The Science Behind Six Popular Diet Fads, From Keto And Paleo To Low GI And 5:2
It seemed like a magic solution when the idea was first popularised by Dr Michael Mosley: “fast” for two days in the week, consuming between 500 calories (women) and 600 calories (men), and then eat a healthy, balanced diet for the remaining five days.
The Science Behind Six Popular Diet Fads, From Keto And Paleo To Low GI And 5:2
Since then, the term intermittent fasting has been used to describe any window where you don’t eat; typically, eight hours.
The Science Behind Six Popular Diet Fads, From Keto And Paleo To Low GI And 5:2
“The idea is that fasting creates a calorie deficit, which means that once the body uses up its carbohydrates stored in the liver and muscles, it relies on fat stores for energy instead, which can lead to weight loss,” says Sarah Coe, nutrition scientist at the British Nutrition Foundation.
The Science Behind Six Popular Diet Fads, From Keto And Paleo To Low GI And 5:2
“There is some evidence from clinical trials to suggest that intermittent fasting can help with weight loss. But the evidence for the 5:2 diet specifically is limited compared to other weight-loss diets.”
The Science Behind Six Popular Diet Fads, From Keto And Paleo To Low GI And 5:2
Importantly, evidence from clinical trials also suggests that forms of intermittent fasting such as the 5:2 diet don’t appear to be any more effective than more traditional weight-loss diets with continual daily calorie restriction.
The Science Behind Six Popular Diet Fads, From Keto And Paleo To Low GI And 5:2
“There is also some evidence to suggest that intermittent fasting could bring other health benefits, including improved blood pressure and blood-glucose control, and lower cholesterol levels, which could reduce the risk of disease. But compared to other types of weight-loss diets, the amount of evidence for any specific health benefits of intermittent fasting is limited,” says Coe.
The Science Behind Six Popular Diet Fads, From Keto And Paleo To Low GI And 5:2
Many of the studies are short term or in small numbers of subjects, or have been done in animals, so more research is needed to explore the possible long-term health benefits in humans.
Downsides
The 5:2 diet can be restrictive, and some people may find it challenging to stick to in the long term, particularly as it can result in hunger and low energy levels, disrupting work or social plans.
For the 5:2 diet to work, it’s important to stick to the calorie limits on “fast” days and not go overboard on the “normal” days, as this can hinder any weight loss or could even lead to weight gain.
The 5:2 diet isn’t recommended…