Sodium: What It's Good For

You're standing in the supermarket in front of two cases of mineral water — one labeled "200 mg sodium per liter," the other "low sodium" — wondering which one is actually the better choice. Here's the short answer: sodium isn't an additive you should avoid. It's a mineral that literally nothing in your body can run without — it controls your fluid balance, your blood pressure, and every single nerve impulse you have. Whether extra sodium in your water helps you or is simply unnecessary depends on how much you're already losing or taking in through sweat, food, and everyday life. This guide breaks down what sodium actually does in your body, when high-sodium water works in your favor — and when you're better off reaching for the low-sodium bottle instead.

What Is Sodium?

Sodium is a mineral and, chemically speaking, an alkali metal. It doesn't show up in your body as a metal, though — it exists dissolved as a charged particle, the sodium ion (Na⁺), which together with potassium forms the single most important electrolyte pair in your system. Through food, you take in sodium almost entirely as table salt (sodium chloride), plus whatever occurs naturally in mineral water — anywhere from under 5 to over 1,000 milligrams per liter, depending on the source. Your body can't produce sodium on its own; like every essential mineral, you have to supply it, whether through solid food or through what you drink.

What Sodium Actually Does in Your Body

Sodium is the dominant mineral outside your cells — in your blood plasma and in the fluid between cells. It acts like a magnet for water: wherever sodium collects, fluid follows. That's exactly how your body regulates how much volume is circulating in your blood vessels — which directly determines your blood pressure. Drink liters of pure, sodium-free water and you dilute that level, so your body tends to flush the water back out instead of holding onto it. That's why plain water isn't automatically the best choice after heavy fluid loss — sodium is what keeps the water where you actually need it.

Sodium's second major job happens at every single cell membrane in your body: the sodium-potassium pump. It constantly shuttles sodium out of the cell and potassium in, building up an electrical charge that's the foundation for every nerve impulse and every muscle contraction you have, from your heartbeat to the blink of an eye. This mechanism runs around the clock and, in the process, burns through roughly a third of the energy your cells use at rest — so sodium isn't a footnote, it's one of the biggest line items in your entire metabolism. A third job: sodium also escorts glucose and amino acids through your intestinal wall into your bloodstream. That's why electrolyte drinks with a pinch of salt work noticeably better than plain sugar water.

Who Should Pay Attention to This?

For most people eating a normal diet, sodium deficiency simply isn't an issue — if anything, it's the opposite, more on that below. Whether high-sodium water actually benefits you or is just unnecessary depends on your specific situation:

• Exercise and heavy sweating: On long runs, bike rides, or training sessions in the heat, you lose a noticeable amount of sodium through sweat. High-sodium water replaces it automatically while you're drinking anyway.
• Low blood pressure: If you deal with low blood pressure and circulation issues regularly, a bit more sodium can genuinely help — it keeps more fluid in your bloodstream and helps stabilize your pressure.
• Low-carb, keto, or fasting: When your insulin level drops, your kidneys excrete more sodium. One extra glass of high-sodium water a day easily offsets that.
• High blood pressure, kidney, or heart conditions: The rule flips here — low-sodium water (under 20 mg/l) is the better choice, since extra sodium can push fluid retention and blood pressure even higher.
• Baby formula: Low-sodium water is specifically intended for preparing bottles — an infant's immature kidneys can't handle high amounts yet.

For everyone else — most healthy adults with no underlying conditions — it barely matters whether the mineral water in your fridge has 50 or 400 milligrams of sodium per liter. Your kidneys handle that balance reliably on their own.

Intake & Dosage

The benchmark for adequate intake is around 1,500 milligrams of sodium a day for healthy adults. Through bread, cheese, cold cuts, and a completely normal diet, you hit that amount easily — usually well beyond it, in fact, since processed foods tend to be generously salted.

Mineral water can be a surprisingly big lever here, precisely because you're drinking it anyway. A high-sodium water with around 700 milligrams per liter delivers 1,400 milligrams over two liters — nearly your entire daily amount, without deliberately adding any salt. If you're also losing extra sodium — exercise in the heat, fasting, low-carb — that's an easy, passive way to make up for it. For everyone else, it's simply a bonus your kidneys balance out without any trouble.

If you want to dose sodium more deliberately — around a long training session, say — it's best to spread the intake over time rather than drinking it all at once, and ideally pair it with potassium, since the two electrolytes work as counterparts at the same cell membrane. Either way, keep this in mind: sodium doesn't replace fluid, it just makes sure fluid stays where you need it — so keep drinking enough water regardless.

What to Look for When You Buy

When you're choosing a water, a glance at the label tells you more than any marketing claim. This figure is legally regulated, not just marketing copy: a water may only call itself "low sodium" if it contains under 20 milligrams of sodium per liter — a threshold set by Germany's Mineral and Table Water Ordinance, covering sodium in all its chemical forms, not just as table salt. From roughly 200 milligrams per liter up, a water is commonly considered high in sodium, or labeled as "contains sodium." Most bottles on the shelf fall somewhere in the broad middle between those two marks.

• For exercise, heat, and low-carb diets: Deliberately choose a water with a higher sodium value (200 mg/l and up) instead of a low-mineral still water.
• If you have high blood pressure, kidney, or heart issues: Stick consistently with the low-sodium option (under 20 mg/l) — and take a look at processed foods too, since they usually contribute far more sodium than a glass of water ever will.
• For food labels in general: If the packaging lists "salt" instead of "sodium," just divide the value by 2.5 to get the actual sodium amount.

If you'd rather not leave your sodium intake to chance through water consumption, and instead want a targeted, measured dose around exercise or hot days, a well-balanced electrolyte product is the more practical solution than drinking liters of high-sodium water and hoping for the best — more on that in a moment.

The Honest Take

Sodium is a special case among minerals. With almost every other nutrient, the worry is "am I getting enough" — with sodium, it's usually the reverse: the vast majority of people already get more than they need through processed food alone. For healthy people, high-sodium mineral water is therefore neither a danger nor a miracle fix — it's just one of many sodium sources alongside bread, cheese, and cold cuts, and in the overall balance, it's usually minor compared to what ends up on your plate.

The exceptions remain the situations where you demonstrably lose more than usual — endurance sports, heat, fasting — or where you have health reasons to take in less. If you have high blood pressure or a kidney or heart condition, talk through the right water amount and type with your doctor instead of deciding by feel.

Matching Products from Scheunengut

If you recognize yourself in any of the situations above — lots of exercise, hot days, low-carb, or fasting — our Electrolyte Complex is the controlled alternative to grabbing whatever water bottle happens to be at hand. It combines sodium with magnesium, potassium, calcium, and chloride in a clearly declared amount per tablet, with no added sugar. That way you know exactly how much you're taking in, instead of guessing from labels or drinking liters of high-sodium water — practical for your gym bag, everyday heat, or life on the go.

Frequently Asked Questions (FAQ)

What does the body need sodium for?

Sodium controls your fluid balance and, with it, your blood pressure. As the sodium-potassium pump, it drives every nerve impulse and muscle contraction you have, and it also shuttles glucose and amino acids into your bloodstream. Without sodium, literally no nerve or muscle in your body works properly.

Is high-sodium mineral water healthy?

For most healthy adults, yes — your body reliably manages any excess sodium through your kidneys. High-sodium water is especially useful if you exercise a lot, deal with heat, follow a low-carb diet, or have low blood pressure; if you have high blood pressure, kidney disease, or heart disease, the low-sodium option is the better choice.

How can I tell if a water is low or high in sodium?

The figure is listed on the label under mineral content. Legally, a water can only be called "low sodium" if it contains under 20 milligrams of sodium per liter; from roughly 200 milligrams per liter up, it's commonly considered high in sodium.

Does high-sodium water raise blood pressure?

In healthy people with no pre-existing conditions, the small amount of sodium in a glass of water is unlikely to have a noticeable effect compared to what you get from bread, cheese, and ready meals. If you're already salt-sensitive or have high blood pressure, though, low-sodium water is still the safer choice.

Why do you sometimes crave something salty?

When your sodium level drops noticeably — after heavy sweating, say, or a few days of low salt intake — it often shows up as a specific craving for salty food. It's a simple regulatory mechanism your body uses to restore its balance.

What happens in the body when sodium is too low?

If your blood sodium level drops significantly, water shifts into your cells, which can lead to headaches, weakness, nausea, or muscle cramps. Through normal eating habits, this is extremely rare — it becomes relevant almost exclusively with very high losses, like hours of sweating combined with drinking a lot of plain water.

Is sodium in mineral water the same as salt in food?

Chemically related, but not packaged identically: table salt is sodium chloride, while in mineral water, sodium is often dissolved as bicarbonate or sulfate as well. For your sodium balance, what ultimately counts is the total amount from all sources combined, regardless of its chemical form.