Which of the following vitamin intakes usually enhances iron absorption?

Appeared in: BTSC Staff Nurse 30July-2025

Explanation

Vitamin C, or ascorbic acid, is the primary vitamin that enhances the absorption of non-heme iron, which is found in plant-based foods.
It functions as a reducing agent, converting the less absorbable ferric iron (Fe³⁺) into the more soluble and readily absorbable ferrous iron (Fe²⁺) within the intestine.
This action is particularly important for individuals on vegetarian or vegan diets, as non-heme iron is less bioavailable than the heme iron found in animal products.

Option A: Vitamin D's main function is to regulate calcium and phosphorus levels in the body, which is essential for bone health. It does not have a direct role in enhancing iron absorption.
Option B: Vitamin E is a fat-soluble antioxidant that protects cells from oxidative damage. It is not involved in the metabolic pathways of iron absorption.
Option C: While Vitamin A is essential for vision, immune function, and cell growth, and may play a minor role in mobilizing stored iron, it is not the primary nutrient that enhances the absorption of dietary iron.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Nutrient interactions and mineral absorption as background academic context rather than a clinical decision trigger.
Nurses should educate patients with iron-deficiency anemia to consume Vitamin C-rich foods (e.g., citrus fruits, tomatoes, bell peppers) or take a Vitamin C supplement along with their iron supplements to maximize absorption and effectiveness.
This dietary counseling is especially critical for at-risk populations such as pregnant women, vegetarians, and patients with chronic blood loss.
What if? If a patient is taking an enteric-coated iron supplement, the benefit of concurrent Vitamin C is reduced. The coating is designed to dissolve in the less acidic environment of the small intestine, bypassing the stomach where Vitamin C's reducing action is most effective.

How to Approach the Question

First, identify the key concept in the question: the enhancement of iron absorption.
This is a factual recall question related to nutrition and biochemistry.
Systematically review the primary function of each vitamin listed in the options.
Recall that Vitamin D is linked to calcium, Vitamin E is an antioxidant, and Vitamin A is for vision and immunity.
Remember the well-established link between Vitamin C (ascorbic acid) and increased absorption of non-heme (plant-based) iron.
Select the option that directly matches this known physiological interaction.

Concept Tested & Keywords

Q5jNGk3eUbtBk0Lt-CsNBH

E6 Physiology Ganong 27e Vol 2 Part 1 p. 34-36

E6 Pharmacology KD Tripathi OneStop 9e p. 174-176

Practise the full BTSC Staff Nurse 30July-2025

Attempt every question from this paper in a timed mock, then review the full solution for each one.