Intermittent fasting – is it worth the hype?

You have probably read a magazine article or watched a Netflix show about the benefits of intermittent fasting. However, is intermittent fasting a realistic and sustainable weight loss method compared to a traditional kilojoule deficit diet?


What is intermittent fasting?

Intermittent fasting is a way to reduce your kilojoule or calorie intake to support weight loss. It is a cycle between fasting (only eating between 2,000 and 2,500 kilojoules per day) and eating regular meals on other days. People may also “severe fast” and not eat at all on their fasting days.


Why do people try intermittent fasting?

Over the last five years, intermittent fasting has generally become a more acceptable way to lose weight in our community, perhaps due to the media and celebrity views. There is also a notion that intermittent fasting is an easier way to lose weight compared to traditional weight loss methods.


The types of intermittent fasting

There are two common variations of intermittent fasting


5:2 diet - eating regularly for five days of the week and heavily reducing foods intake on two days of the week


Alternate fasting – alternate days between fasting and regular eating every week


The latest science

There are only a handful of robust and recent studies available comparing the effects of weight loss through intermittent fasting and a traditional kilojoule deficit diet.


In short: all studies observed no difference in the amount of weight loss between the two groups (intermittent fasting or traditional kilojoule deficit diet)


In the study researching 1) 5:2 diet with fasting on different days and 2) traditional weight loss, both groups lost between 8 – 9kg at the end of the study period.


The study was repeated with 1) 5:2 diet with fasting on consecutive days and 2) traditional weight loss. Both groups lost between 6 kg at the end of the study period. However, a reduction in insulin resistance (glucose moving into cells) was greater in the 5:2 diet group compared with the traditional weight loss group.


In terms of weight loss, both groups and both study protocols reached the same amount of weight loss. This highlights that there are many different ways to lose weight successfully in the short term. It’s important to consider that there was no long- term follow up so we do not know if the participants regained or maintained their weight loss.


My nourish tip

The science has confirmed that there are many different ways to lose weight. However, I am only interested in helping people lose weight through an easy, realistic and sustainable way which is tailored to the individual’s preference including their medical and social history.


If this sounds like what you are looking for in a dietitian, make an appointment with me


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