Which of the following is NOT among the six nutrients whose absorption may be affected by regular alcohol intake?

• A. Vitamin B6
• B. Iron
• C. Vitamin A
• D. Thiamin

Answer: (C)

Regular alcohol use can disrupt the gut and liver in ways that affect the absorption of several nutrients, especially certain water-soluble vitamins and minerals. In common CNSC study materials, the nutrients whose absorption is most frequently impaired by regular alcohol intake include thiamin (B1), riboflavin (B2), niacin (B3), folate, vitamin B6, and iron. Vitamin A is not typically listed among these six, so it’s the one that does not belong in this group. Mechanistically, ethanol interferes with thiamin absorption and increases its loss, and it can alter iron absorption through gastric and intestinal changes. It also disrupts vitamin B6 metabolism and absorption. Vitamin A, being fat-soluble and closely tied to fat absorption and liver stores, is not as directly affected by alcohol intake in the same contexts used to identify the six nutrients, which is why it fits as the correct choice here.