Summer is in full swing, and we’ve already seen three heat waves in the UK. Whether you're enjoying the outdoors, exercising, or working in the sun, staying hydrated becomes even more important.

You might be surprised at how quickly dehydration can set in. According to Dr. Corey Slovis, who is recognised for his expertise in resuscitation, emergency cardiac care, and heat- and cold-related illnesses, he has written and lectured extensively on dehydration, heatstroke, and electrolyte balance, particularly in the context of EMS (emergency medical services).  Just 30 minutes of outdoor exertion can lead to early dehydration. And by the time you feel thirsty, have a dry mouth or notice reduced urine output, mild dehydration may already have started.

Hydration is more than just drinking water

Water is essential, but it’s only part of the story. To properly absorb and use the water you drink, your body needs a balanced supply of electrolytes. These minerals help transport fluid into your cells and support muscle and nerve function.

When you sweat, especially in hot conditions, your body loses both water and electrolytes. Replacing only the water can dilute your body’s electrolyte balance, leading to symptoms like muscle cramps, fatigue and poor concentration.

The four key electrolytes to replace are:

• Sodium
• Potassium
• Magnesium
• Chloride

Together, they are essential for hydration, energy, muscle performance and recovery.

How much more should you drink in summer?

Your daily fluid needs increase significantly in hot weather or during physical activity. General guidance suggests around 2.0 L per day for women and 2.5 L for men. But during warmer months or periods of exertion, this isn’t enough.

As a guide:

• Add around 0.5 L of water per hour of moderate outdoor activity
• For more intense effort or prolonged exposure to heat, aim for 3.5 to 5.0 L (or more) throughout the day

But quantity isn’t everything, quality of hydration matters too. That means pairing water with electrolytes to ensure proper absorption and balance.

Support hydration with elete™ and Citrilyte™

elete™ Electrolyte Add-In and Citrilyte™ provide all four essential electrolytes in a pure, additive-free formula. Just add to your water bottle to support hydration, muscle function and energy throughout the day.

No sugar, no flavourings, just effective hydration that works as hard as you do.

Guidance based on recommendations from the European Food Safety Authority, the U.S. National Academies of Sciences, Engineering, and Medicine, and the American College of Sports Medicine.