A client experiencing headaches, constipation, muscle spasms, and hypertension is likely to have insufficient levels of which nutrient?

The symptoms described—headaches, constipation, muscle spasms, and hypertension—are closely associated with insufficient magnesium levels. Magnesium plays a critical role in various bodily functions, including muscle and nerve function, blood pressure regulation, and maintaining a healthy balance of electrolytes.

Headaches can occur due to muscle tension and vascular changes influenced by magnesium deficiency. Constipation may arise because magnesium is essential for proper muscle contractions in the digestive tract, facilitating movement and easing bowel movements. Muscle spasms are a direct consequence of inadequate magnesium, as the mineral is essential for muscle relaxation and the proper conduction of nerve impulses. Furthermore, hypertension can occur because magnesium helps regulate vascular tone; low levels can lead to increased blood pressure due to impaired relaxation of blood vessels.

In the context of this question, the identification of magnesium deficiency as the cause of the symptoms aligns well with its known physiological roles and the specific manifestations of deficiency. The other nutrients listed—calcium, sodium, and iron—do not directly correlate with the combination of symptoms presented in the same way as magnesium does, making magnesium the most likely candidate in this scenario.