Water

Water and body balance

Water is part of the environment in which cells function and circulates with the blood. It participates in particular in the transport of substances and the elimination of waste. The body continually loses water, among other things through urine, respiration and perspiration; drinks and food help to replace these losses. Needs therefore evolve with what comes in and what goes out.

The kidneys filter the blood and then reabsorb a large part of the water and useful substances. The rest forms urine. This work maintains the balance between water and minerals, including sodium, necessary for the functioning of nerves and muscles. Drinking serves to support this balance; adding lots of water does not indefinitely increase the body's ability to function.

Sweating and performance

During exercise, perspiration allows heat to escape when sweat evaporates. Significant water loss can increase stress on the body and degrade performance. The ACSM recommends an individualized strategy, as losses vary greatly depending on the person and conditions. The expected benefit is above all to limit the degradation linked to lack of water, rather than gaining additional capacity by drinking more.

Sweat also carries sodium. Conversely, drinking excessively during exercise can dilute the sodium in the blood and cause hyponatremia, sometimes serious. This explains why sports advice takes into account both water, losses and, depending on the situation, electrolytes. Neither intentionally restricting water nor drinking without limit is a good strategy for improving your appearance or performance.

What water can change for the skin

A systematic review published in 2018 notes a slight increase in skin hydration after additional water intake, especially in people who consumed little before. The authors, however, emphasize the small number of studies and their methodological limitations. The result allows us to envisage a modest benefit when intakes are low, without promising a visible change in anyone already sufficiently hydrated.

Drinking water and moisturizer act at different levels. The treatment directly helps the surface of the skin to retain water; drinking supports the general balance of the body. Dry skin may therefore need appropriate care even when you drink enough. Increasing liters does not replace skin hydration, and the data does not justify presenting water as a treatment for wrinkles or acne.

Appearance and indirect benefits

Drinking a lot is not a reliable method to deflate the face. Tissue volume depends on several factors and the body already regulates water and minerals. Dehydrating yourself on purpose to appear drier compromises this balance. If swelling becomes unusual or persistent, finding the cause is more useful than trying to correct it by significantly changing the quantities drunk.

Water also has a very concrete benefit when it replaces a sugary drink: it does not provide calories and avoids those of the replaced drink. This benefit depends on the actual replacement, not on any particular fat-burning power of water. For appearance, the right place for this routine therefore remains that of a daily basis, with effects mainly linked to the prevention of withdrawal and the choice of drinks.