Nutrition and Diet Therapy Practice Test

Vitamin D is crucial for the absorption of calcium, playing a key role in maintaining proper calcium and phosphorus levels in the body. When the skin is exposed to sunlight, the body synthesizes vitamin D, which then facilitates the intestinal absorption of calcium. This process is vital for maintaining bone health and mineral balance. Without sufficient vitamin D, calcium absorption from food can be significantly impaired, leading to potential deficiencies that may affect bone density and health.

While other vitamins like A and K are important for various other functions in the body, they do not have a direct role in enhancing calcium absorption. Vitamin C is primarily known for its role in collagen synthesis and immune function. Thus, the effectiveness of calcium uptake relies heavily on adequate levels of vitamin D, underlining its critical importance in nutrition and diet therapy.