Why do I get leg cramps at night, and do electrolytes help?

Short answer. Most night leg cramps are not caused by one missing mineral, and electrolytes are not a guaranteed fix. The honest position is that the evidence is mixed. Topping up sodium, potassium, and magnesium supports normal muscle function and is reasonable if you have been sweating hard, eating low-sodium, fasting, or drinking a lot of plain water. It will not reliably stop cramps that come from posture, age, or causes nobody can pin down. If your cramps are frequent, severe, or new, that is a conversation for a doctor, not a supplement.

So, do electrolytes actually help?

Sometimes, for some people, and not as a cure. Marketing likes to promise that one scoop of minerals ends cramping. The research is less sure. Reviews of magnesium for ordinary night cramps in older adults have generally found little benefit over a placebo. Studies on exercise cramps have moved away from the old story that you are simply dehydrated, toward muscle fatigue and nerve signalling as the bigger drivers. So electrolytes can be part of the picture, mostly when your intake has genuinely been low. Anyone selling them as a switch that turns cramps off is overselling. We would rather tell you that.

Why do legs cramp at night in the first place?

Often the boring truth is that nobody knows. Nocturnal leg cramps, usually in the calf or foot, are common, and they get more common with age. A large share of adults over 60 report them. The leading explanations are muscle fatigue, the way motor nerves fire when a muscle is held short, and long periods of sitting or standing. The position your foot rests in under the duvet, with the toes pointed, shortens the calf and can set one off. None of those causes is solved by adding salt to water.

What electrolytes actually do for muscles

Sodium, potassium, and magnesium are the minerals your nerves and muscles use to contract and relax. Sodium and potassium move across cell membranes to carry the electrical signal. Magnesium contributes to normal muscle function and to normal energy metabolism. If those minerals are genuinely depleted, that signalling works less smoothly. That is the mechanism people are reaching for when they reach for electrolytes. The catch is that most people eating a normal diet are not badly depleted, so the effect of topping up is small unless you have been losing or skipping a lot.

When it might actually be a hydration or mineral issue

There are situations where your minerals really can run low, and replacing them is sensible:

• Heavy sweating. You lose roughly 0.5 to 1.5 g of sodium per litre of sweat. Long sessions in heat add up quickly.

• Low-sodium or whole-food diets. Cut processed food and your sodium intake can drop below what your body is used to.

• Fasting and keto. Lower insulin makes your kidneys shed more sodium and water, which is why people feel flat without replacing it.

• A lot of plain water. Drinking heavily with no sodium dilutes what you already have.

In those cases an unflavoured electrolyte serving is a reasonable thing to add. It is not a treatment. It is replacing what left.

When it is probably not your electrolytes

If you eat normally, drink normally, and still cramp at night, more salt will likely do little. Age, long hours on your feet, pregnancy, some medications, and plain idiosyncrasy all show up as cramps, and none of them are a sodium shortage. Stretching the calf before bed and keeping the foot in a neutral position tends to help more than any powder. Cramps that are frequent, one-sided, or new deserve a doctor rather than a guess.

How much sodium, potassium, and magnesium is reasonable?

For context, one Boring serving is 3.5 g of powder with 1000 mg sodium, 200 mg potassium, and 60 mg magnesium. The 60 mg of magnesium is a sensible share of a day, not a mega-dose, because there is no strong evidence that loading magnesium stops ordinary cramps anyway. Potassium has a daily reference intake near 2000 mg, and most of that should come from food. Sodium is the one people on clean diets most often run short of when they sweat. The point of an electrolyte mix is steady replacement, not a spike.

So what should I do tonight?

Keep it boring. Drink to thirst across the day rather than chugging a litre at bedtime. If you have been sweating, fasting, or eating low-sodium, add a serving of electrolytes earlier in the day rather than as a 2 a.m. rescue. Stretch your calves before bed. Do not point your toes under tight sheets. And do not expect a mineral powder to fix a cramp that was never about minerals.

Common versions of this question

• Will magnesium stop my night cramps? Maybe not. Trials of magnesium for ordinary nocturnal cramps in older adults mostly show little benefit beyond placebo, so it is worth trying but not worth banking on.

• Are leg cramps a sign I am dehydrated? Not necessarily. Dehydration is only one possible factor, and most night cramps happen for reasons unrelated to how much you drank.

• Do I need salt before bed for cramps? Only if your sodium has genuinely been low, for example after heavy sweat or a low-sodium day. Otherwise extra salt at night does little.

• What is the best electrolyte for cramps? There is no proven best for cramps, because cramps have many causes. A simple, full-dose, unflavoured mix replaces what you lose without sugar or additives.

The boring answer

If your cramps line up with heavy sweating, heat, fasting, or a low-sodium week, the reasonable move is steady electrolyte replacement, and that is what Boring Electrolytes is built for. Three ingredients, full doses, nothing else: 1000 mg sodium, 200 mg potassium, and 60 mg magnesium per serving, 60 servings for €24, about €0.40 each. No sugar, no flavours, no claims it cannot keep. It will not promise to cure a cramp, because honest replacement is the only thing minerals can actually do.

Unflavoured. On purpose. boringelectrolytes.com