2026-06-17
Do You Actually Need Electrolytes?
Plain water is fine for most things. But if you're exercising in the heat, sweating heavily, or just feeling flat for no obvious reason, electrolytes are worth understanding.
Most people know they should drink enough water. Fewer people think about what’s actually in the water they’re losing — and that’s where electrolytes come in.
What electrolytes are
Electrolytes are minerals that carry an electrical charge when dissolved in water. The main ones relevant to hydration are sodium, potassium, magnesium and chloride. They regulate fluid balance inside and outside your cells, support muscle contraction and nerve signalling, and help your body actually absorb and retain the water you drink.
When you sweat, you lose all of these — not just water. Plain water replaces the fluid but not the minerals. That distinction matters more than most people realise.
When plain water isn’t enough
For most everyday activity, water is fine. But there are situations where replacing electrolytes alongside fluid makes a real difference:
Exercise lasting more than an hour. Particularly in warm weather, or any activity where you’re sweating noticeably. The longer and harder the effort, the more you’re losing.
Hot weather generally. You don’t have to be exercising. Spending a day in the heat — whether that’s a long walk, a festival, or just a warm commute — can deplete electrolytes enough to affect how you feel.
After illness. Vomiting and diarrhoea cause rapid electrolyte loss. This is why rehydration sachets contain salts, not just water.
When you feel flat but can’t explain it. Low-grade electrolyte depletion isn’t always obvious. Headaches, muscle cramps, fatigue that doesn’t shift with rest, and poor concentration can all be signs — particularly if you’ve been active or the weather’s been warm.
Why sodium matters more than people expect
Sodium gets a bad reputation in the context of diet, but in the context of hydration it’s the most important electrolyte to replace. It’s the primary mineral lost through sweat, and it plays a central role in fluid absorption — water follows sodium across the gut wall. Without adequate sodium, drinking more water can actually dilute your electrolyte levels further, which is why plain water alone isn’t ideal for rehydration after significant sweating.
This is the main reason commercial electrolyte products include sodium — not as a flavouring, but as a functional component.
What to look for in an electrolyte supplement
The market ranges from sensible to largely pointless. A few things worth looking for:
A meaningful sodium content. If sodium is low or absent, the product isn’t really doing the job.
Potassium and magnesium alongside sodium. These work together. Magnesium in particular supports muscle function and is commonly low in people who exercise regularly.
No added sugar. Sugar-based electrolyte drinks (most mainstream sports drinks) are designed for endurance athletes burning through glycogen. For everyday use or moderate exercise, they’re more sugar than you need.
Clean ingredients. Artificial sweeteners, colours and flavourings add nothing useful. A well-formulated electrolyte product doesn’t need them.
What we stock
We carry Viridian’s Electrolyte Fix across all three stores — a liquid concentrate with sodium, potassium and magnesium and no sugar or artificial additives. A small amount added to a water bottle is enough to make a noticeable difference during or after exercise, and it’s equally useful on hot days when you’re not training at all.
If you’re not sure whether electrolytes are relevant to what you’re experiencing, come in and ask. It’s a short conversation and often a simple fix.
- Roath: 95 Albany Road, CF24 3LP
- Canton: 124 Cowbridge Road East, CF11 9DX
- Royal Arcade: 8 Royal Arcade, Morgan Quarter, CF10 1AE