While the idea that you can eat anything on your free days sounds great — especially for dieters who struggle to stick to low-calorie eating plans long-term without falling off the wagon — many nutritionists believe that those on the alternate day diet could end up over-indulging on ‘feast’ days, and actually put on weight.
However Dr Krista Varady of the University of Illinois in Chicago, one of the scientists involved in research into intermittent fasting, insists that this doesn’t happen.
‘Our studies show that people end up losing weight because they can’t fully make up for the lack of food on the fast day on the feed day. And people in our studies didn’t binge. They only ate about 100 per cent to 110 per cent of their calorie needs.’
Her findings fit in with what Adriana Wheatley discovered.
‘I think because, unlike other diets where certain foods are restricted, you know that you can have whatever you want, you’re just a bit more relaxed about things. I don’t go crazy on my feed days, but I might opt for a sandwich rather than having a salad, and have pasta, which in the past I might have avoided if I was trying to lose weight, but I don’t go over the top,’ she says.
Opinion is divided on just exactly what a fast entails — some say you should eat nothing at all for anything from 17 to 24 hours, while others argue that you can have 500 calories, but they should all be consumed in a single midday meal.
Michael Mosley on the Horizon programme ate his 500 calories split over two meals, breakfast (ham and eggs) and dinner (steamed fish and vegetables), as he found that was the best way to avoid feeling hungry or deprived.
Nutritionists do agree that it is vital to eat nutrient-rich foods if you only eat 500 calories a day.