Do You Need to Drink Electrolytes Every Day?

It depends on what the day takes out. On an ordinary day with three meals the sodium is already in your food: adults in England average 8.4 g of salt a day against the NHS maximum of 6 g. The days that call for more are the ones that take electrolytes out faster than meals put them back: an hour or more of sweaty exercise, which costs about a gram of sodium an hour on average, hot weather, and a day when you eat very little, whether through illness, a GLP-1 medicine or a hard cut in calories; vomiting and diarrhoea are a pharmacy rehydration sachet's job.^{1, 2, 3} This is the daily-use spoke of the Wellgard electrolytes guide.

Is it OK to drink electrolytes every day?

It depends on what the rest of your day is doing. The national sodium survey of 2018 to 2019 measured salt in the urine of nearly 600 adults in England, and put the average at 8.4 g a day, 40% above the 6 g maximum: 9.2 g for men and 7.6 g for women, three quarters of it inside bread, cereals, cheese, bacon and ready meals before anyone reaches for a salt cellar.^{1, 2} So the daily question is not whether you are getting enough sodium. It is whether today is one of the days that drains it.

Those days are specific. In 506 athletes, sweat sodium averaged about 0.8 g per litre, at sweat rates averaging 1.2 litres an hour: an hour of hard exercise in the heat costs the average person about a gram of sodium.³ Vomiting and diarrhoea lose sodium, potassium and chloride with the fluid, and the NHS points anyone with dehydration signs to a pharmacist for an oral rehydration sachet.⁵ A day of eating very little removes the salt that meals supply: the product information for tirzepatide (Mounjaro) tells patients to take precautions to avoid fluid depletion and electrolyte disturbances, and we cover that case in do you need electrolytes on Mounjaro?.⁶ Daily training in heat, kitchen or site work in summer, the recovery days after a stomach bug, a week of 900-calorie days: each is a daily electrolyte case while it lasts; on a commute-and-sandwich day the meals have done most of the work and a low-sodium sachet is the size that fits.

How much salt is in an electrolyte sachet?

Enough that it belongs in the day's total. Sodium times 2.5 gives salt, and the NHS maximum of 6 g of salt is 2.4 g of sodium.² A low-sodium daily sachet carries around 300 mg of sodium, which is 0.75 g of salt, an eighth of the 6 g maximum, usually with some potassium and magnesium, and where the magnesium reaches 15% of the reference intake it contributes to electrolyte balance; a high-sodium sachet built for heavy sweating carries around 2 g of sodium, which is about 5 g of salt, about 80% of the 6 g maximum in one 500 ml drink, with more potassium and magnesium to match. A low-sodium sachet on a day of soup and dry toast adds 300 mg of sodium to a day the meals have left short. A high-sodium sachet adds the sodium of two litres of average sweat, so it is sized for the day when two litres of sweat have gone, a long hot run or an afternoon of site work in heat, in an adult without kidney or blood-pressure problems; the low-sodium sachet is sized for the day when they have not.

For scale, the foods highest in sodium in the UK composition tables are the cured and the processed: grilled back bacon at about 1,400 mg per 100 g, ham at 800 mg, Cheddar at about 720 mg, white bread at 400 mg.⁷ Two slices of white toast carry about as much sodium as a Daily sachet; add two rashers of bacon and the plate is at roughly three times it. A sachet is not uniquely salty. It is salt you can count.

Who benefits from a daily sachet?

People whose every day is one of the draining days. Someone training an hour or more most days in warm conditions. Someone whose job keeps them sweating. Someone in the first weeks of a GLP-1 medicine or any very low-intake diet, eating a few hundred calories of plain food and so missing the dietary salt; for them the low-sodium sachet is sized for the day; the Intense one is sized for the long, hot session. Someone recovering from a stomach bug for the two or three days appetite takes to return. Older people deserve a mention because thirst dulls with age and the NHS lists relying on others for drinks among the dehydration risks, but they are also the group most likely to be on a diuretic, an ACE inhibitor or a potassium-sparing medicine, so for them the question starts with the pharmacist.⁵

Can electrolytes affect your kidneys or blood pressure?

Sodium can, in proportion to your starting point. The 2020 Cochrane review of 195 trials found that cutting sodium from about 4.7 g to 1.5 g a day lowered systolic blood pressure by about 1 mmHg in people with normal blood pressure and by nearly 6 mmHg in people with hypertension; the European Food Safety Authority sets a safe and adequate adult intake at 2.0 g of sodium a day.^{8, 9} A daily high-sodium sachet in someone with high blood pressure, heart failure or kidney disease is the wrong tool.

Potassium runs the other way. In a dose-response analysis of 32 trials, extra potassium lowered blood pressure up to a difference of about 30 mmol a day and raised it above about 80 mmol a day in people taking blood-pressure medicines; the 492 mg in an Intense sachet is about 13 mmol.¹⁰ The firm caution is chronic kidney disease and the medicines that stop the kidneys shedding potassium, an ACE inhibitor such as ramipril or lisinopril, an angiotensin receptor blocker such as losartan or candesartan, spironolactone or amiloride, where high blood potassium is common and can be dangerous.¹¹ The "puffy fingers" some people report after starting sachets is sodium doing its ordinary job of holding water: a few hundred millilitres of extra fluid, often with the scales half a kilogram up, which the kidneys pass over a day or two once the sodium stops. If it does not pass, or comes with breathlessness, see your GP.

How do you tell if you are having too many?

The signs are ordinary. Too much sodium shows as thirst, swollen fingers and ankles and a creeping blood-pressure reading. Too much potassium from supplements shows first in the stomach, as pain, nausea and diarrhoea; the dangerous version, high blood potassium, is silent until it affects the heart rhythm.^{4, 11} Too much magnesium, above about 400 mg a day from supplements, is a laxative.⁴ The mirror image matters too: drinking large amounts of plain water lowers blood sodium, and in long events over-drinking is the documented danger. Of 488 runners at the 2002 Boston Marathon, 13% finished with low blood sodium; the 2015 consensus advice is to drink to thirst.^{12, 13} An electrolyte drink is not a licence to drink more.

Who should check with a pharmacist first?

Anyone with high blood pressure, heart failure or kidney disease, because of the sodium. Anyone on an ACE inhibitor, an angiotensin receptor blocker, spironolactone, amiloride or a prescribed potassium supplement, because of the potassium.¹¹ Anyone on a diuretic. Anyone pregnant or breastfeeding, as the label says. And anyone using a pharmacy rehydration sachet should know its own conditions: not for self-treatment in kidney disease or diabetes, and under-twos only under a doctor.⁶

Frequently asked questions

How often should you drink electrolytes?

As often as you have a draining day: an hour or more of sweaty exercise, heat, the recovery days after a stomach bug or a day of eating very little. On a normal day with normal meals the sodium is already there.^{1, 3}

Is four electrolyte sachets a day too much?

Yes. Four low-sodium sachets add 3 g of salt to an intake that already averages 8.4 g, and one high-sodium sachet can be nearly 5 g on its own; labels say one a day for a reason.^{1, 2}

Can drinking lots of water reduce your sodium?

It can. Blood sodium falls when water intake outruns losses, and marathon runners who gained weight during the race were four times more likely to finish with low sodium; drink to thirst.^{12, 13}

Do bananas help lower sodium?

Not lower it, but a banana's 330 mg of potassium counts towards the 3,500 mg a day the NHS recommends; potatoes, pulses and milk count the same way.^{4, 7}

What is the best electrolyte to take daily?

The one sized for your day: a low-sodium sachet for a light-eating or warm desk day, a high-sodium one only for the day that has cost two litres of sweat.^{3, 7} Which drinks contain electrolytes? compares the options.

Who should not take salt tablets?

People with high blood pressure, heart failure or kidney disease, anyone on a diuretic, and anyone not actually losing litres of sweat; the 2015 hyponatraemia consensus advises drinking to thirst rather than salt loading.^{8, 13}

Sources

1. Public Health England. National Diet and Nutrition Survey: assessment of salt intake from urinary sodium in adults aged 19 to 64 in England, 2018 to 2019. gov.uk.
2. NHS. Salt in your diet. nhs.uk/live-well/eat-well/food-types/salt-in-your-diet.
3. Baker LB, et al. Normative data for regional sweat sodium concentration and whole-body sweating rate in athletes. Journal of Sports Sciences, 2016. PubMed 26070030.
4. NHS. Vitamins and minerals: others. nhs.uk/conditions/vitamins-and-minerals/others.
5. NHS. Dehydration. nhs.uk/conditions/dehydration.
6. Summaries of Product Characteristics for tirzepatide (Mounjaro), section 4.4, and for a UK pharmacy oral rehydration sachet, via the MHRA products database. products.mhra.gov.uk.
7. Public Health England. McCance and Widdowson's Composition of Foods Integrated Dataset (CoFID), 2021. gov.uk.
8. Graudal NA, Hubeck-Graudal T, Jurgens G. Effects of low sodium diet versus high sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterol, and triglyceride. Cochrane Database of Systematic Reviews, 2020. PubMed 33314019.
9. EFSA Panel on Nutrition, Novel Foods and Food Allergens. Dietary reference values for sodium. EFSA Journal, 2019. PubMed 32626425.
10. Filippini T, et al. Potassium intake and blood pressure: a dose-response meta-analysis of randomized controlled trials. Journal of the American Heart Association, 2020. PubMed 32500831.
11. Sarnowski A, et al. Hyperkalemia in chronic kidney disease: links, risks and management. International Journal of Nephrology and Renovascular Disease, 2022. PubMed 35942480.
12. Almond CS, et al. Hyponatremia among runners in the Boston Marathon. New England Journal of Medicine, 2005. PubMed 15829535.
13. Hew-Butler T, et al. Statement of the 3rd International Exercise-Associated Hyponatremia Consensus Development Conference, 2015. British Journal of Sports Medicine, 2015. PubMed 26227507.

This article is general information, not medical advice. If you have high blood pressure, heart failure or kidney disease, or take a diuretic, an ACE inhibitor, an angiotensin receptor blocker, spironolactone, amiloride or a potassium supplement, ask a pharmacist or your GP before using any electrolyte product, and call 111 if dehydration signs do not settle or fluids will not stay down.