Calcium is the most abundant mineral found in our bodies and performs many vital roles. It is necessary for bone health, cardiovascular and muscle function, and nervous system signalling. Calcium also acts as a coenzyme for many metabolic processes in the body. Calcium is often most closely associated with the skeletal system, as it is critical for developing and maintaining bone structure and function. Ninety-nine percent of all the calcium in our body is stored within our bones, which act as a reservoir for calcium, releasing more of the mineral when it is needed. Only one percent of body calcium is found outside of the skeletal system; this amount is regulated and kept consistent by the body and does not fluctuate with changes in calcium intake.

Our bodies are unable to produce calcium on their own, so we need to obtain the additional calcium our bodies need through our diets. Calcium-rich food sources include dairy products, green cruciferous vegetables, and fortified foods such as juices and cereals. Calcium is also available as a dietary supplement. Vitamin D plays a significant role in absorbing calcium from the gastrointestinal tract, so it is important to have adequate amounts of both nutrients to support optimal health.

Cardiovascular and Muscular Health

Calcium is essential for proper muscle contraction, including the beating of the heart. Its presence acts as a signal for the muscle fibers to enable the contraction cycle when a muscle is stimulated. Calcium is also involved in blood clotting, by acting as a cofactor for several enzymes involved in the cascade of events needed to begin and maintain the clotting process. Additionally, calcium is responsible for the dilation and contraction of blood vessels.

Through its actions as a messenger between cells and tissues, calcium is involved in the transmission of nerve signals throughout the body. It also plays a role in hormone secretion.

Bone Development and Growth

One of the most important roles of calcium is assisting with bone development, growth, maintenance, and overall structure. Peak bone mass is achieved around the age of 30, at which point bone density is gradually lost due to a continued need for stored calcium for body functions. People who do not consume an adequate amount of calcium before they reach their peak bone mass are at a higher risk of later developing osteoporosis - a disease characterised by low bone density and quality - due to smaller calcium reserves.