Do you have questions about nutrition? Send them to us at comer@lavanguardia.es, our nutritionist Aitor Sánchez will solve all your doubts.
I would like to know if fasting really helps to lose weight and what are the best times to do it (Sandra Sánchez, reader)
Hello Sandra,
Fasting understood as a technique in which we stop eating food is obviously related to weight loss because it implies a reduction in our caloric intake. But of course that does not mean that they are neither the best technique nor the ideal approach to address weight loss.
We must distinguish between two main types of fasting: intermittent and prolonged.
Prolonged fasting results in longer periods of time and usually occurs involuntarily. On the other hand, intermittent fasting is a dietary technique that has become very fashionable recently and which consists of spending longer time windows to eat food throughout the day, for example 2 or 4 p.m. Although multiple health benefits are being attributed to intermittent fasting, most of them are related to the weight loss that it promotes, and it is simply one more way to achieve a caloric deficit throughout the day. If anyone decides to do intermittent fasting, they should be clear about this.
Regarding schedules, some are not significantly better than others from a physiological point of view, but the option of skipping breakfast and mid-morning is the one that is socially more accepted and more bearable.
We cannot help but remember that if you are looking for a way to achieve a healthy weight, the best way is to follow a healthy diet and an active life, the convenience or not of using intermittent fasting is quite secondary within all these priorities.
Hello. I eat very little fish, and they always tell me I'm doing wrong, because it's very good. Sometimes I also have a hard time knowing which one to buy and which types are in season. Another thing that scares me is that they have metals or plastics. Which fish should you reduce your consumption due to their heavy metal and plastic content? Which do not have this risk? (Gemma Garcia, reader)
Fish is a healthy protein source, after legumes it is the second that gives us the best health results. Although it is also true that due to the state of the seas and the bad practices carried out in some fishing fleets, the fish that are marketed for human consumption are increasingly contaminated: both by heavy metals and by dioxins, all derived from the environmental pollution.
However, to date, all the data suggests that the benefits of consuming fish compared to other protein sources outweigh the possible damage caused by environmental pollutants.
Those fish that are most contaminated by these elements tend to be large oily fish, since the bioaccumulation phenomenon occurs in them in greater volume. Being large fish, they have spent more years of their lives eating other living beings in the sea, and being blue, all these environmental pollutants accumulate in their bodies since they tend to be liposoluble (they are stored in fat).
For this same reason, in the recommendations for vulnerable populations such as pregnant women or children, it is recommended to limit the consumption of these fish: tuna, swordfish, pike and different sharks.
In the event that you want to look for fish that is in season, clarify that this tends to affect especially that fishing has a lower environmental impact but does not have a great difference in terms of health. You can find different seasonal fishing calendars on the Internet to delve into it.
