Best Electrolyte Supplements 2025
Evidence-based reviews of the top electrolyte supplements for hydration and athletic performance
Understanding Electrolytes
Electrolytes are minerals that carry an electrical charge and play essential roles in hydration, nerve function, muscle contraction, and pH balance. The primary electrolytes include sodium, potassium, magnesium, calcium, and chloride. During exercise, sweating, or heat exposure, the body loses electrolytes, particularly sodium, which must be replaced for optimal function.
Sodium is the most abundant electrolyte in sweat, with losses ranging from 400-2000mg per liter depending on individual sweat rate and genetics. Research shows that replacing sodium during prolonged exercise can maintain plasma volume, prevent hyponatremia, and support performance. Potassium and magnesium are lost in smaller amounts but remain important for muscle and nerve function.
The science of oral rehydration, originally developed by the World Health Organization, demonstrates that the combination of sodium and glucose enhances water absorption in the intestines through the sodium-glucose co-transport system. This is why some electrolyte products contain small amounts of sugar, while others remain carb-free for different use cases.
Important Note: For most people engaging in light to moderate activity in temperate climates, plain water is sufficient for hydration. Electrolyte supplementation becomes more relevant during prolonged exercise (over 60 minutes), intense sweating, heat exposure, or for athletes following low-carb diets who require higher sodium intake.
Quick Comparison
| Rank | Product | Sodium | Potassium | Price | Rating |
|---|---|---|---|---|---|
| #1 | LMNT Recharge Electrolyte Drink Mix LMNT | 1000mg | 200mg | $45-52 (30 servings) | ★4.7 |
| #2 | Liquid I.V. Hydration Multiplier Liquid I.V. | 500mg | 370mg | $25-30 | ★4.6 |
| #3 | Nuun Sport Electrolyte Tablets Nuun | 300mg | 150mg | $22-28 | ★4.5 |
| #4 | Ultima Replenisher Electrolyte Powder Ultima | 55mg | 250mg | $28-35 | ★4.5 |
| #5 | KEY NUTRIENTS Electrolyte Powder Key Nutrients | 1000mg | 400mg | $32-38 | ★4.4 |
LMNT Recharge Electrolyte Drink Mix
LMNT was formulated with input from exercise scientists to match actual electrolyte losses during sweating. The 1000mg sodium per serving reflects research on sweat composition, making it particularly effective for endurance athletes, those in hot climates, or people following low-carb diets who need higher sodium intake. The formula contains no sugar, artificial sweeteners, or fillers.
Electrolyte Profile
Key Features
- Science-backed sodium levels for rehydration
- Zero sugar, zero carbs
- Keto and paleo friendly
- Formulated based on actual sweat loss research
Pros & Cons
Pros:
- +High sodium matches real sweat losses
- +Clean ingredients without artificial additives
Cons:
- -Premium pricing
- -High sodium not needed for light activity
Liquid I.V. Hydration Multiplier
Liquid I.V. uses the science of oral rehydration therapy, combining glucose and sodium to activate the sodium-glucose co-transport system for enhanced water absorption. This makes it particularly effective for rapid rehydration. The added vitamins support overall wellness. The 11g of sugar per serving facilitates absorption but makes it less suitable for low-carb diets.
Electrolyte Profile
Key Features
- Cellular Transport Technology for absorption
- Contains glucose for sodium-glucose co-transport
- Vitamin C, B3, B5, B6, B12 added
- NSF certified
Pros & Cons
Pros:
- +Rapid absorption via glucose co-transport
- +Good electrolyte balance with vitamins
Cons:
- -Contains 11g sugar per serving
- -Not suitable for ketogenic diets
Nuun Sport Electrolyte Tablets
Nuun Sport provides a balanced electrolyte profile in a convenient effervescent tablet format. The 300mg sodium is appropriate for moderate exercise and daily hydration needs. With only 1g of sugar, it provides a light flavor without excess calories. The tablet format is highly portable, making it ideal for runners, cyclists, and travelers who want to carry electrolytes without bulk.
Electrolyte Profile
Key Features
- Effervescent tablets dissolve in water
- Only 1g sugar per serving
- Highly portable for travel
- Wide variety of flavors
Pros & Cons
Pros:
- +Convenient tablets are travel-friendly
- +Low calorie and low sugar
Cons:
- -Lower sodium than some competitors
- -Takes time to dissolve fully
Ultima Replenisher Electrolyte Powder
Ultima Replenisher offers a comprehensive mineral blend with six electrolytes including calcium, chloride, and phosphorus in addition to the standard sodium, potassium, and magnesium. The higher magnesium content is beneficial for those with low dietary intake. However, the very low sodium (55mg) makes it better suited for general daily hydration rather than intense athletic performance or heat exposure.
Electrolyte Profile
Key Features
- Six electrolytes plus trace minerals
- Zero sugar, zero calories
- Plant-based and vegan
- Non-GMO and gluten-free
Pros & Cons
Pros:
- +Comprehensive mineral blend
- +Clean ingredients without artificial additives
Cons:
- -Very low sodium for athletic use
- -Stevia taste not preferred by everyone
KEY NUTRIENTS Electrolyte Powder
KEY NUTRIENTS provides research-backed electrolyte ratios with 1000mg sodium, 400mg potassium, and 120mg magnesium. This profile matches actual sweat losses during intense exercise and is particularly beneficial for endurance athletes and those following ketogenic diets who require higher electrolyte intake. The clean formula contains no artificial ingredients, sweeteners, or fillers.
Electrolyte Profile
Key Features
- High sodium for serious athletes
- Zero sugar, zero artificial ingredients
- Optimal ratios for sweat replacement
- Third-party tested
Pros & Cons
Pros:
- +Evidence-based electrolyte ratios
- +High quality with clean ingredients
Cons:
- -Higher price point
- -High sodium may be excessive for light activity
Electrolyte Supplement Guide
Key Electrolytes Explained
Sodium
Sodium is the primary electrolyte lost in sweat and the most critical for maintaining fluid balance and plasma volume during exercise. Sweat sodium concentration ranges from 400-2000mg per liter depending on genetics and heat adaptation. Research in the Journal of the International Society of Sports Nutrition shows that sodium replacement during prolonged exercise helps maintain performance and prevent hyponatremia.
Potassium
Potassium is primarily an intracellular electrolyte important for nerve signaling and muscle contraction. While less is lost in sweat compared to sodium, potassium replacement supports overall electrolyte balance. Most people get adequate potassium from diet, but athletes with high sweat losses benefit from supplementation.
Magnesium
Magnesium supports muscle relaxation, energy production, and electrolyte balance. Many people have suboptimal magnesium intake from diet. Exercise increases magnesium requirements, and studies suggest that adequate magnesium may help reduce muscle cramping, though evidence is mixed.
Calcium and Chloride
Calcium is essential for muscle contraction and bone health. Chloride works with sodium to maintain fluid balance and is the primary anion in sweat. Most complete electrolyte formulas include these in appropriate amounts.
Evidence-Based Benefits
Enhanced Hydration During Exercise
Research published in Sports Medicine demonstrates that beverages containing sodium are more effective than plain water for maintaining hydration during prolonged exercise. Sodium helps drive water absorption in the intestines and promotes fluid retention.
Note: Benefits are most apparent during exercise lasting longer than 60 minutes or in hot environments where sweat losses are elevated.
Prevention of Hyponatremia
Hyponatremia, or low blood sodium, can occur during ultra-endurance events when athletes drink excessive amounts of plain water without electrolyte replacement. Studies in endurance athletes show that sodium supplementation prevents dangerous drops in plasma sodium concentration.
Note: This is primarily a concern for endurance athletes exercising for multiple hours, not typical gym-goers.
Muscle Cramp Reduction
While research is mixed, some studies suggest that electrolyte replacement, particularly sodium and magnesium, may help reduce exercise-associated muscle cramping. A study in the Journal of Athletic Training found that athletes prone to cramping had lower sodium levels in their sweat.
Note: Cramping is complex and multifactorial. Electrolytes may help some individuals but are not a universal solution.
Support for Ketogenic Diets
When following low-carb or ketogenic diets, the body excretes more sodium and water due to lower insulin levels and reduced glycogen stores. Research in metabolic journals shows that increasing sodium intake during keto adaptation can reduce symptoms of the "keto flu" and support adherence.
Choosing the Right Electrolyte Supplement
The best electrolyte supplement depends on your specific use case:
- •Endurance athletes and heavy sweaters: Choose products with 500-1000mg sodium per serving (LMNT, KEY NUTRIENTS)
- •Moderate exercise or daily hydration: Products with 200-500mg sodium are sufficient (Nuun, Liquid I.V.)
- •Rapid rehydration needs: Glucose-containing products enhance absorption (Liquid I.V.)
- •Ketogenic diets: Zero-carb, high-sodium options (LMNT, KEY NUTRIENTS)
- •General mineral support: Comprehensive blends with multiple minerals (Ultima)
Timing and Usage
Electrolytes can be consumed before, during, or after exercise depending on your needs. For workouts longer than 60 minutes, sipping an electrolyte beverage throughout exercise helps maintain hydration and performance. Pre-loading with sodium 2-4 hours before exercise in hot conditions can help optimize fluid balance.
For general daily hydration, electrolytes can be consumed with breakfast or throughout the day. Those following low-carb diets may benefit from 2-3 servings daily to replace increased sodium excretion.
Safety Considerations
Electrolyte supplements are generally safe for healthy individuals when used appropriately. However, excessive sodium intake can be problematic for those with certain medical conditions. Start with recommended doses and adjust based on your sweat rate, exercise intensity, and climate.
Who Should Avoid or Use Caution
- •Individuals with kidney disease should consult a doctor before using high-sodium products
- •Those with heart failure or hypertension on sodium-restricted diets need medical approval
- •People taking medications affecting electrolyte balance (diuretics, ACE inhibitors) should discuss with their healthcare provider
- •Those with hyperkalemia (high potassium) should avoid high-potassium electrolyte products
Medical Disclaimer: Electrolyte supplements are not intended to diagnose, treat, cure, or prevent any disease. While electrolyte replacement is beneficial during prolonged exercise or heat exposure, plain water is adequate for most people during normal daily activities. Severe dehydration or electrolyte imbalances require medical attention, not just supplementation.
Related Resources
Affiliate Disclosure: This page contains Amazon affiliate links. When you purchase through these links, we may earn a commission at no additional cost to you. This helps support our research and content creation. We only recommend products we believe offer value based on available evidence and user feedback.
Our reviews are based on published research, product specifications, user reviews, and industry standards. We maintain editorial independence and provide honest assessments regardless of affiliate relationships.