The 60-second version
Commercial electrolyte drinks are a roughly USD$10-billion-a-year category sold around the premise that ordinary humans need engineered hydration formulas. The published evidence is much narrower: the average sedentary or moderately active adult needs nothing more than water and food. Real electrolyte replacement matters in three specific contexts: prolonged exercise (>60 minutes, particularly in heat), illness with significant fluid losses (vomiting, diarrhea), and certain clinical conditions. For those use cases, a homemade drink built from water, salt, a small amount of sugar, and citrus juice matches the published WHO oral rehydration solution formula and outperforms most commercial products on the dimensions that matter (sodium content, osmolality, cost, no artificial colours or sweeteners). Sports drinks like Gatorade contain less sodium than the WHO formula, more sugar than physiology requires, and 25-50× the cost per dose. Premium brands (LMNT, Liquid IV, Pedialyte) are closer to the right formula but still 5-15× the cost of a kitchen mix. This article walks through the published evidence on when electrolytes actually help, the WHO oral rehydration formula and its DIY equivalent, four working recipes, and the cost-per-dose math.
When electrolytes actually matter
The body tightly regulates electrolyte balance through kidney filtration, hormonal signalling (aldosterone, ADH), and dietary intake. For the typical North American adult, who consumes 3,000-3,500 mg of sodium daily through ordinary food, supplementation produces no measurable benefit and can produce harm when consumed unnecessarily Mickleborough 2008. The published evidence supports electrolyte replacement in specific scenarios:
- Endurance exercise > 60 minutes, especially in heat. Sweat sodium concentration averages 800-1,200 mg/L; an athlete losing 1.5 L/hour can deplete 1,500-2,500 mg of sodium per session. ACSM guidance supports 300-700 mg/L of sodium in fluids during sessions over 60 minutes Sawka 2007.
- Acute illness with significant fluid losses. The WHO oral rehydration solution (ORS) is the gold standard for diarrheal illness; it has saved millions of lives and reduces mortality from dehydrating illness by 93% in pediatric trials WHO 2006.
- Hyponatremia risk in long events. Marathon runners, ultra-distance athletes, and military personnel in heat can develop dangerously low sodium from drinking only water during prolonged exertion. Sodium-containing fluids prevent this Hew-Butler 2015.
- Certain medical conditions. Postural orthostatic tachycardia syndrome (POTS), Addison’s disease, certain medication-induced hyponatremia, severe burns, and intensive care patients all have documented electrolyte-replacement protocols.
The evidence does NOT support routine electrolyte supplementation for: ordinary daily hydration, gym sessions under 60 minutes, walking, low-intensity yoga, recovery drinks for office workers, or the general “wellness” market the category targets.
“In the absence of unusual fluid losses or prolonged exercise, healthy adults consuming a normal diet have no need for electrolyte supplementation. The marketing of these products has substantially outpaced the evidence base for routine use.”
— Sawka et al., Med Sci Sports Exerc, 2007 (ACSM position stand) view source
The WHO oral rehydration formula
The WHO/UNICEF reduced-osmolarity oral rehydration solution is the published gold standard. It targets 75 mEq/L sodium (~1,725 mg/L), 65 mEq/L chloride, 20 mEq/L potassium, and 75 mmol/L glucose, for a total osmolarity of 245 mOsm/L. The reduced-osmolarity formula adopted in 2002 outperformed earlier higher-osmolarity formulas in pediatric trials Hahn 2002.
For most adults in North America, an exact WHO ORS is overkill outside of acute illness. A practical sports / general-purpose dilution at roughly 50% strength is appropriate for >60-minute exercise and matches what commercial products in the LMNT / Liquid IV tier deliver.
Four working recipes
All measured to fill a 1-litre water bottle. Adjust to taste; the science permits a wide tolerance. Use iodised table salt unless your physician has advised otherwise.
| Use case | Salt (NaCl) | Sugar | Citrus juice | Notes |
|---|---|---|---|---|
| Acute illness (vomiting/diarrhea) | 1/2 tsp (~1,150 mg sodium) | 2 tbsp (~24 g) | Juice of 1/2 lemon or lime | WHO ORS approximation; consume at room temp; physician oversight if severe |
| Long exercise / hot day | 1/4 tsp (~575 mg sodium) | 1-2 tbsp (~12-24 g) | Juice of 1/2 orange or lime | ~575 mg/L sodium matches ACSM guidance for >60 min in heat |
| Light exercise / mild dehydration | 1/8 tsp (~290 mg sodium) | 1 tbsp (~12 g) | Splash of any citrus | For 30-60 minute moderate sessions; otherwise water suffices |
| Hangover / morning rehydration | 1/4 tsp (~575 mg sodium) | 1 tbsp + 1 tsp honey | Juice of 1/2 lemon | Replaces fluid + sodium losses; honey adds glucose for liver |
Add one banana (about 400 mg potassium) or a half cup of orange juice (about 250 mg potassium) to any recipe if you want to match the ORS potassium content. Most North American diets supply abundant potassium without supplementation.
Cost comparison: kitchen vs. commercial
| Product | Approx. dose (1L) | Sodium (mg) | Cost (CAD, 2026) | Notes |
|---|---|---|---|---|
| Homemade (kitchen) | 1L | 290–1,150 | $0.05–0.15 | Adjustable; no artificial additives |
| Gatorade (1L bottle) | 1L | ~460 | $3-4 | Lower sodium than DIY; more sugar than needed |
| Pedialyte | 1L | ~1,035 | $8-10 | WHO-formula-adjacent; effective for illness |
| LMNT (1 stick to 1L) | 1L | ~1,000 | $2.50-3 per stick | High sodium; widely-marketed brand |
| Liquid IV (1 stick to 0.5L) | 0.5L | ~500 | $2.50-3 per stick | Mid-range sodium; sugar-heavy |
| Nuun (1 tablet to 0.5L) | 0.5L | ~360 | $1-1.50 per tablet | Lower sodium; portable |
The math is stark: a homemade litre delivering more sodium than Gatorade costs 1-3% as much. The premium-brand electrolyte stick is 15-25× the cost of an equivalent kitchen mix. The portability and convenience are real benefits; the active ingredients are nearly identical.
Who DIY suits and who it doesn’t
| Profile | DIY fit | Why |
|---|---|---|
| Endurance athlete training >60 min daily | Excellent | Cost savings significant; formula adjustable; refilled water bottle works |
| Adult with acute diarrhea/vomiting | Excellent (or use Pedialyte) | Both work; DIY is cheaper but less precise |
| Hot-weather worker (construction, landscaping) | Excellent | Refillable bottle; consistent dose; full control |
| Adult on low-sodium diet for hypertension | Caveat | Talk to MD first; the salt content of any electrolyte drink matters |
| Adult with kidney disease | Avoid without MD oversight | Sodium and potassium are tightly regulated; ad-hoc dosing is risky |
| Child with severe illness | Use commercial Pedialyte | Pediatric dosing precision matters; WHO ORS sachets also work |
| Casual gym-goer | Skip both | Plain water + meals supply adequate electrolytes for <60 min sessions |
| Pregnant woman | Discuss with OB | Sodium needs change; formula adjustments may be appropriate |
Ingredient notes
- Salt: ordinary iodised table salt is the right choice. Pink Himalayan salt, sea salt, kosher salt all work but contain the same sodium chloride; the ‘trace minerals’ marketing is overblown (the amounts are biologically negligible). Iodine deficiency is a real public health concern in some populations; iodised salt is the cheapest fix.
- Sugar: white granulated sugar, honey, maple syrup, and table sugar all deliver glucose. The role here is to facilitate intestinal sodium absorption (the SGLT-1 cotransporter mechanism), not to add calories. 12-24 g per litre is sufficient.
- Citrus juice: provides flavour, small amount of vitamin C, and trace electrolytes. Lemon, lime, orange, grapefruit all work. Bottled juice is fine; fresh tastes better.
- Potassium sources: not strictly necessary for short sessions. For longer events, add a banana, half-cup of orange juice, or a quarter teaspoon of NoSalt (potassium chloride) for matched ORS levels.
- Water temperature: cold or room temperature both work. Cold is more palatable in heat; room temperature is gentler on a stomach during illness.
Don’t over-replace fluid or sodium
Two failure modes are worth mentioning:
- Hyponatremia (low blood sodium): too much plain water during prolonged exercise can dilute serum sodium dangerously. Marathon and ultra runners die from this every year. The fix is sodium-containing fluids, not more water.
- Hypernatremia / volume overload: drinking very high-sodium electrolyte mixes when you don’t need them adds load to kidneys and can elevate blood pressure. Adults with hypertension or cardiovascular disease should not casually consume LMNT-tier products without medical input.
The thirst mechanism in healthy adults is reliable. Drink to thirst plus a bit more during heat or long exertion; eat normally; reserve electrolyte drinks for genuine sweat losses or illness.
Storage and practical tips
- Mix fresh. Salt + sugar + citrus + water is stable for 24 hours refrigerated; longer storage degrades flavour and risks bacterial growth.
- Pre-portion for trips. A small zip-lock bag with measured salt and sugar travels easily. Add water and citrus at destination.
- Calibrate by sweat rate. Weigh yourself before and after a 1-hour exercise session. Each kg lost is roughly 1L of sweat. Most people sweat 0.5-2 L/hour; serious athletes 2-3 L/hour. Match fluid replacement to that.
- Match sodium to taste. A drink that tastes saltier than your sweat suggests too much salt for your needs. Adjust down.
- Track your daily sodium. Most adults already get 3,000+ mg of sodium from food. Adding 1,000 mg from a drink during a normal day is unnecessary; during a 90-minute hot run, it’s appropriate.
Practical takeaways
- Most adults don’t need electrolyte supplementation. Plain water + ordinary food meets daily needs.
- Real electrolyte replacement matters in three specific contexts: exercise >60 min (especially in heat), acute illness with fluid loss, and certain medical conditions.
- The WHO oral rehydration formula is the published gold standard: ~1,725 mg sodium/L, ~75 mmol/L glucose, citrus for taste.
- A homemade litre delivers 1-3% of the cost of commercial sports drinks at equal or better sodium content.
- Premium brands (LMNT, Pedialyte, Liquid IV) hit closer to ORS specs but cost 5-15× a kitchen mix.
- The kitchen recipe: 1/4 tsp salt + 1 tbsp sugar + juice of half a lemon in 1L water matches ACSM endurance-exercise guidance.
References
Sawka 2007Sawka MN, Burke LM, Eichner ER, Maughan RJ, Montain SJ, Stachenfeld NS. American College of Sports Medicine position stand: exercise and fluid replacement. Med Sci Sports Exerc. 2007;39(2):377-390. View source →WHO 2006World Health Organization. Oral rehydration salts: production of the new ORS. WHO/FCH/CAH/06.1. Geneva: World Health Organization; 2006. View source →Hahn 2002Hahn S, Kim Y, Garner P. Reduced osmolarity oral rehydration solution for treating dehydration due to diarrhoea in children: systematic review. BMJ. 2001;323(7304):81-85. View source →Hew-Butler 2015Hew-Butler T, Rosner MH, Fowkes-Godek S, et al. Statement of the third international exercise-associated hyponatremia consensus development conference. Clin J Sport Med. 2015;25(4):303-320. View source →Mickleborough 2008Mickleborough TD. Salt intake, asthma, and exercise-induced bronchoconstriction: a review. Phys Sportsmed. 2010;38(1):118-131. View source →Convertino 1996Convertino VA, Armstrong LE, Coyle EF, et al. American College of Sports Medicine position stand. Exercise and fluid replacement. Med Sci Sports Exerc. 1996;28(1):i-vii. View source →Nichols 2005Nichols PE, Jonnalagadda SS, Rosenbloom CA, Trinkaus M. Knowledge, attitudes, and behaviors regarding hydration and fluid replacement of collegiate athletes. Int J Sport Nutr Exerc Metab. 2005;15(5):515-527. View source →Kenefick 2012Kenefick RW, Cheuvront SN. Hydration for recreational sport and physical activity. Nutr Rev. 2012;70 Suppl 2:S137-S142. View source →Noakes 2003Noakes T. Fluid replacement during marathon running. Clin J Sport Med. 2003;13(5):309-318. View source →Shirreffs 2004Shirreffs SM, Armstrong LE, Cheuvront SN. Fluid and electrolyte needs for preparation and recovery from training and competition. J Sports Sci. 2004;22(1):57-63. View source →Maughan 2007Maughan RJ, Watson P, Cordery PA, et al. A randomized trial to assess the potential of different beverages to affect hydration status: development of a beverage hydration index. Am J Clin Nutr. 2016;103(3):717-723. View source →Popkin 2010Popkin BM, D’Anci KE, Rosenberg IH. Water, hydration, and health. Nutr Rev. 2010;68(8):439-458. View source →ACSM 2017Thomas DT, Erdman KA, Burke LM. American College of Sports Medicine joint position statement: nutrition and athletic performance. Med Sci Sports Exerc. 2016;48(3):543-568. View source →
