Intermittent Fasting - Will you actually lose weight?

I’m going to call it. Intermittent Fasting is/was the top diet trend of 2019. Keto was all the rage 2018, but now everyone’s on the Intermittent Fasting bandwagon. Should you be jumping on it too?  

What is Intermittent Fasting? 

Fasting is defined as the choice to completely abstain or reduce your food and/or fluid consumption for a set period. Intermittent Fasting is quite simply an eating pattern that cycles between periods of eating and not eating. This way of eating doesn’t specify foods you should and shouldn’t eat, but rather dictates when you should it. Intermittent Fasting is a change of eating patterns, rather than a diet. 

Types of Intermittent Fasting

-       Time Restricted Eating

Also known as the 16:8, this involves restricting your meals to an 8-hour window each day and fasting for the remaining 16 hours. Following this pattern, you might choose to skip breakfast and have an early dinner or start eating earlier in the day and start fasting from 4pm or so. For example, you might choose to skip breakfast, and eat between 12-8pm, or have a later breakfast at 10am, and have dinner by 6pm.

-       Alternate Day Fasting 

This form of fasting involves cycling one day of fasting and one day of your regular intake. On the ‘fasting’ days, it is recommended you consume less than 25% of your recommended daily energy intake, roughly 400 calories. 

-       5:2 Method 

One of the most popular intermittent fasting diets, 5:2 involves reducing caloric intake for two ‘fasting’ days each week, roughly 500 calories for women and 600 calories for men, per day.The other five days then allow for relatively unrestricted, ‘healthy’ eating. 

What happens to the body? 

Generally speaking, you are likely to lose weight when undertaking any of the above forms of Intermittent Fasting. But let me explain… The reason people who fast intermittently will usually experience weight loss is because they are eating less kilojoules than they were eating before – not necessarily because of the ‘fasting’. In fact, this is why most ‘diets’ (regardless of restrictions put in place) will cause weight loss – because the total amount you are eating is less than what you were before. Interestingly, there are some studies which favour Intermittent Fasting to result in less muscle loss, when compared to a general calorie deficit diet, helping you maintain lean muscle mass.

Depending on how tightly you comply with these fasting methods, there’s potential for numerous other benefits, outside of the weight loss. Research suggests that any prolonged period with little to no calories for short periods has been linked to lowered cholesterol levels, improved blood pressure and blood glucose control.

The verdict? 

At the end of the day, while Intermittent Fasting may cause short-term weight loss, it’s unlikely to be sustainable for an extended period of time. I wouldn’t suggest long term fasting anyway, as it places you at increased risk of slowed metabolism and energy conservation. But in the short term, fasting holds great potential for both weight loss and improved general health. As with any diet, it’s best to get the all clear from a trusted medical professional before commencing.