What Are Electrolytes? A Complete 2026 Guide

By NUDAY Editorial · Reviewed by NUDAY Research Team · Last updated May 2026

"Electrolytes" is one of the most repeated words in wellness, sports nutrition, and supplement marketing. It's also one of the most poorly understood.

This guide explains what electrolytes actually are, what each one does in the body, how you lose them, when you need to replace them, and how to spot a real electrolyte product versus expensive flavoured water. Every claim is sourced to published research.

What exactly are electrolytes?

Electrolytes are minerals that carry an electric charge when dissolved in water — and that electric charge is what allows your body to run.

The body is fundamentally an electrical system. Every nerve impulse, every muscle contraction, every heartbeat depends on charged particles moving across cell membranes. Electrolytes are the particles that make that movement possible.

When you put salt in water, it dissolves into sodium ions (positively charged) and chloride ions (negatively charged). Those charged ions are what your body uses to move signals between cells, pull water into tissues, and contract muscle fibres. Pure water can't do any of this — it has no charge to carry.

According to a 2020 review published in StatPearls (used in medical training), electrolytes are essential for maintaining the resting membrane potential of every cell in the body. Without them, the entire system goes offline.

What do electrolytes do in the body?

Electrolytes are responsible for four core functions that keep you alive and functioning: hydration, muscle contraction, nerve signalling, and pH balance.

Here's what each function actually does:

• Hydration: Electrolytes create the osmotic gradient that pulls water into cells. Without them, water passes through your body without rehydrating you.
• Muscle contraction: Calcium triggers contraction, magnesium enables relaxation, and sodium/potassium control the signal that fires the muscle in the first place.
• Nerve signalling: Sodium and potassium pumping across nerve membranes is how your brain talks to the rest of your body.
• pH balance: Electrolytes buffer blood acidity. When the balance shifts, you feel fatigue, weakness, and brain fog.

Take any one of these offline and you feel it. Mild electrolyte imbalance shows up as headaches and cramps. Severe imbalance lands people in the emergency room.

What are the main electrolytes (and what each one does)?

The five main electrolytes are sodium, potassium, magnesium, calcium, and chloride — each with a distinct role and a documented clinical dose range.

Sodium

Sodium is the most important electrolyte for active hydration, responsible for water retention, blood pressure regulation, and nerve impulse transmission.

The 2017 ACSM position stand on fluid replacement identifies sodium as the primary mineral lost through sweat, with concentrations ranging from 200 to 2,000mg per litre depending on individual physiology and conditions. Daily intake targets for healthy adults sit between 1,500–2,300mg, but active people, hot-climate populations, and heavy sweaters often need more.

Underdosing sodium is the single biggest reason most electrolyte drinks fail to actually hydrate. NUDAY Daily Hydration Electrolyte Sticks deliver 600mg sodium per stick — the dose research uses, not the dose that fits a low-cost manufacturing brief.

Potassium

Potassium is the primary intracellular electrolyte, balancing sodium's extracellular role and supporting muscle function, heart rhythm, and blood pressure.

The recommended daily intake for adults is 3,500–4,700mg per day, with most coming from food (bananas, potatoes, leafy greens). Hydration products typically add 100–400mg per serving to support active needs. Imbalance shows up as muscle cramps, fatigue, and irregular heartbeat. NUDAY Daily Hydration includes 400mg potassium per serving.

Magnesium

Magnesium is a cofactor in over 300 enzyme reactions in the body, with central roles in muscle relaxation, energy production, and sleep quality.

Daily intake recommendations are 310–420mg per day depending on sex and age. Magnesium deficiency is one of the most common micronutrient gaps in modern diets, affecting roughly 50% of US adults according to 2018 USDA data. The form matters — magnesium oxide is cheap but poorly absorbed; magnesium bisglycinate, citrate, and L-threonate are the absorbable forms research uses.

Calcium

Calcium is the trigger that fires muscle contraction, the structural component of bones, and a key cofactor in blood clotting and nerve signalling.

Most calcium intake comes from food (dairy, leafy greens, fortified products), with daily targets of 1,000–1,200mg for adults. Hydration products usually add 50–100mg per serving for active needs. Calcium is often missing from cheap electrolyte products — NUDAY Daily Hydration includes 100mg per stick.

Chloride

Chloride is the negatively-charged partner to sodium, working together to maintain fluid balance, stomach acid production, and the body's overall electrical neutrality.

Daily intake sits around 2,300mg for adults and is almost always paired with sodium in salt-containing foods. Many electrolyte products skip chloride entirely or add it as an afterthought. NUDAY Daily Hydration includes 500mg chloride per serving as part of a complete five-mineral profile.

How do you lose electrolytes?

Electrolyte loss happens through three main channels — sweat, urine, and metabolism — and the rate accelerates with heat, activity, illness, and certain medications.

The major sources of electrolyte loss:

• Sweat: The biggest controllable loss. One litre of sweat can contain 200–2,000mg sodium, 100–300mg potassium, and trace amounts of magnesium and calcium.
• Urine: Baseline daily loss for normal kidney function is roughly 1,000–3,000mg sodium and 1,500–3,000mg potassium.
• Diarrhoea or vomiting: Can deplete electrolytes faster than any other route — one of the leading causes of clinical electrolyte imbalance worldwide.
• Diuretics and certain medications: Including some blood pressure drugs, caffeine in large amounts, and alcohol.
• Heat exposure: Even at rest, hot climates increase sodium loss through skin evaporation and sweat.

This is why people in hot climates, on long flights, doing physical work, or recovering from illness need more than basic dietary intake. Your daily sodium target floats — it's not a fixed number.

What are signs of electrolyte imbalance?

Electrolyte imbalance shows up as a recognisable cluster of symptoms — fatigue, headaches, muscle cramps, dizziness, brain fog, and irregular heart rhythm — before it becomes medically dangerous.

Common signs that one or more electrolytes are low:

• Headaches that don't respond to drinking more plain water
• Muscle cramps, particularly in the calves or feet
• Persistent fatigue without obvious cause
• Dizziness when standing up
• Brain fog and difficulty concentrating
• Nausea
• Heart palpitations or irregular rhythm
• Excessive thirst that doesn't resolve with water
• Dark or sparse urination despite normal fluid intake

Mild imbalance corrects with food and proper hydration. Persistent symptoms — particularly heart-related ones — warrant a medical check. Severe imbalance can be life-threatening and requires emergency care.

Do you actually need electrolyte supplements?

Most people get baseline electrolytes from food, but supplementation becomes valuable during active, hot, travel, training, or recovery situations where intake from diet alone falls short of demand.

Situations where electrolyte supplementation actually helps:

• Exercise lasting more than 30 minutes, particularly in heat
• Hot-climate living, even at rest
• Physically demanding work (hospitality, construction, hands-on roles)
• Travel days, especially long flights
• Recovery from illness involving fluid loss
• Long social nights or broken sleep
• Low-carb or fasting protocols (electrolyte loss accelerates without insulin signals)
• Pregnancy and breastfeeding (under medical guidance)

Situations where they're unnecessary:

• Light indoor activity with normal eating
• Cooler climates with no physical exertion
• Right after a balanced meal containing salt and vegetables

The honest answer: electrolytes are situational, not daily, for most people. NUDAY Daily Hydration is built for the days you actually need it — not as a daily compulsion.

What's the difference between electrolytes and minerals?

All electrolytes are minerals, but not all minerals are electrolytes — the distinction is whether the mineral carries an electric charge when dissolved in water.

Minerals are the broader category. Iron, zinc, copper, selenium, and many others are essential minerals but they don't function as electrolytes — they have different roles (iron carries oxygen, zinc supports immunity, etc.).

The minerals that DO function as electrolytes are the ones that ionize in body fluids: sodium, potassium, calcium, magnesium, chloride, bicarbonate, and phosphate. Of these, the first five are the ones that matter for daily hydration and the ones you find in well-formulated hydration products.

What's the best electrolyte ratio for hydration?

The optimal hydration ratio used in clinical research and the WHO oral rehydration formula prioritises sodium as the dominant electrolyte, with smaller proportional amounts of potassium, magnesium, calcium, and chloride.

Electrolyte	Per serving (clinical target)	Most market products
Sodium	500–1,000mg	100–200mg
Potassium	200–400mg	50–100mg
Magnesium	100–200mg	Trace or missing
Calcium	50–100mg	Missing
Chloride	300–600mg	Often missing

This is the ratio research uses. Most commercial electrolyte drinks fail at the first criterion (sodium dose) and skip half the other minerals entirely.

How does NUDAY Daily Hydration compare?

Ingredient	NUDAY Daily Hydration	Market Average
Sodium	600mg	100–200mg
Potassium	400mg	50–100mg
Magnesium	120mg	Trace or missing
Chloride	500mg	Often missing
Calcium	100mg	Missing
Taurine	1,500mg	Not included
Betaine	1,000mg	Not included
Added sugar	0g	6–12g

NUDAY Daily Hydration Electrolyte Sticks deliver the full five-electrolyte profile at doses research actually uses — 600mg sodium per stick, taurine and betaine on top for performance, zero added sugar.

Frequently Asked Questions

What are the 7 main electrolytes?

The seven main electrolytes in the human body are sodium, potassium, calcium, magnesium, chloride, phosphate, and bicarbonate. For daily hydration and supplementation, the first five are the ones that matter most — sodium, potassium, magnesium, calcium, and chloride.

What are natural electrolyte sources?

The best natural electrolyte sources are salt (sodium and chloride), bananas and potatoes (potassium), leafy greens and seeds (magnesium), and dairy or fortified plant milks (calcium). Coconut water contains potassium but is too low in sodium to function as a true hydration drink.

Are electrolytes the same as salt?

Salt is one electrolyte source — providing sodium and chloride — but it doesn't cover the full electrolyte profile. True hydration requires sodium, potassium, magnesium, calcium, and chloride working together as a system.

How much electrolytes should I have per day?

Baseline daily electrolyte targets for healthy adults are roughly: 1,500–2,300mg sodium, 3,500–4,700mg potassium, 310–420mg magnesium, 1,000–1,200mg calcium, and 2,300mg chloride. Active people, hot-climate populations, and heavy sweaters often need more sodium specifically.

Can you get electrolytes from food alone?

Yes, for most sedentary or moderately active people. A balanced diet with salt, vegetables, fruit, dairy or alternatives, and whole grains will cover daily needs. Supplementation matters when sweat, heat, illness, training, or travel push losses above what food can replace.

What's the best electrolyte drink with no sugar?

Look for products with 500mg+ sodium, the full five-mineral profile, premium mineral forms (citrate, bisglycinate, not oxide), and zero added sugar. NUDAY Daily Hydration meets all four criteria at 600mg sodium per stick.

Do you need electrolytes if you're not exercising?

Not daily for most people. But yes if you're in a hot climate, on a long flight, recovering from illness, doing physical work, on a low-carb diet, or had a heavy night. Electrolytes are situational, not a daily compulsion for sedentary indoor lifestyles.

Can you have too many electrolytes?

Yes. Excess sodium can elevate blood pressure in salt-sensitive people. Excess potassium can affect heart rhythm. Excess magnesium causes diarrhoea. People with kidney issues, heart conditions, or specific medications should consult a doctor before adding electrolyte products.

Are electrolyte drinks better than water?

At rest, water alone is usually fine. Under sweat, heat, training, or travel, water alone doesn't replace the minerals you're losing. Electrolytes don't replace water — they make water work by keeping it inside cells where hydration actually happens.

How quickly do electrolytes work?

Sodium starts pulling water into cells within 15–30 minutes of consumption. For full rehydration after heavy depletion, allow 60–90 minutes plus continued fluid intake. Magnesium and calcium have longer-acting effects across the body's enzyme systems.

Key Takeaways

• Electrolytes are minerals that carry an electric charge when dissolved in water — the body's electrical system runs on them
• The five main electrolytes are sodium, potassium, magnesium, calcium, and chloride
• Sodium is the most important for active hydration; underdosing it is why most "hydration" drinks fail
• Clinical research uses 500–1,000mg sodium per serving — most commercial products deliver 100–200mg
• You lose electrolytes through sweat, urine, illness, heat, and certain medications
• Signs of imbalance include headaches, cramps, fatigue, dizziness, brain fog, and palpitations
• Electrolyte supplementation is situational (active, hot, travel, illness), not a daily must
• The form matters — magnesium bisglycinate beats oxide; calcium citrate beats carbonate
• NUDAY Daily Hydration delivers the full five-electrolyte profile at clinical doses, with zero added sugar

The bottom line

Electrolytes are the minerals that make your body work as an electrical system. Five of them matter most — sodium, potassium, magnesium, calcium, chloride — and you lose them faster than most people think.

The honest truth about the hydration category: most commercial products underdose the most important electrolyte (sodium) by 3 to 5 times what research uses, while loading up on sugar that works against hydration.

Read the label. Look for 500mg+ sodium and the full five-mineral profile. Skip anything with 8g of sugar dressed up as "hydration." You'll feel the difference within a week.

Try NUDAY Daily Hydration Electrolyte Sticks →

Sources & References

1. Shrimanker, I. & Bhattarai, S. (2023). "Electrolytes." StatPearls Publishing.
2. Sawka, M.N. et al. (2007). "Exercise and Fluid Replacement: ACSM Position Stand." Medicine & Science in Sports & Exercise, 39(2).
3. McDermott, B.P. et al. (2017). "National Athletic Trainers' Association Position Statement: Fluid Replacement for the Physically Active." Journal of Athletic Training, 52(9).
4. National Academies of Sciences (2005). "Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate." National Academies Press.
5. World Health Organization (2006). "Oral Rehydration Salts: Production of the new ORS." WHO/UNICEF Joint Statement.
6. USDA (2018). "What We Eat in America, NHANES." Food Surveys Research Group.