Wetenschap - 30 juni 2015

Believer determines whether Ramadan is (un)healthy

Rob Ramaker

Worldwide more than one billion people vast because of the Ramadan. How does such a dramatic change in eating habits influence your health?

Photo: Rain Rabbit

Over one billion people currently celebrate the Ramadan. They do not eat between sunrise and sunset after which the fasting is interrupted by an often festive meal. The fasting month is a religious duty but such a dramatic change in your eating pattern also influences your health. Wheter it is positive or negative, is something you decide, says Sander Kersten, professor Nutrition, metabolism and genomics. ‘It depends on how much you lash out after sunset.’

How does your body react to fasting?

‘Your body can do without food for quite some time. Around twelve hours, like in the Ramadan, it can take that. In our evolutionary past it happened continuously for prolonged periods that we did not have food. What happens is that your intestines and stomach run low 3 or 4 hours after your breakfast. Then you turn to sugar in your liver and then you rely on your fat storage.’

What impact will that have on your own performance?

‘Fasting can result in lesser concentration or headache. I obviously cannot speak for all people who fast, but all kinds of cycles get confused. Your biological and hormonal system are not only adjusted by the alternation of day and night, but also by the timing of nutrition moments.’

Is it unhealthy to take part in the fasting month?

‘A lot of research has been done to the effects of chronically ill people, like diabetic people. But no one has looked at what it does in the long term with healthy people.

‘I do understand that a lot of people are eating excessively after sunset and therefore do not lose weight during the Ramadan. If you do that every year, you gain more and more weight and overweight is certainly unhealthy. When you use the month to get rid of excess weight, you can achieve the opposite. It just depends on how you behave after sunset.’

People who follow the fashionable paleo-diet, try to emulate the lifestyle of prehistoric people. Some of them fast entire or half days and then suddenly eat a lot of food. Is that a healthy pace?

‘Such a diet especially helps you to eat less. In our world you can always eat everything, where you want and as much as you want. When all of a sudden you start fasting, you eventually eat less. It cannot be otherwise. When you poor a nice prehistoric sauce on such a diet, it becomes attractive to follow it. And that's all fine as long as, and that is the crux, you can sustain over the long term.’