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Guide to intermittent fasting

Rachel Lett, ANutr

Head of Coaching


Intermittent fasting (IF) is a pattern of fasting and eating over a defined time period ⏰.

It is a powerful tool for reducing blood sugars, improving insulin sensitivity, reversing diabetes or PCOS, and generally improving your overall health. Recently it has gained a lot of support, quite simply because it works, and it’s easy.

In the article, I discuss eight practical tips to help you kick start, or improve your fasting game.


1. Choose the right fasting regime

Choose the right fasting regime that feels comfortable and fits with your lifestyle. It can be tempting to begin IF with an intense fast, but this will must likely lead to failure and discouragement. Instead, choose a fasting regime that feels manageable, and slowly increase your fasting window as you progress. There is no wrong or right way to fast, but the correct one will be achievable, long-term.

Take a look at our articles “7 types of intermittent fasting” and “ How to tailor fasting to your lifestyle”, to find your perfect fasting regime.

2. Be flexible

Life is flux, and everyday is different. Equally, your fasting regime should be flexible enough that it can mould around your daily schedule. Nothing is set in stone, and it’s completely fine to break your fast an hour earlier than intended — it won’t impact your results.

Giving yourself the liberty to fast according to lifestyle and how you’re feeling will most likely lead to better adherence. Simply being more mindful of hunger signals and noting when you start and stop eating is a gentle and effective way to introduce fasting into your daily life.

Rather than following intermittent fasting like a rule book, make it a natural extension that improves the everyday workings of your life. There’s something for everyone, so explore and have fun testing what works well for you.

3. Be clever with exercise

Fasting and exercise are complimentary of each other. Exercise enhances fasting benefits (autophagy, glucose clearance etc.) and can improve your fasting regime— it keeps your mind off food and acts as an appetite suppressant. at the same time, fasting improves exercise performance and results.

With that said, exercising in the fasted state can be challenging if you’re not fat adapted — this is when your body can efficiently use fat for fuel. It will take time for your body to adapt to your new fasting regime,  and thus transition into a ‘fat burning machine’.

Keep this in mind if you’re struggling to continue your usual exercise  regimen while you fast. Begin with manageable, low-intensity exercise and slowly build up.

4. Stay hydrated & replace electrolytes

Electrolyte and water loss is a common and normal response during intermittent fasting. If you don’t replace water and electrolytes, you will experience headaches, fatigue, increased hunger, dry mouth, muscle cramping, nausea and light headedness. In other words, you will feel horrendous — dehydration would be enough to make you throw in the fasting towel.

Fasting does not mean “Nothing can pass my lips. No water. No anything. Ever”. Your body will not do well if you restrict fluids and electrolytes, so make sure you drink plenty and replace essential minerals. Here is a guide on “What to drink while intermittent fasting’ and "Electrolytes" to help you hydrate.

Water requirement is based on your weight and activity level. Check out this website to calculate your personal water requirement and try to aim for this, daily.

5. Eat low-carb, high fat

What you eat, is just as important as when you eat. Remember that intermittent fasting is not a passport to eat poor quality food. Rather, use it to get the most out of your diet and health.

We recommend you stick to high quality, low carbohydrate, high fat and moderate protein meals in-between fasts. This will stabilise blood sugars, promote satiety, and make fasting run that little bit smoother.

‍For whatever reason you are doing intermittent fasting, a high fat, low-carb diet will enhance your results, helping you reach your health goals, faster.

6. Break your fast slowly, with fat and protein

It’s tempting to break a fast with a feast, but this can cause fatigue and an upset tummy. Ease into your eating window with a small meal like homemade bone broth, then have a normal sized meal an hour or so later. Gut loving bone broth will prep your digestion and tame hunger so you won’t be tempted to eat everything in sight.

Breaking your fast with carbohydrates or too much protein can flood your system with glucose, causing you to feel tired. Eat a low carb meal that is high in fat and moderate protein

7. Eat enough Protein

Intermittent fasting has a natural tendency to put an individual in a calorie deficit and cause weight loss — fat loss is good, but muscle loss is bad.

To prevent muscle wasting, you must meet your protein requirement. This can be challenging when there are less meals, and windows of opportunity to eat protein throughout the day. If you are failing to meet your protein requirement, try supplementing with a low-carb protein powder

8. Track your results and use a fasting tracker

Whether it’s body composition, mood or blood glucose levels, keep track of your progress. Even the small wins are worth jotting down.

These quantifiable records will give you instant feedback on your progress, and naturally motivate you to keep going or “get back on track”.

Use a fasting tracker like Zero or LIFE. These useful  apps will keep track of your fasts, provide motivation and keep you accountable.

Intermittent fasting has a profound effect on health, so most importantly, don't give up too soon — you won't see the full spectrum of possibilities if you only try it for a day or two. Use this guide to help you stay on track so you give your body time to adjust — your body has the capability to feel outstanding!

Like what you’re hearing?

Stay tuned for more guides, to help you with your health journey.

Take care,

I’m sure you’re curious about the science behind all this 🔬 Here are some recent medical publications about this topic:


September 15, 2021
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