There has been a lot of talk lately about intermittent fasting as a “new” way to lose weight, improve health, and simplify life. But the truth is that fasting is nothing new; in fact, it has been practiced for thousands of years for spiritual, religious, cultural, and health purposes.


What does it consist of? In intermittent fasting, the periods in which food is not eaten are lengthened, and everything that is going to be eaten during the day is consumed in a certain window of time. There are several types: 12/12 with a 12-hour fast and a 12-hour eating window; 8/16 which involves 16 hours of fasting, and eating two meals in an eight hour head start, is one of the most popular; 24-hour (one meal a day, or OMAD) or 48-hour fasts; the 5/2 plan which means eating normally five days and fasting two days a week.


In this regimen it is not specified so much what you should eat, but when you should eat it. In this sense, we cannot really classify it as a diet but rather as an eating pattern. It must be said that hydration is even more important when you fast, and that water does not break your fast, so drink at least eight glasses of water during the day.


  • It seems to be very effective for weight loss and body fat, since eating only once or maximum twice a day tends to reduce calorie intake. A study published in the scientific journal Nutrition and Healthy Aging found an average weight loss of three kilograms in 12 weeks, and an average reduction of 341 calories in the amount of calories eaten.
  • It has also been found to have positive health effects such as lowering cholesterol, improving insulin sensitivity, and reducing inflammation.
  • It seems to increase energy and cognitive functioning.
  • It is a regimen that instead of complicating your life simplifies it, since it reduces the time, effort and money that you must invest in food, and you can apply it anywhere.


  • It can cause some side effects such as dizziness, headaches, irritability, or low concentration.
  • The most vulnerable groups such as children, the elderly, pregnant or lactating women, people who are underweight or with eating disorders or chronic diseases should not fast without close supervision by a doctor.
  • It can be a very radical regimen and difficult to sustain for some people who are used to eating three or more meals a day.
February 20, 2023 — Laura Posada