Do you know what intermittent fasting is? Do you know its benefits and possible risks? A scientific review has recently come to light that highlights some very interesting results from intermittent fasting.
In this article, we will see in detail what this habit is at a practical and nutritional level, its possible benefits, the scientific basis, and how to do it to avoid entering a situation of health risk.
What is this health practice?
There are several formulas for intermittent or sporadic fasting, Like the daily periodicity (the best known), which consists of at least 12 hours of fasting, the best known being the “16/8” model: 16 hours of fasting and 8 hours of feeding. There is also the weekly: generally one or two days per week of fasting, consecutive or not, and finally the monthly: fasting two days in a row each month.
In terms of the schedule, the most common practice is to eat from 10 a.m. to 6 p.m. (taking into account the intermittent fasting of the daily frequency). In the fasting period, 8 hours of sleep are considered.
Foods and Calories in Intermittent Fasting
Regarding calorie intake, it is considered that with the fasting period, the usual general intake of kilocalories decreases between 300 and 500 per day (approximately and depending on the age, sex and physiological conditions of the person).
Regarding the products to be consumed, these must always be fresh, nutritionally balanced and healthy foods especially vegetables and fruits. Preferably homemade and seasonal foods.
The basis of the diet when you are not fasting are vegetables and fruits, but always taking into account legumes, seeds, nuts, whole foods (with labels that endorse them), as well as foods of animal origin. (for people other than vegans) such as eggs, dairy products, fish, seafood and meat.
Benefits of intermittent fasting
Numerous scientifically rigorous studies have led to the conclusion that, in summary, eating within 6 hours and fasting for 18 hours can trigger a specific metabolic pattern change; in other words that is to say, switch from a metabolism of obtaining energy from glucose (in the liver) to a metabolism from ketones and fatty acids (In adipose tissue, i.e. fat).
This change in metabolism would lead to a series of changes at the cellular level, which would involve increased resistance to stress, increased longevity, as well as a decrease in the incidence of certain diseases, Such as cardiovascular disease, obesity, diabetes and cancer, among others.
This series of articles demonstrates the benefits of intermittent fasting, showing that it’s not just about weight loss and reduction of free radicals (which oxidize and damage our cells), but go further.
Among the benefits of intermittent fasting, we find fat loss while maintaining muscle mass, Improving spatial, verbal and associative memory, as well as improving overall cognition (mental processes).
Physiological processes involved
On the other hand, intermittent fasting triggers adaptive cellular responses that integrate between organs. Thus, the regulation of glucose is improved, resistance to stress is increased, and inflammation in cells is also suppressed.
During the fast, cells activate pathways that improve intrinsic defenses against oxidative and metabolic stress and those which eliminate or repair damaged molecules.
When recovering from fasting (eating and sleeping), cells increase protein synthesis, experience growth and repair. Maintaining an intermittent fasting regimen, especially when combined with regular exercise, works many long-term adaptations that improve overall mental and physical health.
Risks to consider
While we have known some of the benefits of intermittent fasting, we need to be careful. Specialists from SEEN (Spanish Society of Endocrinology and Nutrition) point out that, despite the possible benefits of intermittent fasting, this it cannot be considered a diet.
This is because this practice refers to the restriction of food for a certain period of time, while the concept of diet refers to a common practice on the consumption and restriction of food and drink.
In addition, experts point out that in some vulnerable people, he could develop an eating disorder by this habit, if it is not carried out in a controlled and studied manner.
Importance of healthy lifestyles
To have a healthy life and maintain a normal weight (ideal weight according to our height and our physical characteristics), despite taking into account the benefits of intermittent fasting, it is essential not to forget to practice and to have some habits. sure education around food and nutrition.
Some basic tips for a nutritionally healthy lifestyle would be: always plan menus, eat five meals a day, do not snack between hours, control the amounts of food, eat a balanced diet and all food groups, eat slowly and limit sweets and processed products in general. Obviously, without forgetting the recommended amounts, and without forgetting the exercise.
Intermittent fasting under medical supervision
As we have seen, scientific studies have shown the benefits of intermittent fasting in relation to many health problems, such as obesity, diabetes mellitus, cardiovascular disease, cancer, and neurological disorders.
At the level of animal experiments (rodents and primates), it has been shown that intermittent fasting improves health throughout life, while at the clinical level (people), studies have only been carried out on short periods (months), so much research remains to be done.
So, the benefits of intermittent fasting have a scientific basis. Anyway, it is a delicate practice which must always be practiced under medical supervision.
It should always be borne in mind that intermittent fasting should be carried out for the short term and that it is not recommended for everyone, since each person has their physiological needs and, of course, should not be excessive.
- Mahan L, Kathlee, Janice L, Raymond (2017). Krause. Diet therapy. Elsevier Editorial. 14th edition.
- Mark P. Mattson, Valter D. Longo and Michelle Harvie (2016). Impact of intermittent fasting on health and disease processes. Reviews of Research on Aging (Rev. Res. Aging).
- Rafael de Cabo, Ph.D., and Mark P. Mattson, Ph.D. 2019. Effects of intermittent fasting on health, aging and disease. The New Journal of Medicine (NEJM).
- Stephen Anton, Stephen, Leeuwenburgh, Christiaan (2013). Fasting or calorie restriction for healthy aging. Experimental gerontology (Exp Gerontol).