Today we want to give you a more in-depth overview of Intermittent fasting. What it even is, and how the various types of intermittent fasting could potentially benefit you should you wish to give this approach a go.


Intermittent fasting is essentially a dieting method for the purpose of weight loss/fat loss which involves extended periods of ‘fasting’ periods, interspersed with ‘feeding’ periods. The average negative energy deficit (Calorie deficit) over the various periods results in weight loss.


Intermittent fasting can basically be broken down into three different classes:

1) ALTERNATE-DAY fasting.

2) WHOLE-DAY fasting. 

3) and TIME-RESTRICTED fasting.

There could debatably be other fasting types which fall outside of these umbrella terms for intermittent fasting, but it’s generally accepted that the vast majority of strategies will fall within these classes.


ALTERNATE-DAY fasting normally consists of a full 24-hour period of fasting, followed by a 24-hour ‘feeding’ period. So essentially a day of complete fasting, and a full day of eating normally. The calorie deficit created on the fasting days are not compensated for fully on the feeding days, and as a result the weight loss technically occurs on the fasting days.

WHOLE-DAY fasting generally involves one or two 24-hour fasting periods over the period of a week in order to create the energy deficit over 7 days on average. An example of this approach would be the ‘5:2 diet’ whereby 5 days are eating normally at ‘maintenance’ calories, whilst including 2 days over the week fully fasting. Not all ‘whole-day’ fasting strategies involve a zero-calorie intake approach on the fasting days, but rather dramatically reduced food intakes on those days.

TIME-RESTRICTED fasting strategies typically have a fasting period incorporated into every day of the week. Normally the fasting periods are 16-20 hours in total, and the feeding periods are 4-8 hours per day in length. So your approach may be a 16/8 fasting approach, or a 20/4 fasting approach per day for example. 

We hope everything makes sense so far.

To keep this topic as simple and easily digestible as possible (Sorry about the TERRIBLE nutri-pun!) Below is the 2nd instalment of the intermittent fasting series, so read over this again before moving onto the next part.We do not want to overwhelm you with info!



Here is the follow-up from the above, about Intermittent Fasting and all the different variations. If you haven’t understood the first part, please take another look, as this post will make way more sense that way around.

As we have already summarised previously we have 3x main umbrella terms for intermittent fasting: ALTERNATE DAY fasting, WHOLE DAY fasting, and TIME RESTRICTED fasting.

In this post we will be sharing a little more about the physiological effects that the various strategies have, and how effective they can be.

Let’s jump in…


One of the main potential disadvantages seen within intermittent fasting strategies is the loss of LEAN MUSCLE tissue as WELL as FAT mass. Ideally; for the purpose of the maintenance of quality levels of body composition, we need to prioritise the loss of FAT mass from the body, whilst simultaneously PRESERVING lean muscle tissue to as much of an extent possible.

Another more obvious limitation is one’s ability to sustain an intermittent fasting approach long-term to reach weight management goals. Intermittent fasting can be very difficult to fit in and around daily lives. Let’s say you have an important presentation at work and this so happens to fall on a day where your calorie intakes are zero- how are you going to feel? Could this hinder your performance mentally? If you’re hitting the gym or working out on regular days throughout the week, this is also likely to leave you super low on energy during sessions too.


Generally the more severe the calorie deficit created via intermittent fasting, the more severe the loss in lean muscle tissue as part of the weight loss process. This can be limited via the intake of quality protein intakes and adequate amounts of protein intakes on average over the week, supplemented with resistance training throughout the week too however!


A study by Harvie and colleagues compared the daily energy restriction approach (dieting which involves a daily calorie deficit, like calorie counting, or low carb diets for example), to whole day intermittent fasting, and in this study actually suggested a significant benefit to fat loss over a 3month period when using intermittent fasting!

We know Other studies have displayed that there can also be results sustained over longer periods of a year too, so depending on how well this approach fits for the individual, you could also see long-term benefits to intermittent fasting too.


A less obvious example of intermittent fasting occurs all the time during Ramadan, a really well researched section of intermittent fasting due to the amount of people who regularly take part in this protocol across the world. In a nutshell Ramadan fasting involves the restriction of both food and drink during sunrise to sunset, normally for religious purposes.

It’s not surprising that as a result significant levels of weight loss can take place, but also involves a loss from both lean muscle mass and body fat also.


– Intermittent fasting can be a very successful weight loss method due to the simplicity of following these strategies.

– Normally you are likely to see loss in fat mass and lean muscle mass too, unless you focus as a priority on limiting muscle mass loss by prioritising the correct protein amounts and quality over the week on average, combined with a well-structured resistance training program.

– Intermittent fasting can potentially reduce body weight & appetite at the same time.

– From the research intermittent fasting protocols appear to be just as effective as continuous daily energy restrictive strategies (Like normal dieting/daily calorie counting etc.)

– Intermittent fasting involves careful planning in order maintain suitable levels of day to day health and safety, whilst ensuring that it’s as effective as possible too!

We really hope that this 2-part series has shed a large light on the complicated area of intermittent fasting. Hopefully it has given you some clarity on the different types of approaches, and how effective they can be!


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