Heatwave: why drinking water alone isn’t always enough?

During periods of intense heat, the body activates its main defense against overheating: sweating. This natural mechanism helps regulate body temperature, but it carries away much more than just water.

During a heatwave, the body can lose between 0.5 and 1.5 liters of sweat per hour. Sweat is not only water; it also contains essential minerals, known as electrolytes, which the body cannot produce on its own.

The Key Role of Electrolytes¹˒³

The main electrolytes lost through sweating are:

1. Sodium – helps regulate fluid balance within cells and maintain blood pressure. It is the electrolyte lost in the greatest quantity through perspiration.
2. Potassium – essential for muscle contraction and proper heart function.
3. Magnesium – involved in nerve transmission and energy production.
4. Chloride – contributes to maintaining the body’s acid-base balance.

When these losses are not adequately compensated for, drinking water alone may not be enough to restore the body’s balance. This is why someone may still feel tired or experience muscle cramps even if they have been drinking water regularly.

Warning Signs Not to Ignore¹˒²

Even when staying hydrated, an electrolyte imbalance may cause:

• Unusual fatigue or weakness
• Muscle cramps
• Headaches
• Dizziness

These warning signs should not be ignored, particularly among older adults, children, and athletes, who are more vulnerable during periods of extreme heat.

Staying Properly Hydrated During a Heatwave²

To effectively compensate for losses caused by sweating:

1. Drink regularly, without waiting until you feel thirsty, as thirst is already a sign that dehydration has begun.
2. Eat foods naturally rich in minerals, such as fruits (bananas, apricots), vegetables, and dairy products.
3. Avoid overly sugary or alcoholic beverages, which can worsen dehydration.
4. Use appropriate hydration solutions when needed, especially those containing electrolytes.

Hydrafizz, UPSA’s effervescent hydration solution, combines water, sugar, and electrolytes to help support optimal hydration, even during periods of intense sweating.

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