by Isabella Dutta
June 30, 2014

The 5:2 diet originated in the UK and spread from there to Europe and to the US. The brainchild of doctor Michael Mosley and food writer Mimi Spencer, the diet calls for occasional fasting throughout the week. For two days a week, you restrict your calorie intake, women to 500 calories, men to 600 calories. On the remaining five days, you eat as you normally would.

The idea behind the diet is that the intermittent fasting - as opposed to the continuous reduced calorie intake of most diets - will discourage the body from going into starvation mode. In “starvation” or “conserve” mode, which is the result of the deprivation typical of most other diets, the body hunkers down as if it is in real distress. Instead of burning more calories, it becomes more efficient and thereby burns less.

In the 5:2 diet, by contrast, the body goes into “recovery” mode. In this mode, the body eliminates many impurities WITHOUT slowing down its metabolic rate. In fact, there is some evidence to suggest that the initial response to a reduction in calories is an increase in metabolic rate. Obviously, the highly reduced calorie intake during the fast days is what spurs the weight loss. Exercise is recommended alongside the diet.

The positives:

There is some evidence that occasional fasting has some real benefits, even without the weight loss. Though tests have not proved this conclusively, there is reason to believe that intermittent fasting may improve insulin sensitivity. Fasting in general can also lead to you being more in touch with hunger cues as well as being more able to respond to them appropriately.

But the big issue at stake here - whether or not intermittent fasting leads to weight loss – is still being debated, as the long-term evidence isn’t as yet available. What seems clear is that this type of dieting seems, for some people, psychologically more possible. Many are attracted by the idea of only having to watch calorie intake on two days of the week, as opposed to day in and day out. There are of course books, manuals, articles, videos etc. helping people cope with their fasting days – what to eat, what to avoid, what works best, what makes things hard.

Many are also encouraged by the thought that fasting is not an entirely new-fangled thing, with many religions advocating occasional abstinence from food. And, in the end, two whole days of drastically reduced calorie intake is a likely precursor to significant weight loss. So anecdotal evidence of quick results has fed the general enthusiasm surrounding the diet.

The negatives:

Fasting - even for just two days out of the seven - isn’t easy for everyone. Some people report feeling irritable and lethargic, unable even to sleep properly and obsessing about food constantly. Exercise –-recommended along with the diet - is nigh on impossible for those who find fasting such an ordeal.

This diet is NOT for those with serious food addictions. The non-fast days, for example, cannot be taken up by an orgy of consumption. Not even the most rigorous fasting can hope to make up for that. Instead, the non-fast days are for fairly normal food consumption, which might be a challenge in itself for those seeking help regarding weight loss.

Nor does this diet offer any nutritional advice vis a vis a well-balanced diet. You could theoretically, in restricting your calorie intake and even in eating what you want without any specific guideline, cut out on valuable minerals and vitamins, doing your body some real harm in the process.

And then the final question - does this even work? And the answer, I am afraid, would still have to be that we don’t really know as yet. Some signs are good, though nothing has been conclusively proved. Psychologically, this seems to be tailor-made for some, while for others, it is nothing short of torture. This seems then a diet that plays on your temperament and psyche. Follow it, if you will and good luck to you, but do be forewarned.