The experts in Nutrition and Dietetics of Centro Salud 10, Carla Gonzalo and Ángela Martín, talk about fasting, a new form of abstinence from food for a determined period of time. They comment that the most popular is the 16/8 fast, in which one must fast for 16 hours and can eat for the remaining 8 hours. Although there are also other types of fasting, such as 12/12 or 20/4 fasting, the latter being the strictest, where food can only be eaten for 4 hours a day.
How can fasting affect our health?
The beneficial effects of intermittent fasting are currently being studied, among which are the improvement of the lipid profile, thanks to the reduction of blood triglycerides, the improvement of insulin sensitivity, the reduction of blood glucose levels, the reduction of inflammation markers, the activation of autophagy (related to cell regeneration), the increase of metabolism and the reduction of body fat.
Taking into account the beneficial effects, intermittent fasting can be a useful strategy to use in metabolic pathologies such as type 2 diabetes, dyslipidemia, hypertension, overweight and obesity, being aware that the positive effects occur gradually and knowing that increasing the hours of fasting does not increase the benefits.
Therefore, intermittent fasting is a resource that can be beneficial for certain pathologies, as well as to learn to differentiate real hunger from emotional hunger, but it is not a miraculous method or suitable for the entire population. For this reason it is important to be guided by the advice of a professional, such as a dietitian-nutritionist.
There are several situations in which intermittent fasting is not recommended: when there are increased caloric requirements, such as in the case of high-performance athletes, pregnant women or people who find it difficult to increase muscle mass; in situations of stress, and in the context of an eating disorder, since there is a risk of abusing fasting as compensation.
For how long is fasting recommended?
There is no specific recommendation when it comes to intermittent fasting, so the advice of a dietitian-nutritionist is advised to assess the case of each individual.
Sometimes it is recommended to do it one or two days a week, while other people prefer to do it at specific times when they eat more food (events, Christmas, etc.) to let the digestive system rest after a larger intake.
It is important to remember that fasting does not compensate for a poor diet. Good eating habits are necessary to obtain the benefits provided by this resource.
For those who have never fasted before, it is recommended to start with a shorter fast, such as the 12/12 fast.
Does fasting have a rebound effect?
It should be noted that fasting 16/8 does not mean skipping a meal and saving those calories. The daily caloric requirement when doing intermittent fasting should be covered, the only thing that changes is the distribution of those calories throughout the day, concentrating in fewer hours. Therefore, if carried out correctly and supervised by a professional, there is no rebound effect.
However, a badly planned intermittent fasting or taken to the extreme with a great caloric restriction can be more harmful than beneficial, and in this case it could have a rebound effect when returning to the usual diet.
How can we combine fasting with day to day life?
In the case of fasting 16/8 the most common way to follow it is to skip breakfast, so that it would not influence lunch or dinner. In this way one could have dinner at 21h, avoid breakfast the next day and eat at 13h, so that there would be 16 hours of fasting that would not interfere in the social life of that person.
In the case of wanting to eat breakfast, another option would be to have the first meal of the day at 8 am, eat around 12 pm and have the last main meal of the day at 4 pm, in order to fast until 8 am the next day. Therefore, fasting can be adapted to the time of day preferred by the person who does it, without becoming a problem.