Which of the following vitamins is used to enhance the absorption of Calcium?

SCTIMST Staff Nurse - 2015 (Set-B)

Applied Nutrition & Dietetics

Easy

Appeared in: SCTIMST Staff Nurse - 2015 (Set-B)

Explanation

Vitamin D is a fat-soluble vitamin that plays a crucial role in calcium homeostasis.
It is converted to its active form, calcitriol (1,25-dihydroxycholecalciferol), in the kidneys.
Calcitriol acts on the cells of the small intestine to increase the production of calcium-binding proteins.
These proteins facilitate the active transport of calcium from the food we eat into the bloodstream, thereby enhancing its absorption.
This function is essential for maintaining adequate calcium levels for bone mineralization, nerve function, and muscle contraction.

Option A: Vitamin E is a powerful antioxidant that protects cell membranes from oxidative damage. It has no direct function in the absorption or metabolism of calcium.
Option C: The Vitamin B complex (e.g., B1, B2, B6, B12) is a group of water-soluble vitamins primarily involved in energy metabolism, red blood cell formation, and neurological functions. They do not play a direct role in calcium absorption.
Option D: Vitamin A is a fat-soluble vitamin crucial for vision (especially night vision), immune system function, and maintaining healthy skin and mucous membranes. It is not involved in enhancing calcium absorption.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Role of vitamins in mineral absorption as background academic context rather than a clinical decision trigger.
Nurses often educate patients with or at risk for osteoporosis to take calcium supplements in combination with Vitamin D to maximize absorption and improve bone density.
Vitamin D deficiency is common, especially in older adults, individuals with limited sun exposure, and those with certain malabsorption syndromes. Screening and supplementation are key preventive measures.
What if? If a patient has chronic kidney disease, their ability to convert Vitamin D to its active form (calcitriol) is impaired. This leads to decreased calcium absorption, low serum calcium, and secondary hyperparathyroidism, which worsens bone disease. These patients often require supplementation with active Vitamin D (calcitriol) directly.

How to Approach the Question

First, identify the core of the question: it asks which vitamin helps the body absorb calcium.
This is a factual recall question common in nursing exams, testing fundamental knowledge of nutrition and physiology.
Mentally review the primary functions of each vitamin listed in the options.
Recall that Vitamin D is uniquely linked to bone health and the regulation of calcium and phosphorus.
Eliminate the other options based on their main roles: Vitamin A for vision, Vitamin E as an antioxidant, and B-complex vitamins for metabolism and nerve function.
Select Vitamin D as the correct answer because its primary physiological role includes facilitating calcium absorption in the intestines.

Concept Tested & Keywords

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