Electrolyte drinks are booming – but do you actually need them?

They used to mainly be associated with sports and recovery from illness.

But electrolyte drinks are booming in popularity, with UK supermarkets seeing a rapid rise in demand. That's despite expert advice that most healthy adults don't need them.

Sainsbury's reports a 333% rise in searches for "rehydration sachets" over the past year, while Waitrose has seen a 171% increase in searches for "electrolytes". Tesco says it has nearly quadrupled its electrolyte range over the same period.

The trend is hard to miss on social media too – if we're not scrolling past influencers drinking them we're noticing branded adverts selling them.

No longer just sold as sachets or soluble tablets, electrolytes are being added to canned drinks and other products now, too.

Electrolyte drinks are designed to replace minerals like sodium and potassium that are lost through illness, sweat and prolonged exercise.

But experts say water and a balanced diet are all most healthy adults need to stay well hydrated and maintain healthy electrolyte levels.

So is the hype worth it, and do these products really carry health benefits?

They're minerals that have an electrical charge when dissolved in liquid. Sodium, potassium, calcium, chloride and magnesium are all electrolytes that our bodies need to function.

They help your muscles to contract and help keep your heart and nervous system healthy. But it's their role in hydration that seems to have earned them so much recent airtime.

Electrolyte drinks

Sports drinks

"Electrolyte drinks are not inherently more hydrating than water for the average person," says dietitian Nichola Ludlam-Raine, external, who notes water is "perfectly adequate" to keep your body well hydrated day to day.

She goes on to say, though, that if you've lost a significant amount of fluid and electrolytes (through excessive sweating, prolonged exercise or vomiting, say) drinks containing sodium can help the body absorb and retain fluid better than plain water.

Most of us, then, will not benefit from including these electrolyte products in our daily routine.

The good news is that most people get enough electrolytes from a balanced diet that includes whole grains, nuts, seeds, beans, pulses, fruit and vegetables.

If you're low on electrolytes or they're significantly imbalanced, you might experience symptoms like fatigue, headaches, dizziness, muscle cramps, weakness, nausea, confusion and an irregular heartbeat.

If this happens often, see a doctor – especially if you've been ill.

In rare cases, low sodium can cause a condition called hyponatraemia. One cause is when endurance athletes drink a lot of plain water which dilutes the sodium in their blood.

Although some people attribute their tiredness to low sodium, Ludlam-Raine says this is usually caused by a medical issue rather than not drinking electrolytes.

In fact, most people in the UK already consume more than the recommended maximum of 6g (one teaspoon) of salt per day.

If you're experiencing vomiting or diarrhoea, your body may have lost fluid and electrolytes. For this, the NHS recommends, external an oral rehydration solution. These contain electrolytes alongside glucose, external, which helps you absorb sodium and water.

We all know that drinking too much alcohol can dehydrate you, external and make you feel depleted. But while electrolyte drinks might support your recovery, they're far from a hangover cure, says Ludlam-Raine.

Instead, she recommends sleep, food and time as the things that help the most with a hangover, alongside water. Above all though, prevention is far more effective than any supposed cure.

You might have noticed electrolytes being used to support breastfeeding: some brands market electrolytes specifically for this cause.

While it's important to drink more fluids, external if you're breastfeeding, there's currently no evidence to show that electrolytes will be more effective than water, says Ludlam-Raine.

"There's no good evidence that electrolyte drinks are routinely needed, or that drinking extra fluid beyond thirst improves milk supply, external."

How about claims that drinking electrolytes could help manage sugar cravings, external? Again, this isn't based on any hard evidence, Ludlam-Raine warns.

"Sometimes people mistake thirst, tiredness or irregular eating for cravings. Being well hydrated and eating regular balanced meals may help, but electrolytes themselves are not a proven craving-control tool."

In addition to when you're recovering from sickness or diarrhoea, electrolytes might be helpful if you're an exercise enthusiast.

But before you stock up, Prof Mayur Ranchordas, external, a specialist in sports nutrition, suggests you consider the intensity and duration of your workout.

After a moderate intensity workout for less than an hour, you typically don't need an electrolyte drink, he says. But this might change if you're exercising in hot or humid conditions and losing electrolytes in your sweat.

"If you get salty sweat marks on your clothing after exercise, you are likely to be a salty sweater, which means you lose a lot of sodium in your sweat."

In this case, electrolyte drinks can help replenish the lost sodium.

If you're exercising for more than 90 minutes, you might want to think about drinking a sports drink. They contain electrolytes, as well as sugar for energy (whereas electrolyte drinks are typically low in calories, external).

People who work outdoors or exercise during heatwaves may need to think about replenishing fluids and electrolytes more than the rest of us, too.

The good news is that you don't have to spend a fortune on sports drinks. You can make your own. Ludlam-Raine suggests mixing up this simple recipe:

• 500ml water

• 500ml unsweetened fruit juice (such as orange juice)

• ¼ teaspoon salt

Generally, your kidneys do a good job of getting rid of excess electrolytes, unless you have kidney disease.

Too much sodium may contribute to raised blood pressure, and too much potassium or magnesium can be dangerous. Again, this is especially relevant if you have kidney disease or take certain medications.

It's also worth noting that some drinks come with quite a lot of sugar, while others are sweetened with low-calorie sweeteners.

For the vast majority of us, regularly drinking electrolyte-enhanced products is totally unnecessary.

Drinking water is often the best way to stay hydrated, while eating a varied, healthy balanced diet will give you all the electrolytes you're likely to need on an average day.

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