To enhance absorption of calcium, which vitamin is needed?

DSSSB Public Health Nurse - 2015

Applied Nutrition & Dietetics

Easy

Appeared in: DSSSB Public Health Nurse - 2015

Explanation

Vitamin D is a fat-soluble vitamin that is essential for promoting calcium absorption in the gut and maintaining adequate serum calcium and phosphate concentrations.
It is converted to its active form, calcitriol (1,25-dihydroxycholecalciferol), in the kidneys.
Calcitriol functions as a hormone, binding to receptors in the intestinal cells to increase the synthesis of calcium-transport proteins like calbindin.
This mechanism enhances the efficiency of the small intestine to absorb dietary calcium, making it available for bone mineralization and other physiological functions.

Option A: Vitamin K is not primarily involved in the intestinal absorption of calcium. Its main role in bone health is to activate proteins, such as osteocalcin and matrix Gla-protein, which are necessary for binding calcium into the bone matrix.
Option B: Vitamin E is a powerful antioxidant that protects cells from damage. It has no established direct role in calcium absorption or bone metabolism.
Option D: Vitamin A is essential for vision, immune function, reproduction, and cellular communication. It does not play a direct role in enhancing the absorption of calcium from the intestines.

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 play a key role in educating patients about the importance of Vitamin D for bone health, especially in at-risk populations such as the elderly, postmenopausal women, and individuals with limited sun exposure.
Patient counseling should include dietary sources of Vitamin D (fatty fish, fortified milk, cereals), the benefits of sensible sun exposure, and the potential need for supplementation as prescribed.
Monitoring for signs of Vitamin D deficiency (e.g., bone pain, muscle weakness, fractures) is a crucial nursing assessment.

How to Approach the Question

First, identify the core of the question, which is the relationship between a specific vitamin and calcium absorption.
This is a factual recall question based on knowledge of vitamin functions.
Mentally review the primary functions of the fat-soluble vitamins listed in the options (A, D, E, K).
Recall that Vitamin D's most well-known function is its role in calcium homeostasis.
Eliminate the other options by recalling their main functions: Vitamin K for blood clotting and bone protein activation, Vitamin E as an antioxidant, and Vitamin A for vision and cell growth.
Select Vitamin D as the correct answer because it directly enhances the intestinal absorption of calcium.

Concept Tested & Keywords

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E6 One Stop Resource all for your Exam Needs in Biochemistry (pp 6-135 of 140) pp. 78-80, 76-78

E6 Biochemistry U Satyanarayana— Part 1 (pp 26-420 of 840) p. 150-152