Review says intermittent fasting works for weight management, not loss

A review of recent studies has found that strategies such as fasting every other day are not the magic bullet for those wishing to shed kilos.

- By Evelyn Parr

Intermittent fasting is no more effective for weight loss than traditional dieting methods, or even doing nothing at all.

(Photo: Rachel Gorjestani/Unsplash)

Intermittent fasting has become a buzzword in nutrition circles, with many people looking to it as a way to lose weight or improve their health.

But new research from Cochrane, an independent nonprofit network of health researchers and professionals, shows intermittent fasting is no more effective for weight loss than receiving traditional dietary advice, or even doing nothing at all.

In this international review, researchers assessed 22 studies involving 1,995 adults who were classified as overweight (with a body mass index of 25-29.9kg/m²) or obese (with a BMI of 30kg/m² or above) to assess the effectiveness of intermittent fasting for up to 12 months.

The authors found that, when compared with energy-restricted dieting, intermittent fasting doesn't seem to work for people who are overweight or obese and are trying to lose weight. However, they note that intermittent fasting may still be a reasonable option for some people.

To recap, intermittent fasting is a tool for weight management that includes three main strategies:

• Alternate day fasting, where every second day is reduced to low or no energy intake;

• Periodic fasting or the 5:2 diet, where one or two days of the week are spent with low or no energy intake; and

• Time-restricted eating or the 16:8 diet, where daily energy intake is reduced to a shorter window, usually between eight and 10 waking hours.

Previous reviews have found differences between types of intermittent fasting. Alternate day fasting, for example, resulted in more weight loss when compared with time-restricted eating.