Magnesium Supplementation as a Nutritional Intervention in Sarcopenia

Condition(s) studied

Investigational drug(s) / intervention(s)

Citrate Magnesium Supplementation: Participants assigned to the experimental arm will receive oral magnesium supplementation administered daily for 12 weeks. The intervention consists of magnesium citrate capsules providing a total daily dose of 400 mg of elemental magnesium. The supplement will be taken according to a standardized dosing schedule identical to that of the placebo group. Magnesium citrate was selected due to its favorable bioavailability. Participants, investigators, and outcome assessors will remain blinded to group assignment throughout the study. Adherence to the intervention will be assessed by capsule count at follow-up visits, and participants will be monitored regularly for tolerability and potential adverse events.

Placebo: Participants assigned to the placebo comparator arm will receive an oral placebo administered daily for 12 weeks. The placebo consists of capsules containing microcrystalline cellulose, an inert substance with no known physiological or therapeutic effects. The placebo capsules are identical in appearance, taste, and packaging to the magnesium supplement to ensure blinding of participants and investigators. The dosing schedule will be the same as that used in the experimental group. Adherence to the intervention will be monitored by capsule count at follow-up visits, and participants will be observed regularly for tolerability and safety.

Study summary

Sarcopenia is a progressive condition common in older adults and is characterized by loss of muscle strength, muscle mass, and physical performance. It is associated with an increased risk of falls, disability, reduced independence, and poorer quality of life. Nutritional interventions are recommended as part of sarcopenia management; however, evidence regarding the role of specific micronutrients remains limited. Magnesium is an essential mineral involved in muscle contraction, neuromuscular function, energy production, and inflammation regulation. Low magnesium status is frequent in older adults and may contribute to muscle impairment and physical decline.

This study aims to evaluate the effects of magnesium supplementation on muscle strength, muscle mass, and physical performance in older adults with sarcopenia living in the eastern Algarve region of Portugal. In addition, the study will assess the prevalence of low magnesium status and sarcopenia in this population.

The study will be conducted in two phases. In the first, observational phase, community-dwelling adults aged 70 years or older will be assessed for sarcopenia according to established diagnostic criteria. Blood samples will be collected to measure serum and erythrocyte magnesium levels and C-reactive protein as an inflammatory marker. Participants diagnosed with sarcopenia and presenting low magnesium levels will be eligible for the second phase.

In the second phase, eligible participants will be randomly assigned to receive either oral magnesium supplementation (400 mg/day of magnesium citrate) or a placebo for 12 weeks, in a double-blind and controlled design. After the intervention period, participants will be reassessed for muscle strength, muscle mass, physical performance, magnesium status, and inflammation.

The results of this study are expected to clarify the role of magnesium supplementation as a nutritional strategy in sarcopenia. Findings may contribute to improving nutritional recommendations and supporting interventions aimed at preserving muscle health, physical function, and quality of life in older adults.

Eligibility

Primary outcome measure(s)

• Muscle Strength — Baseline and 12 weeks
  Change in muscle strength assessed by handgrip strength using a calibrated handgrip dynamometer. Handgrip strength will be measured in a seated position, with the elbow flexed at 90 degrees, following standardized procedures. Three measurements will be performed on the non-dominant hand (or dominant hand if necessary), with the highest value recorded. Muscle strength will be evaluated at baseline and after 12 weeks of intervention.
• Muscle Mass — Baseline and 12 weeks
  Change in muscle mass assessed by bioelectrical impedance analysis, including appendicular muscle mass and muscle mass adjusted for height. Measurements will be performed at baseline and after 12 weeks of intervention.
• Physical Performance — Baseline and 12 weeks
  Change in physical performance assessed by the 4-meter gait speed test, conducted according to standardized procedures. Performance will be assessed at baseline and after 12 weeks of intervention.

Trial sites (1)

Other trials for the same condition