Now Magnesium 400mg Capsules provide a mineral that is critical for energy production and metabolism, muscle contraction, nerve impulse transmission, and bone mineralization. Magnesium is required as a cofactor for over 300 enzymes involved in protein synthesis, glucose metabolism, and fatty acid synthesis. It helps regulate calcium balance, supports cardiovascular and nervous system function, and acts as a natural calcium blocker to help muscles relax. Magnesium deficiency can lead to muscle weakness, cramps, and spasms. It contributes to bone strength, flexibility, and helps prevent injury by loosening tight muscles. Adequate intake supports blood sugar balance, blood pressure regulation, and overall cellular function.