit Day System has a higher compliance than the 5:2 diet because the caloric intake is slightly higher (approximately 1/3 of your daily requirement), and factors in your activity levels, height, age, and whether you're male or female when calculating your caloric intake.

The other significant difference is that on your Deficit Days (twice a week), you must train with weights in order to "rescue" any muscle that could be lost. If you don't do weights on your Deficit Days, you risk losing a large percentage of your weight from muscle, not fat – the exact opposite of what you want to achieve. In combination with the higher protein intake of the Deficit Day System, this helps ensure you lose fat, and not your muscle!

For more information on the Deficit Day System, please contact us on

Happy fasting!


  • Dr. John Berardi, Precision Nutrition
  • Susie Burrell, SmartShape
  • Tony Boutagy, The Boutagy Fitness Institute

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