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Intermittent Fasting: The Do’s and Don’ts

Intermittent Fasting

Here’s the lowdown on Intermittent fasting.

By now, you’ve probably heard about intermittent fasting (IF) as a new way of achieving weight loss, improved concentration and other health benefits.

So, is this just another fad diet OR is this the answer to reaching sustainable weight loss goals, boosting brain function and optimising your health?


Let’s take a look at what the research says.


What is intermittent fasting (IF)?

Intermittent fasting is an eating plan that alternates between allocated periods of fasting with periods of eating. Its popularity stems from its reputation for breaking through weight loss plateaus and burning fat, but there’s a lot of research which also supports its use in other areas! (Keep reading if you want to know more!)

There are many variations of IF which range from fasting for 24-36 hours twice weekly or a more regular routine where you eat in an 8-hour window (for example eating from 10am-6pm, then fasting from 10pm-6am).


So, how does IF work?

Let’s firstly take a look at what happens to your body when you eat:

  1. Depending on what you’ve eaten, your blood glucose (sugar) levels will increase.
  2. Your body strives to maintain balance, aka homeostasis. When it notices this increase in blood sugar levels, it sends a message to the pancreas to produce a hormone called insulin.
  3. Insulin is released which tells your cells to open their ‘doors’ and take in that glucose from the blood so that the blood levels normalise and your cells are fuelled with glucose.
  4. Your body then releases hormones like leptin, which tell your brain ‘Hey I’m full, stop eating’. So, these hormones are crucial for regulating your appetite.

However, if you are eating a diet high in processed carbohydrates and sugars – your body produces lots more insulin and leptin. The more you produce; the more ‘numb’ your cells become to these hormones. This can lead to insulin resistance. Chronically elevated leptin and insulin can put you at risk of chronic diseases such as Type 2 Diabetes, high blood pressure and elevated triglycerides. In these cases the sugars in your blood remain abnormally high, and also cause your body to store more fat and reduce your ability to tell when you are full.

So instead of eating the typical Western diet of 3 meals and day plus snacks, the period of fasting in IF allows your body to lower insulin and sugar levels, which reverses the fat-storing process. Instead, your body goes looking for fuel sources to burn as it is not getting energy from external foods/drinks. Firstly it pulls stored sugars, then it turns to stored fats and burns these for energy. This is called metabolic switching. This fat burning has been shown to have many health benefits for weight loss, brain health and much, much more (see below).


Potential benefits of IF:


Weight loss:

IF can lower your insulin levels which reduces fat storage. and also increase the leptin ‘I’m full’ hormone which means you feel fuller faster and hungry less often. This could result in fewer calories consumed and, as a result, weight loss.

Brain Health:

Intermittent fasting has been used as a powerful therapy to assist brain healing, and also to improve concentration, memory and cognition


Restricting calorie intake has been long researched to be the most effective way known to increase lifespan, and intermittent fasting creates the perfect conditions for this to happen. Fasting allows your cells to detox, repair, and recycle, so it not only slows aging, but also heads off age-related diseases.

Heart health:

IF has been shown to reduce the concentration of total cholesterol, triglycerides, and LDL cholesterol- hence reducing risk of cardiovascular disease. This is largely because the body switches to using fat for energy, when fasting which includes using cholesterol and triglycerides- hence lowering their amounts in the body. Also, the anti-inflammatory benefits of IF is suggested to also play a role in reducing heart-related diseases.

Physical performance:

In a study, young men fasted for 16 hours and showed fat loss while maintaining muscle mass as a result. Also, mice who were fed on alternate days showed better endurance in running. This suggests that there can be beneficial effects on increased performance and muscle mass when doing IF. However, other studies looking at soccer player’s performance when fasting from dusk-dawn showed decreased strength, energy and muscle mass. Therefore, more research is required that look at the different types of IF and other variables.

Fights Cancer:

Fasting has been shown to help prevent cancer and even slow or stop its progress. It can also kill cancer cells, and boost the immune system!

In addition to the amazing benefits described above, intermittent fasting can also boost energy and mental focus, increase insulin sensitivity, and reduce the risk of cardiovascular disease.

Fasting is NOT for everyone

Not everyone does well on a fasting plan. In general, women should proceed with caution because we tend to do better with a regimented eating schedule. Pregnant women should never attempt to fast due to the needs of the growing infant. And those who have infertility issues should also take a pass. Also, those who have have adrenal/cortisol issues or are prone to low-sugar levels should speak to a practitioner before jumping on the fasting bandwagon. 

Tips for successful fasting:

To get many of the benefits of intermittent fasting without the deprivation and starvation, start with a simple 12-14 hour fast:

  1. Start by having breakfast 12 hours after you last ate the previous night, e.g. if you had dinner on Monday at 7:30pm, then have breakfast on Tuesday morning at 7:30am. You can extend your fast to 14 hours when you feel comfortable.
  2. Strategies to avoid hunger cravings AND to stay hydrated include drinking generous amounts of water or other healthy, low calorie options like coffee, green tea, or bone broth. Most research recommends nothing containing over 50 calories as more than 50 calories will break your fast and shut off fat burning.
  3. Drink water to stay hydrated! You are fasting from calories, NOT water so keep hydrated – aiming for an average of 2L a day
  4. Aim to stop eating at least 3 hours before bedtime so you have sufficient time to digest your dinner
  5. Choose a low-stress day to fast (e.g. the weekend). If possible, get away from your food triggers, plan time away from home, and make sure you’re staying hydrated which will keep cravings to a minimum (as mentioned above, nothing over 50 calories)
  6. Break your fast with a nourishing, balanced meal (approximately ½ plate veggies, ¼ protein, ¼ wholegrains carbs/plant fats) – ensure that you DON’T grab a sugary/ processed carbohydrate-based meal or snack. It will simple spike your insulin levels!
  7. If you need a snack between meals- reach for a high-protein, high fibre option. Avoid carbohydrate-based, sugary snacks and drinks that will spike your insulin levels, which prevents you from using stored fat for fuel and encourages your body to store fat. Good snack options include; mixed nuts and seeds, sugar-free natural protein bar, 1-2 boiled eggs, hummus + veggie sticks, seed crackers, roasted seaweed snacks, DIY protein ball, or a natural protein/collagen shake.

This plan creates an automatic 12-14 hour fasting window – mostly while you’re asleep!


“The above information is for information purposes only. It is not designed to treat, cure or prevent any condition. Please consult with your health care professional before making any changes to your current lifestyle. If you are seeking personalised holistic and expert health advice- contact one of our Health Squared Naturopaths, Dietitians and Nutritionists at: