Food & Nutrition

Keto Fasting

Keto Fasting

Want to know the awesome benefits of fasting and how you can integrate it with your life? Read on…

Who You Gonna Call? Myth Busters!

First of all we need to clear-up a common myth/misconception about fasting. Fasting is not starving, they are very different. Starvation is when your body does not have enough nutrition to meet its needs. During times of starvation the body starts to break down muscles and other tissue to get emergency fuel. When we’re aiming for keto, this is not what we want!
During ketosis we always ensure the body has enough nutrition to meet its needs, even when you are losing weight it is still important to ensure the body has enough macronutrients. Fasting, on the other hand, is limiting the amount of time spent eating. The body still gets the same amount of nutrition to meet its needs. But, this nutrition is provided during at specific times, called “feeding windows” which maximize the benefits of nourishing your body.

Benefits of Fasting

So, now you know fasting is not the same as starving let’s look at why you might want to do it. There are many benefits to fasting which fall into the following categories: hormone control, enhanced weight loss, convenience, disease prevention and life extension.
All of these benefits are a result of one simple fact, that the human body is not suited to constant grazing. In fact, the body prefers to have long periods of time spent not eating.
When we eat the body has to concentrate on dealing with the incoming food. It has to provide enzymes, energy, blood and a lot of effort into dealing with the food we eat. When it is dealing with food, a lot of other essential processes go on ‘standby’.
This is one reason why eating a big meal makes you sleepy as blood and energy is diverted to digestion. But, there are a lot of other tasks the body needs to perform in addition to eating. It needs to remove waste products, repair damaged cells, make new cells, protect the body and generally keep things fit and healthy.
When we eat throughout the whole day, the body simply doesn’t have the time, metabolic signals or resources to perform all the essential maintenance work to keep us healthy. Imagine throwing a 24/7 party while trying to spring clean your house, it’s just not going to work. You need to stop the party, then clear up, then you can have another party if you want. It’s the same with your body: it needs time to fully process your food, and, crucially time without food to properly maintain you!

Hormonal Changes

Regularly giving your body time without food, for example finishing your last meal at 6pm and not eating again until noon the next day, has a significant impact on your hormones:
  • Insulin sensitivity is improved, which reduces the risk of diabetes, lowers blood sugar and reduces appetite
  • Leptin sensitivity is improved, which also reduces hunger and boosts metabolism and fat burning
  • Ghrelin production is increased which increases feelings of satisfaction after eating
  • Human Growth Hormone (HGH) production is increased, promoting general wellbeing and longevity
  • Prolonged and regular periods without food help your body adapt more quickly to burning fat.
The combined impact of these hormonal changes means weight loss becomes even easier. Reducing the number of hours eating reduces both physical appetite and also mental appetite.

Less Eating, More Time

The mind and body easily adapt to expecting food during specific windows of time. This means you will think less about food and also have less hunger during your fasting time. Intermittent fasting, with a feeding window of 6 to 8 hours, will even help you lose weight all by itself. In fact some studies show fasting is the best way to lose fat without losing lean muscle mass .
During fasts, fat oxidation is increased, meaning your body is more effectively burning it off. Fat adaption, which is teaching your body to use the fat it has stored, is also increased. This means you will start to lose weight quicker and your body ‘wants’ to get rid of it. People also typically find intermittent fasting quite easy, so they are able to stick with it. Combine this with calorie restriction and you can see why weight loss is enhanced so much by fasting.
The next big benefit is simply the convenience of not having to eat! While food can be a lot of fun, it can also be a pain having to prepare and eat 3 meals a day plus snacks. The time, energy, effort, washing up and calorie consumption can all be reduced by simply eating less often.
Putting your effort into just 2 meals during your feeding window frees up at least a 5 hours a week! When you have a reduced appetite, and your nutritional needs are met, there is no sense in forcing your body to eat when it doesn’t want it or need it. Fasting is very flexible and there are a wide variety of options to choose from which can meet the demands of your schedule and your personal preferences

Life Saver

The next major benefit is disease prevention and life extension. Who would have thought that simply eating for less time would prolong your life?! Intermittent fasting has even earned itself the title of the ‘fountain of youth’ due to its stimulation of Human Growth Hormone which usually reduces as we age.
In fact, food restriction, is the only scientifically proven way to extend lifespan and prevent aging. During the fasted state the body has the resources and focus it needs to repair your body. Fasting specifically increases a process called autophagy which is when the body maintains itself. It is also able to remove toxins and waste products more efficiently.
Typically sleep is improved and you have more energy when you fast. Studies show that fasting reduces the risk of several diseases, including cancer, diabetes, metabolic syndrome, cardiovascular disease and it reduces blood pressure and inflammation.
While these benefits might seem ground-breaking, really they are all just saying the same thing. Humans do not need to eat as much, or as often, as advertisers would like us to believe!

Practical Fasting

How you could fasting fit it into your life? Just like the keto diet, intermittent fasting is very flexible and should be done to suit your needs. Here are some fasting patterns you can consider:

Skipping Meals

Just choose some meals to miss when you feel less hungry or it isn’t convenient for you to eat. Maybe you could get an extra hour in bed by missing breakfast. You could do this occasionally or everyday, depending on what works for you. You can experiment with this concept, and on a day to day basis just ask yourself, do I want to eat or not. You may prefer to skip more meals during the week and relax at weekends, or visa versa!

Feeding Windows

First break the day down into segments of time called ‘windows.’ For example, 18 hours for fasting (drinking only water or tea and sleeping) with 6 hours for eating. Or you could have any other combination of time spent not eating and time spent eating. Ideally this would be a maximum of 8 hours in which you eat (to get the benefits of fasting). Go for what suits you best, for example if you aren’t hungry until 2pm, open your eating window then.

Fasting On Alternate Days

Either with a set pattern, or by letting your body decide, choose specific days to fast or limit eating time. This method suits active individuals who have exercise or training routines with resting or active days. Alternating eating patterns on specific days can also suit hectic schedules when you don’t want to stop to eat. But, it can also be easy to forget you decided to fast if you don’t have a way to keep track or prompt yourself.

Planned Caloric Restriction

Instead of reducing time, you reduce calories (e.g. by 25%), to get similar effects to fasting. As long as the calories are coming mainly from fat not carbs this method still has huge health benefits. Some people find it easier to reduce food instead of fasting completely and opt for smaller snack-like meals. This method can get you out of a weight loss plateau or be used to have a few extra calories at the weekends.

Fat Fasting

This means cutting calories but increasing your fat intake. Again this will help you get out of a weight loss plateau or recover from a keto cheat. This is not however technically a fast, but it works in a similar way.
You cut calories for a few days while increasing the proportion of calories from fat to about 80 to 90%. This will speed up getting back into ketosis, if you left it, and boost fat burning and metabolism. You can only do this fast once you are keto adapted and your body is used to using fat for fuel. Ensure you still get 1,000-1,200 calories as a minimum and restrict to 3-5 days maximum. Go gentle on exercise during a fat fast and consider supplements to ensure you get enough micronutrition.
These are just a few of the options, you can combine them or invent your own. Find out what works for you. If you do decide to give fasting a go, here are a few precautions:

Start Slow

Give your body time to adapt and don’t push beyond what is comfortable. Fasting should be a gentle physical and mental stretch, not an impossible marathon. Gradually increasing fasting time will give your body time to prepare and adapt.
In fact, if you are new to ketosis, we recommend waiting 3-4 weeks until your body is well adapted before starting intermittent fasting, unless it seems to happen naturally as you have no appetite.

Listen to Your Body

Your mind may have planned to fast but your body may disagree! There are lots of reasons why you may need more calories on a specific day. You could have moved more, slept badly, be fighting off a cold, be emotional or hormonal. Your mind may not know what’s going on, but your body feels it with increased hunger or reduced energy and fasting simply wouldn’t be the best option.
Be flexible with your fasting, but also use gentle discipline to coax yourself through any mental resistance. Simply skipping meals until you feel hungry is one of the easiest methods for both body and mind.

Distract Yourself

Spending time fasting while thinking about food is hard. Find ways to spend your time which will give you something to think about other than food. You will also find fasting much easier fasting in an environment which doesn’t remind you of food. The bonus is that if you fast regularly you can gain lots of extra hours which can be filled with something fun instead, think of all that extra hobby time you can spend doing what you love!

Easy Options

There are so many options, and such huge benefits, it really is worth experimenting with intermittent fasting to see if it could work for you. Many people on the keto diet are surprised by just how easy fasting is.

In comparison, for people eating the standard high-carb diet, fasting is very hard. Eating carbs make insulin and blood sugar go up and down so much it is virtually impossible to curb appetite. Once you are keto adapted you will find fasting comes more naturally and you may even enjoy the freedom it brings. We encourage you to test out how fasting really feels, not how you imagine it might feel, you may be pleasantly surprised.


  • Fasting can be an excellent practice to enhance ketosis and health in general
  • If we constantly eat our bodies do not have the time or resources to perform necessary processes that keep us healthy
  • Fasting gives the body time to heal and reduces the risk of disease
  • There are many different ways you can incorporate fasting into your keto lifestyle

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