- Ana Belén Ropero Lara and Marta Beltrá García-Calvo
- The Conversation*
We hopefully seek water beyond our planet as the only possibility for life to exist. Yet here on Earth we hardly pay attention to it.
Despite the fact that our lives depend on it, water is the forgotten nutrient in scientific research.
The evidence to determine the recommendations for water intake in relation to its effects on health is scarce. Even some food guides don’t even mention it.
The problem is that long-range studies with a large number of participants are lacking.
Only in this way can it be determined how small degrees of dehydration affect us, which are what really occur on a daily basis in healthy people.
In this article we try to give an overview to understand why it is so important to maintain a good state of hydration and how to do it.
In constant equilibrium
Maintaining the water balance in our body is essential for our survival.
For this reason, we have a very fine system that keeps its levels within a narrow range, despite the great variability in water intake.
When we drink little water, they get going of the mechanisms. One of them is to reduce water loss through urine. The other is the mechanism that triggers thirst.
For these reasons, under physiological conditions the accumulation of fluids cannot be the main reason for excess body weight (overweight or obesity).
If we suspect that we retain fluids, we should go to the doctor.
On the other hand, it turns out very difficult to drink so much water as to have negative effects.
This is so, mainly, because the kidney has a high capacity to eliminate the excess in the urine (0.7-1 liter / hour).
Dehydrated we get sicker
Scientific studies point to a direct association between the degree of hydration and certain diseases. Specifically, dehydration has been associated with urological, gastrointestinal, circulatory and neurological disorders.
However, in many cases the evidence is scarce or inconsistent to draw clear conclusions.
Observational studies link a usually low water consumption with a increased risk of future cardiovascular problems.
In the same way, a low fluid intake is also a risk factor for the formation of kidney stones.
In addition to this, a large study was conducted in 2016 with a representative sample of the US population.
The results showed higher rate of obesity in people who did not have good hydration. In addition, the body mass index was also higher.
On the other hand, studies of various kinds point to a direct interaction between poor water intake and metabolic problems.
Furthermore, the loss of body water during exercise appears to adversely affect physical performance.
The brain is also not unscathed when we ingest less fluid than it should. A review published in 2015 found that, based on the 21 studies analyzed, dehydration is associated with less alert and more fatigued people.
Regarding cognitive ability, studies with a larger number of people are necessary to obtain convincing evidence.
How to maintain good hydration
Studies in Spain and in several Latin American countries show that, in general, the population does not reach the recommended water intake. Therefore, there is a need for greater awareness of the need to drink more water.
The best way is to drink when we are thirsty.
It seems obvious, but many people do not feel thirsty, do not pay attention to it, or may not even recognize it.
That is why it is essential to acquire a good hydration habit from a young age. insist a lot on the elderly.
The various institutions recommend us drink 2-3 liters of water a day. This amount should increase in summer or if we do physical exercise.
You have to drink water, there is no other alternative. It is preferable to do it in small amounts throughout the day. It is the best way to promote water absorption.
Other important sources of this nutrient are foods such as vegetables, vegetables and fruits, because more than 80% are water.
Sugary drinks are not an option due to its high content of free sugars. These are related to poor quality of diet, obesity and risk of contracting non-communicable diseases.
Drinks with sweeteners are not recommended either. The World Health Organization (WHO) and the Pan American Health Organization (PAHO) agree that products with sweeteners are not healthy. They consider that “the habitual consumption of foods of sweet flavor (with or without sugar) promotes the ingestion of foods and sweet drinks, even those that contain sugar”.
The manifest lack of studies that lead to the clear determination of the recommendations for water consumption is true. Admittedly, this raises doubts and the obvious temptations to search the internet.
But, if the experts recognize that evidence is lacking, can we trust the claims or controversies fostered by bottling companies, influencers and opinion leaders of all kinds?
These humble authors declare themselves incompetent to put in check the institutions that, with more or less evidence, contribute their critical and well-founded opinion.
Therefore, let’s make water our most faithful companion this summer. Let’s raise our elbow with the conviction that, although it may not seem like a delicacy for our palate, without water, there is no life.
*This article originally appeared on The Conversation. You can read the original version here.
Ana Belén Ropero Lara is profesora youholder of nutrition and brheumatology Y Director of the BADALI project, Nutrition website in the Bioengineering Institute, Miguel Hernández University. Marta Beltrá García-Calvo is professor of nutrition and food science, Miguel Hernández University
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Eddie is an Australian news reporter with over 9 years in the industry and has published on Forbes and tech crunch.