Which vitamin is fat-soluble and can accumulate to toxic levels if consumed in excess?

• A. Vitamin C
• B. Vitamin D
• C. Vitamin A
• D. Vitamin K

Answer: (C)

Fat-soluble vitamins are stored in the liver and body fat, so taking them in amounts consistently higher than needed can lead to buildup and toxicity over time. Vitamin A is a classic example of this risk: when consumed in excess, especially as supplements or high-dose retinol, it can accumulate and cause liver damage, skin changes, bone and joint pain, and in pregnancy, birth defects. Acute overdose can bring about nausea, dizziness, and headaches. While other fat-soluble vitamins can also be toxic at very high intakes (like vitamin D), this option is the best illustration of the toxicity risk from excess consumption. Vitamin C is water-soluble and is typically excreted, not stored, so it’s less prone to accumulation.