The cocktail that seems to refresh you may be asking for just the opposite: to make room for a glass of water. Photo: Nadin Sh / Pexels
Too much ice, but little hydration…
A cold beer or a summer red wine with soda seems the best antidote against the heat. The problem is that alcohol can give you more thirst than a bag of chips
By Paka Díaz
August 22, 2026 / 08:00
In summer we tend to think that a very cold beer or a tinto with soda, with its good slice of lemon and lots of ice, refreshes and hydrates. Even, for the boldest, some cocktail with a tropical name. Alcohol is never a good choice but in combination with high temperatures it is even worse.
“Although a beer or a glass may contain water, alcohol has a diuretic effect,” explains Laura Salud, pharmacist, nutritionist and CEO of Salmo Labs. What happens when you drink drinks is that alcohol “favors the elimination of fluids through urine. In other words, the body ends up losing more water than it seems to be receiving,” the expert clarifies. In addition, she emphasizes: “When it’s hot, we are already losing fluids through sweat, so alcohol consumption can increase even more the risk of dehydration.”
When the heat tightens, beware of what you drink
Alcohol-induced dehydration occurs in all seasons of the year, whether it’s hot, cold or stormy. But it worsens when heat comes into play. In summer we already lose fluids constantly through sweating. But if we add alcohol to that, the body’s water balance begins to falter. And it’s not just about water. The key lies in the composition of sweat, rich in minerals that the body needs for its hydration homeostasis. “When heat and alcohol combine, the body loses water and also essential minerals, such as sodium or potassium,” notes Salud.
This drop in electrolytes, those minerals that help your muscles contract and relax properly, and regulate hydration, has consequences. “Depending on the level of dehydration, it can affect the normal functioning of muscles, nerves and the cardiovascular system.”
The consequences do not wait. Symptoms can appear such as dizziness, headache, a feeling of weakness or reduced tolerance to physical effort. The nutritionist focuses on that very Spanish habit of having a few beers and then playing a game or volleyball on the beach. “If we drink, it is very important to avoid making large physical efforts or training intensely. Especially on very hot days or during the hottest hours of the day, because the high temperatures will make us sweat more and dehydration will be even more pronounced.”
But if I’m not thirsty
The dehydration caused by alcohol consumption during summer vacations can trigger multiple side effects. As exhilarating as a few beers at the beach bar may seem, it is very likely that fatigue and even a slight irritability will appear, which can trigger summer disputes that would not occur at other times. In addition, although alcohol may initially create a sensation of drowsiness, it worsens sleep quality and favors nocturnal awakenings. It should be noted that sleeping well is one of the great casualties of this equation.
Another problem is that people are not usually aware of what is happening, since the feeling of thirst decreases, explains the nutritionist. This lack of alerts makes us not drink the water our body needs. The expert recalls that dehydration and heat strokes tend to make thirst go unnoticed until the body’s water shortage starts producing severe effects. “Not to mention that, when consuming alcohol, body composition changes and the organism has less capacity to adapt to temperature changes and to fluid loss.” In other words, dehydration is harder to cope with.
These risk factors worsen as we get older. “With the years, they tend to become more evident. And what is worse, the sense of thirst is lost, which further increases the risk,” confirms the expert.
The only proper ways to stay properly hydrated
To reconcile pleasure, heat and proper hydration, the expert offers a key to always follow: “The best strategy is not to wait until you are thirsty to drink.” But she notes that the important thing is to consume water regularly throughout the day and increase intake when it is very hot or physical activity is performed. And, if alcohol is consumed, her recommendation is to “alternate it with water to minimize fluid loss.”
It also helps to improve hydration to increase in daily life the consumption of “water-rich foods, such as fruits and vegetables,” the expert notes. That said, if what you want is to stay hydrated in the face of high temperatures, her advice is that the main beverages you drink throughout the day should be water, sparkling water, cold infusions or drinks made with natural fruit. But all, of course, “without added sugars,” the expert emphasizes.
