Fasting No Better Than Conventional Diets


As people try fasting during January to lose weight, a study has found that intermittent fasting is no better than conventional calorie reducing diets.

However, both will help people to lose weight, the study found.

Intermittent fasting

The 5:2 and 16:8 diets are both forms of intermittent fasting.

The 5:2 diet involves eating whatever you want five days a week, and eating a very low amount of calories for two days. The two fasting days are non-consecutive and involve eating 25% of usual calorie intake. This means 500 calories for women and 600 for men.

The 16:8 diet has become very popular recently. It involves eating normally for eight hours and fasting for 16 hours. Most people choose to organise the 16 hours to include when they are asleep, for example not eating between 6pm and 10am, or 7pm and 11am. During those 16 hours, only tea, coffee and water is allowed.


There have been various reports claiming that these intermittent fasting diets are effective for losing weight, and are easier to follow than some other diets.

A new study has looked at whether fasting is actually any better in terms of losing weight than traditional diets that involve an overall reduction in calories.

Different diet methods

Researchers from the German Cancer Research Center and Heidelberg University Hospital conducted analysis of 150 overweight and obese people. One third of them followed a conventional calorie restriction diet (reducing overall calories by 20%); one third following the 5:2 intermittent fasting diet (which also reduces calorie intake over the week by 20%); and one third didn’t follow a particular diet but were advised to eat a well-balanced diet.

The results showed that over the course of 38 weeks, both the group restricting calories and those on the fasting diet had lost weight and body fat. However, there was very little difference between the two dieting methods.

Discipline matters

The weight loss of those in the fasting group was 5.2%, for those in the calorie counting group it was 4.7%, and for those in the non-diet group it was 1.7%.

The researchers conclude that it is not the method of dieting that matters, but that it is kept to. For some people it may be easier to be disciplined for two days, or 16 hours a day; for others it may be easier to make a change in their total diet.


This article was written by a third party source and does not reflect the views or opinions of Ramsay Health Care unless explicitly stated.

Additional comments on the page from individual Consultants do not necessarily reflect the views or opinions of other Consultants or Ramsay Health Care.

Related stories:

Share this article