Magnesium is an essential ion involved in numerous physiological processes and is commonly deficient in older adults. This review explores the relationship between magnesium and the hallmarks of aging, including genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, altered intercellular communication, disabled autophagy, dysbiosis, and chronic inflammation. Magnesium deficiency has been linked to chronic inflammation and may contribute to age-related diseases. Maintaining optimal magnesium levels throughout life could be a safe and economical strategy for promoting healthy aging. Magnesium plays a crucial role in various cellular processes, including DNA stability, telomere maintenance, mitochondrial function, and immune response. It is involved in DNA repair, telomerase regulation, and epigenetic modifications. Magnesium deficiency is associated with increased oxidative stress, inflammation, and metabolic disorders. Magnesium supplementation has been shown to improve insulin sensitivity, reduce the risk of type 2 diabetes, and enhance mitochondrial function. Magnesium is also essential for stem cell function and immune response. The review highlights the importance of magnesium in maintaining healthspan and preventing age-related diseases. Further research is needed to fully understand the mechanisms linking magnesium to aging and to develop effective interventions for healthy aging.Magnesium is an essential ion involved in numerous physiological processes and is commonly deficient in older adults. This review explores the relationship between magnesium and the hallmarks of aging, including genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, altered intercellular communication, disabled autophagy, dysbiosis, and chronic inflammation. Magnesium deficiency has been linked to chronic inflammation and may contribute to age-related diseases. Maintaining optimal magnesium levels throughout life could be a safe and economical strategy for promoting healthy aging. Magnesium plays a crucial role in various cellular processes, including DNA stability, telomere maintenance, mitochondrial function, and immune response. It is involved in DNA repair, telomerase regulation, and epigenetic modifications. Magnesium deficiency is associated with increased oxidative stress, inflammation, and metabolic disorders. Magnesium supplementation has been shown to improve insulin sensitivity, reduce the risk of type 2 diabetes, and enhance mitochondrial function. Magnesium is also essential for stem cell function and immune response. The review highlights the importance of magnesium in maintaining healthspan and preventing age-related diseases. Further research is needed to fully understand the mechanisms linking magnesium to aging and to develop effective interventions for healthy aging.