For some years now, intermittent fasting has been proposed as an option for weight loss. This new method raises several questions: is it a healthy diet, is it effective, what are the benefits of intermittent fasting, and is it suitable for everyone? The concept on which it is based is to stop eating during certain hours of the day or to eat very little on certain days of the week. Its justification is to reduce the daily energy intake and blood insulin levels in order to reduce the synthesis of body fat.
HOW IS INTERMITTENT FASTING DONE?
Within this diet concept there are different types of intermittent fasting:
5:2 intermittent fasting
Intermittent fasting 5:2 consists of a diet where you eat what you want for five days and during two non-consecutive days you consume around 500kcal or 600kcal per day.
Intermittent fasting 16/8
Intermittent fasting 16/8 consists of fasting for 16 hours a day and eating for the remaining eight hours every day of the week. This type of diet can vary and become an intermittent fasting 12/12, 18/6… However, the most popular is 16/8.
WHAT ARE THE BENEFITS OF INTERMITTENT FASTING?
First, it should be clarified that there is a lack of scientific studies that demonstrate the effectiveness of intermittent fasting. Many obtain results with few healthy volunteers and with normal weight or overweight, not obesity, so it is not known if it would be equally effective in these cases. Other studies, which are in favor and show promising results, have been done with rats.
That said, the numbers show that this method of weight loss can be equally or even more effective than the traditional method – a diet with energy control divided into several daily meals – when it comes to losing weight and body fat percentage. In addition, they show a decrease in blood pressure and heart rate, as well as in bone mass, although not significantly.
It is important to understand that improving blood pressure or lowering cholesterol or blood sugar is due to weight loss and reduced energy intake, not to fasting per se. In fact, studies that propose intermittent fasting for weight loss insist that the type of diet must be adequate. For example, the Mediterranean diet. This being so, we would return to the fact that the “lifelong” way of losing weight is still a solid and proven system to lose weight in a healthy way.
IS INTERMITTENT FASTING ADVISABLE FOR EVERYONE?
The answer is NO. Intermittent fasting is NOT recommended for everyone. It is strongly discouraged for people suffering from diabetes, eating disorders such as anorexia nervosa or bulimia, or pregnant or breastfeeding women. In these cases, the health risk is greater than the possible benefit. For the rest of the healthy population it could be an option, but it is always advisable to consult a health professional before considering such a method. It is necessary to be sure that it is suitable for the patient and to do it in a controlled way, without losing physical health or creating an inadequate behavior towards food.
INTERMITTENT FASTING PROS AND CONS
As a summary, we could say that intermittent fasting has pros and cons. On the one hand, it seems that it could be an effective method of weight loss for healthy people who want to lose a small percentage of weight -and I would add that they have failed to lose weight with the traditional method-, provided that they accept and know how to control well the feeling of hunger during the fasting hours. However, it is important to emphasize that not everything goes and that it does not exclude the need to follow a healthy diet for best results. For this reason, it is always advisable to consult a specialist to assess whether it is a good method for that person, to suggest an appropriate way to do it and to carry out controls during the slimming period to avoid adverse effects.
