Is magnesium supplementation necessary for athletic performance or non-athletic individuals, or is a balanced diet and regular electrolyte drink sufficient?

Magnesium Supplementation for Athletes and Non-Athletes: Evidence-Based Recommendations

Routine magnesium supplementation is not recommended for most athletes or non-athletic individuals with a balanced diet, as there is insufficient evidence supporting performance benefits in those with adequate magnesium status. 1

Magnesium Status and Requirements

General Population Requirements

• Recommended daily allowance: 350 mg for women and 420 mg for men 2
• Food sources rich in magnesium include:
  • Whole grains
  • Nuts and seeds
  • Leafy green vegetables
  • Legumes
  • Coffee and tea

Athletes and Exercise

• Exercise induces redistribution of magnesium in the body to accommodate metabolic needs 3
• Strenuous exercise may increase magnesium requirements by 10-20% due to increased urinary and sweat losses 3
• Minimum recommended intake for athletes:
  • 260 mg/day for males
  • 220 mg/day for females 3

Evidence on Supplementation

For Athletes

• UEFA expert guidelines indicate that micronutrient supplementation (including magnesium) should only be used when a specific deficiency is identified 1
• Supplementation benefits are primarily observed in magnesium-deficient individuals 3
• Athletes at highest risk for deficiency include:
  • Those in weight-control sports (wrestling, gymnastics) 3
  • Female athletes 4
  • Athletes with Black or Mixed-Race ethnicity 4
  • Those with restricted eating patterns 1

For Non-Athletes

• There is mixed evidence for magnesium supplementation to prevent muscle cramps in non-athletic populations 2
• Not recommended for idiopathic cramps in older adults or pregnancy-associated cramps 2

Testing and Monitoring

• Red Cell Magnesium testing is more accurate than serum levels for assessing status 4
• In a study of Olympic and Paralympic athletes, 22% were found to be clinically deficient in magnesium at least once over an 8-year period 4
• Normal plasma magnesium ranges: 1.5-2.5 mEq/L; deficiency: <1.3 mEq/L 2

Targeted Supplementation Approach

When to Consider Supplementation

1. Confirmed magnesium deficiency through testing
2. Athletes with high sweat rates or in weight-control sports
3. Individuals with restricted diets
4. Those with symptoms potentially related to low magnesium:
   • Muscle cramps
   • Tendon pain (athletes with Achilles or patella tendon pain had significantly lower magnesium levels) 4

Supplementation Protocol

• Oral supplementation with organic magnesium salts (aspartate, citrate, lactate) at 400-500 mg daily is preferred due to superior bioavailability 2
• Divide doses throughout the day to improve tolerance and absorption 2
• Target serum level: >0.6 mmol/L (>1.5 mg/dL) 2

Common Pitfalls and Cautions

1. Self-prescription without testing: Athletes who self-prescribe supplements are often those least likely to require them 1
2. Excessive supplementation: Can cause diarrhea, abdominal cramping, and nausea 2
3. Reliance on sports drinks alone: Regular electrolyte drinks may not contain sufficient magnesium to address deficiencies
4. Ignoring dietary sources: A "food first" approach is recommended before turning to supplements 1
5. Supplement contamination: Athletes should only use supplements from reputable suppliers to avoid contamination with prohibited substances 1

Conclusion

The evidence does not support routine magnesium supplementation for either athletes or non-athletes with adequate dietary intake. The "bro-science" recommendation that all athletes (particularly those in Brazilian Jiujitsu) must supplement with magnesium is not supported by scientific evidence. Instead, a targeted approach based on testing and individual risk factors is more appropriate, with supplementation reserved for those with confirmed deficiencies or specific risk factors.