Magnesium is at the center of many processes that require the contraction and release of smooth and skeletal muscles. It is critical in the process of exhaling in the lungs, the relaxation of heart muscles, the self-regulation of blood pressure by blood vessels, and of course, the relaxation of your skeletal muscles. When the tissues in skeletal and smooth muscles contract together, they cause the lungs to exhale, the heart to squeeze blood from its chambers, and blood vessels to constrict. But they can’t contract continually, they need to release and relax, and this requires magnesium. All this happens through a process called nerve impulse contraction, and it’s essential to life. In addition to these critical functions, magnesium plays a role in several hundred biochemical processes, including the transformation of hormones, the activation of neurotransmitters, escorting minerals across cell membranes, carbohydrate and protein synthesis, and many others.THE BEST VITAMINS FOR OVER 50 YEARS: For more than five decades, Mason Natural has produced quality vitamin supplements under cGMPs (current Good Manufacturing Practices) and adhering to US guidelines. All ingredients and finished goods are subjected to rigorous analytical testing, inspections and quality auditing. NO BAD STUFF: Gluten Free. Soy Free. Guaranteed no added: Sugar, Yeast, Soy, Wheat, Dairy, Gluten, Fish, Tree Nuts, Peanuts, Egg, Fragrance, Artificial Colors or Flavors, Preservatives, Animal Products, Crustacean Shellfish. Sodium Free. ESSENTIAL NUTRIENT: Magnesium is at the center of many processes that require the contraction and release of smooth and skeletal muscles; it is critical in the process of the relaxation of heart and skeletal muscles as well as the self-regulation of blood pressure by blood vessels. EXTRA STRENGTH: Our 500 mg magnesium tablets may help support normal, healthy blood pressure, healthy responses to stress, and a state of relaxation. MAGNESIUM: Our extra strength once per day tablets are an essential nutrient and may help support a healthy heart, nervous system and overall health.Best Sellers Rank: See Top 100 in Health & Household. Product Benefits: Cardiovascular Health. Flavor: Unflavor. Unit Count: 100.00 Count. Item Form: Tablet. Brand: MASON NATURAL. International Shipping: This item can be shipped to select countries outside of the U.S. Domestic Shipping: Currently, item can be shipped only within the U.S. and to APO/FPO addresses. For APO/FPO shipments, please check with the manufacturer regarding warranty and support issues. Country of Origin: USA. : B0075GRMQW. Manufacturer: Gluten Free Palace - HPC. Date First Available: June 4, 2012. Item model number: 311845160119. Product Dimensions: 2.3 x 2.3 x 4.3 inches; 5.3 Ounces. Is Discontinued By Manufacturer: No.