Vitamin D deficiency can manifest as:

• A. Hypotension
• B. Muscle weakness
• C. Decreased production and excretion of PTH levels
• D. Less than normal serum lipid levels

Answer: (B)

Vitamin D supports calcium absorption and calcium is essential for proper muscle contraction. When vitamin D is deficient, calcium absorption drops, which can lower serum calcium and trigger secondary hyperparathyroidism (increased PTH) to maintain calcium levels. This combination—less calcium available for muscles and the direct role of vitamin D in muscle function—leads to proximal muscle weakness and fatigue, a common presentation of deficiency. Hypotension isn’t a typical feature, and deficiency more often raises PTH rather than decreasing it; lipid levels aren’t a defining manifestation of this condition.