There has been a lot of press on the intermittent or alternate day fasting kind of diet which was originally triggered by a BBC2 Horizon TV programme in August 2012. The programme highlighted that by restricting calories on a number of days in a week, people not only lost weight but also reduced both blood glucose and cholesterol.
Normally I would recommend that women eat around 2,000 calories a day and men 2,500 but the important points are the quality of those calories (avoiding sugar and refined carbohydrates) to avoid having blood sugar highs and lows which controls the release of not only insulin but also the stress hormones adrenaline and cortisol. And also to make sure you are eating little and often so again your blood sugar does not drop too low (hypoglycaemia) causing the release of the stress hormones and sending you off for a quick fix. Following these two points help you to lose weight and especially when the fat is around your middle.
So what do I think about intermittent or alternate day fasting? First of all it is not suitable for everyone. If you are pregnant, breast feeding, diabetic, under 18 or have a history of an eating disorder then you shouldn’t follow this regime. Don’t follow this regime if you get blood sugar swings where you feel weak, headachey, dizzy or light headed when you don’t eat. I also don’t think it is good for anyone suffering from chronic fatigue or if you are very stressed. To your body fasting is a stress, because it perceives there is a shortage of food, which is a survival issue, life or death. So if you are already stressed or fatigued you cannot add another stress, lack of food, to your body. Also if you do a lot of exercise or are training for an event then you would need to think carefully about doing this kind of diet.
Also there are many variations to this diet and nobody yet is clear which regime works the best. There is the 5:2 fasting where you fast on two days a week and again it is not clear whether it is better if the two days are consecutive or broken up and also whether it needs to be complete fasting except water or 600 calories for men and 500 calories for women on the fasting days. And if you follow the 5:2 fast with restricted calories, there is no definite research yet to say whether it is better to have all the calories in one meal or spread out throughout the day.
Other regimes suggest alternate day fasting, where you are fasting every other day of the week.
On non-fasting days, no matter what regime you are following the suggestion is that you can eat anything and how much you want.
My recommendation is that if you are going to try this kind of diet then you follow the 5:2 regime and split the two fasting days so that they are not together, so you could fast on a Monday and a Thursday for example. Also I would suggest you do not fast completely but have the 600 calories for men and 500 calories for women.
I think this kind of diet is harder for women than men because we are much more susceptible to blood sugar fluctuations and this can be even harder depending on which part of the menstrual cycle you in. It is especially important that you use some of the calories for breakfast as it is not a good idea, especially for women, to save all the calories for the evening meal otherwise you can feel very tired and moody throughout the day. So on the fasting days have the 500 or 600 calories but you should split the food into regular meals rather than going from breakfast until dinner with no food.
Also it is generally recommended that you drink water during the day but can also load up on black coffee and tea or diet drinks. If you use caffeine to get you through the day then you are going to be living on adrenaline for the fasting days and that is not healthy. You could have hot water and lemon, herbs teas like peppermint or chamomile, grain coffees or some green tea, if you need a bit of caffeine.
And on the non-fasting days, you should still aim to eat healthily and the same amount of calories you would normally eat rather than a trigger to over-indulge.
On the fasting days you could follow this kind of programme:
Breakfast – Two poached eggs and grilled tomato – approx 120 calories
Lunch – Vegetable soup and you could add some tofu for protein – approx. 200 calories
Dinner – grilled salmon with vegetables – approx. 150 calories
But I have to say that you do not need to follow this kind of regime in order to lose weight, especially around your waist, as my Fat around the Middle programme will do that just as well without restricting calories and it also helps lower glucose, cholesterol and helps overcome insulin resistance. And my major concern is that this type of fasting diet could tip some people into having an eating disorder.