Scientists say intermittent fasting is the key to future weight loss regimes

THE secret to losing weight and lowering your risk of cancer, heart disease and Alzheimer's is to starve yourself every other day, according to scientists.

Fat loss pills and strenuous exercise could be a thing of the past, with a new diet claiming to improve your waistline as well as extend your life and keep wrinkles at bay.

The 5:2 diet - also known as intermittent fasting - requires two non-consecutive days of "fasting" each week, when the dieter is to consume no more than 500 calories if they are a woman and 600 if they are a man.

There are no dietary restrictions for the remaining five days, which are often referred to as the "feeding" days.

The diet has gone viral following the BBC documentary Eat, Fast and Live Longer by doctor and journalist Michael Mosley, which screened in the UK last year.

It is expected to create a similar craze when it screens in Australia on SBS on April 22.

The program follows Dr Mosley on an intermittent fasting investigation.

In six weeks following the diet, he lost over 6kg and 25 per cent of his body fat.

His cholesterol dropped and his blood glucose, which he described as "borderline diabetic", went back to normal.

Dr Mosley also found that fasting lowered levels of IGF-1 in the body - an insulin-growth hormone - which in turn lowered blood pressure and the risks of cardiovascular disease, cancer and diabetes.

There are now 5:2 groups on YouTube, Facebook and Twitter, as well as blogs dedicated to the diet.

Sue Hollis said she discovered fasting through her Raw Fit trainer Ricardo Riskalla - and dropped 8kg almost instantly.

"I tried Atkins, the lemon detox, you name it, I've given it a shot in the past," she said.

"But I could never shake those last few kilos.

"For me, fasting worked instantly. I felt better, lost weight and I even became stronger and faster."

And while the concept of not eating sounds strange to a lot of people, Ms Hollis said it actually makes a lot of sense.

"It's all about your body resting and functioning without the added implication of digesting food all the time.

"It took a couple of weeks to get used to it because I was doing a lot of hard training, but it actually works and I've seen such an improvement."

A typical breakfast on a fasting day might be two eggs and a small portion of smoked salmon and another meal of grilled chicken and steamed vegetables.

But Fitness First Sylvania trainer Chris Hujber described the method as another fad diet that was potentially "dangerous" to the body.

"These diets give the quick fix, not the lifelong answer.

"Reducing your calories by this much, even every second day, will put your body in starvation mode.

"Getting rid of any food group is dangerous. Balanced meals of healthy carbs, fats and proteins is the only way to look lean and stay lean for life," said Mr Hujber.