Calcium & Magnesium By NOW Overview & Drug Interactions

Calcium is a vital nutrient found in various foods such as dairy products, certain vegetables, and many fortified items. Over 99% of the body's calcium is stored in the bones and teeth, predominantly as hydroxyapatite. The remaining calcium circulates in the blood, extracellular fluid, muscles, and other tissues, where it is essential for processes like nerve signaling, muscle contraction, vascular activities, glandular secretion, and maintaining cell membrane and capillary permeability. It also plays critical roles in enzyme reactions, respiration, kidney function, and blood clotting, and is involved in neurotransmitter and hormone release, amino acid uptake, vitamin B12 absorption, and gastrin secretion. Calcium balance changes with age: it is positive during periods of growth, stable in adulthood, and tends to become negative in older age. Calcium loss occurs through feces, urine, sweat, and shedding skin cells. In women, reduced estrogen levels decrease calcium absorption and retention, increase bone turnover, and lead to lower bone mass. Calcium supplements come in various forms, including citrate and carbonate, which differ mainly in their calcium content and absorption rates. Calcium citrate is easily absorbed and can be taken without food, making it suitable for older adults or those with low stomach acid. In contrast, calcium carbonate, which contains a higher percentage of calcium, is best absorbed when taken with meals.

Magnesium is a mineral that is essential for the proper functioning of the body. It plays a role in many important physiological processes, including the contraction and relaxation of muscles, the transmission of nerve impulses, and the regulation of blood pressure. Magnesium is found in a variety of foods, including leafy green vegetables, nuts, and grains, and it is also available as a dietary supplement. There are several different forms of magnesium that are available as supplements, all of which can be used to prevent deficiency. Additionally, magnesium is purported to have several different health benefits, such as improving sleep, reducing muscle cramps, reducing anxiety, and preventing or treating migraines. Although magnesium is essential for health, magnesium-containing foods and supplements can interact with some prescription medications if used at the same time.