Is the concept of ‘fasting’ – and perhaps even the word itself – too confronting to even think about, let alone contemplate doing? Does the thought of not eating automatically conjure up negative thoughts, such as hunger and discomfort?


We’ve become so accustomed to eating at every opportunity, on every occasion, with every emotion, for fun, for fuel, for boredom and when the clock tells us to.


If it does, you’re likely not alone and it’s not your fault. We’ve become so accustomed to eating at every opportunity, on every occasion, with every emotion, for fun, for fuel, for boredom and when the clock tells us to. But consider this: it hasn’t always been that way.

Let’s go back in time. Once, there were no clocks that indicated a prescribed meal-time. There were no ‘breakfast’ foods, ‘lunch’ foods, ‘snack’ foods, ‘supper’ foods’ or ‘dinner’ foods. There was just food – and it was eaten when available and not eaten when not available. Simple as that. Now, in the developed world, food is pretty much always available.


The science is telling us that periods of not eating are good for us.


For many, going without food today actually requires conscious effort. But here’s the good news: there is nothing about fasting to be afraid of, because it’s just not as hard as you think . . . if you do it right.

The science is telling us that periods of not eating are good for us. This is nothing new, really. Fasting was first mentioned in the Bible in 1500 BC – it was, apparently, mentioned 78 times, mostly for spiritual purposes. We now understand that fasting can help with weight loss, with preventing and improving chronic diseases, with allowing the body’s cells to repair themselves, and even with promoting longevity (living longer).

Before you get stuck in, though, it is important to work out whether fasting is for you given your specific circumstances and your goals – and, most importantly, whether fasting is not for you. So, we urge you to take our two fasting screening tests: the What the Fast!’ test and the Not so Fast!’ test. It is really important to take both of these tests. Fasting is not for everyone and, despite its potential health benefits, it can cause some people more harm than good, sometimes without them even realising it. So, you need to know if it is right for you before you buy in.


1. ‘What the Fast!’ test

Answer ‘Yes’ or ‘No’ to each of these 12 questions. For each ‘Yes’, score 1 point. For each ‘No’, score 0 points.

  1. Do you have unwanted body fat to lose?
  2. Do you have unwanted body fat that you just don’t seem to be able to shift?
  3. Do you sometimes eat when you’re not hungry? (i.e. out of boredom, happiness, sadness, celebrations and/or commiserations)
  4. Do you want to improve your longevity? (i.e. ‘live long, and healthily’)
  5. Do you want to be better equipped to minimise your risk of getting cancer?
  6. Do you want to get your blood sugar levels under control?
  7. Do you want to help regulate your hormones that control hunger and fullness?
  8. Do you want to improve your overall eating patterns and habits?
  9. Do you want to sharpen your mind and enhance your brain function?
  10. Do you want to strengthen your immune system?
  11. Do you feel like you need a detox?
  12. Do you eat more than 28 times in a week? (4 times a day)


Your score interpreted

Unlike most tests, where 6 out of 12, or 50%, is a pass, in this test 1 out of 12 is a pass. That’s because answering YES to just one of these questions means that you can benefit from fasting in some way. That’s a great start.


2. ‘Not so Fast!’ test

There are 6 questions. Again, answer ‘Yes’ or ‘No’ to each. For each ‘Yes’, score 1 point. for each ‘No’, score 0 points.

  1. Are you pregnant or breastfeeding?
  2. Have you ever had a history of eating disorders?
  3. Does your relationship with food cause you immense distress?
  4. Are you a type-A personality? (i.e. high anxiety, a stress-bunny)
  5. Are you a growing child?
  6. Do you have Type 1 diabetes, or a chronic disease that requires lots of medication, or a rare metabolic or genetic disease?


Your score interpreted

Interpreting the score on this test is a little more complex than for the first test. If your score is 1 or above, you should start hearing some warning bells relating to fasting. Let’s explain:


Question 1

If you are pregnant or breastfeeding, fasting is not for you right now. It’s unlikely to be harmful (because – let’s face it – the morning sickness you often get in pregnancy means that you end up fasting some of the time), but the goal in this phase of your life is to optimise calories and nutrients for your baby. Fasting might very well be for you at a later date, so put it on hold and come back to this later.


Questions 2 and 3

If you have a history of eating disorders or have an extremely volatile relationship with food (in that thinking about it causes you a serious amount of distress, beyond that which is considered normal), be wary of fasting. It could work for you or against you, so you need to make sure that you’re doing it for the right reasons. If you do try it, make sure you keep close tabs on whether and how your emotions/state of mind are affected.

If you feel confident about giving fasting a try, the best way to keep things in check is to ‘start low and go slow’. By this we mean getting your fasting- feet wet first by selecting an easy protocol to start with (i.e. missing one meal, like breakfast) and going from there. If you find that this is not having any negative impact, you can carry on.

Fasting might actually help improve your relationship with food, but if you find it having the opposite effect, then it’s just not for you. Of course, this requires that you be mindful and honest with yourself and others. You might need to seek professional help to figure this out. The last thing we want is to cause harm to you and your loved ones. This aim of this book is to help you achieve optimal health and wellbeing.



Question 4

If you know you are a stress-bunny in general, be extra-careful if you decide to pursue fasting. The reason is that when you fast, your stress hormone cortisol increases. While this is no problem for those who don’t suffer from anxiety, if you do then fasting has the potential to make things worse.

So it might be that fasting is not for you, or that you need to take smaller steps than what we’re suggesting in our Monday/Tuesday Super-Fasting method. Either way, the bottom line is to pay attention to how you feel, as you will soon work out whether fasting is or isn’t beneficial for you and your health, physical or mental.


Question 5

If you are a growing child (under 18 years of age), just focus on growing and enjoying eating a whole-food diet, keeping regularly active and enjoying life. If you miss a meal unintentionally, as kids often do, that’s fine – but leave purposeful fasting for later on.


Question 6

Not eating is a great way to get your blood sugar and your HbA1c (a measure of long-term blood sugar control) heading towards, and even achieving, normal levels. If you have Type 2 diabetes and are not taking insulin, then fasting should in fact be part of your management
plan. BUT when insulin is needed, it’s a different ballgame. While this doesn’t mean you can’t fast, it does mean that you have to be armed with the right information beforehand, and you need to be prepared to adjust your medication as you go. Ideally you should do this in conjunction with a supportive medical professional.

There are also diseases where fasting might not be recommended so talk to your medical professional before you contemplate fasting.


Your result

If you scored 1 or higher on ‘Not so Fast!’, then not so fast (literally) – do your homework, get the help you require to keep things well-monitored, and tread carefully.


So, what’s next?

Righto, for those of you who scored 1 or more out of 12 for ‘What the Fast!’ and 0 out of 6 for ‘Not so Fast!’, it’s a no-brainer – let’s get on with it.

Welcome to the Fasting Club!


This is an excerpt from What the Fast? by Caryn Zinn, Craig Rodger, and Grant Schofield.


Learn more

Explore the science behind fasting and understand how to put this into practice for yourself and/or your patients. Have a look at our short course PK203: Fasting: The Science and Practice


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