The mineral crucial for muscle contraction and nerve function is calcium. Calcium plays a key role in the process of muscle contraction by allowing the interaction between actin and myosin proteins within muscle fibers. Additionally, calcium is essential for transmitting signals in the nervous system, enabling communication between nerves and muscles. Sufficient calcium intake is vital for overall body function, and sources include dairy products, leafy greens, nuts, and fortified foods. Ensuring optimal calcium levels can support both muscular and neurological health.