Vitamin D deficiency is a common metabolic bone disorder that affects calcium balance, bone mineralization, and overall musculoskeletal health. Vitamin D plays a critical role in calcium absorption from the gastrointestinal tract and maintains normal bone structure. Deficiency leads to impaired bone mineralization, increasing the risk of fractures, bone pain, and muscle weakness.

Despite abundant sunlight, vitamin D deficiency is highly prevalent in the Middle East due to limited sun exposure, indoor lifestyles, skin coverage, and dietary insufficiency. Both adults and children are affected, making it a significant public health concern. Chronic deficiency contributes not only to bone disease but also to increased risk of falls and impaired muscle function.

In adults, prolonged vitamin D deficiency may lead to osteomalacia, a condition characterized by softening of bones due to defective mineralization. In children, it can cause rickets, resulting in skeletal deformities and impaired growth. Vitamin D deficiency is also commonly associated with osteoporosis and increased fracture risk in older adults.

Symptoms are often subtle or nonspecific and may include generalized bone pain, muscle aches, fatigue, and proximal muscle weakness. Because symptoms overlap with other conditions, deficiency frequently goes undetected without laboratory testing.

Diagnosis is based on measurement of serum 25-hydroxyvitamin D levels. Deficiency is classified based on established thresholds and helps guide treatment intensity. Assessment of calcium, phosphate, and parathyroid hormone levels may be necessary in more severe cases.

Management involves vitamin D supplementation, tailored to the severity of deficiency and individual patient factors. Adequate dietary calcium intake is essential to ensure effective bone mineralization. In addition to supplementation, safe sun exposure and lifestyle modification play supportive roles.

Correction of vitamin D deficiency improves bone strength, muscle function, and balance, reducing fracture and fall risk. Long-term maintenance therapy is often required, particularly in high-risk individuals.

Routine screening is recommended for individuals with osteoporosis, recurrent fractures, chronic kidney disease, malabsorption disorders, and limited sun exposure. Addressing vitamin D deficiency is a cornerstone of metabolic bone disease management and an essential component of preventive endocrine care.