Feasting than fasting – it’s the controversial diet that has reached widespread publicity around the world. It’s called The Fast Diet and comes from a new book written by Dr Mike Moseley and Mimi Spencer, a medical journalist and food and fashion writer respectively. The Fast Diet is the creation of Dr Mike Moseley, and it involves just that – fasting.


The Fast Diet is also known as the 5:2 diet. It is based on a principle known as intermittent fasting, where you eat normally at certain times and then fast during other times. The Fast Diet involves five days of normal eating, and two days of fasting. On the two fasting days, you're still allowed to eat but not much. You're allowed just 25 per cent of a normal adult's daily intake. This translates to 500 calories for women and 600 calories for men. On these fasting days you can either consume all your calories in one hit or spread them out in small meals throughout the day. However protein and lots of fruits and vegetables are recommended.


To give you a bit of an idea about how far those 500 calories could stretch: one medium banana has about 100 calories. One orange also has about 100 calories. There are about 250 calories alone in a cup of plain cooked pasta. Add a bit of sauce and cheese and you’ve probably reached your limit for the day. A potential 600 calorie diet could consist of a slice of ham and two scrambled eggs for breakfast and then some grilled fish and vegetables for your evening meal. And of course nothing but water, black coffee and/or green tea to drink.


So what makes The Fast diet work? According to the authors, the two (non-consecutive) days of fasting per week will result in the metabolism working harder on the days you don’t fast. This is intended to result in weight loss and general better health all round. Claimed significant general health benefits include increased lifespan, improved cognitive function and protection against conditions such as dementia and Alzheimer’s disease, and protection from disease such as cancer and high cholesterol. However, it should be noted that currently there is little peer-reviewed evidence that the diet can bring these benefits.

Little is known about the possible side effects of the diet. Anecdotal reports of effects include difficulties sleeping, bad breath (a known problem with low carbohydrate diets), irritability, anxiety, dehydration, and daytime sleepiness. However, more research would need to be done to confirm these side effects and their severity.


For people in good health intermittent fasting should be no problem. It’s worth noting, however, there are certain groups for whom intermittent fasting is not advised. Type 1 diabetics are included in this list, along with anyone suffering from an eating disorder. It’s also recommended that children and those who are already extremely lean never fast. Pregnant women should eat according to government guidelines and not limit their daily calorie intake. If you are on medication of any description, it is recommended to see your doctor first, as you would before embarking on any weight-loss regime. So if you’re tempted to try it, its sensible to talk to your doctor first to make sure doing so won’t put your health at risk.