Essential fatty acid deficiency is associated with biliary atresia when which dietary condition is used?

• A. MCT oil predominant with adequate LCT formula
• B. MCT oil predominant without adequate LCT formula
• C. High-LCT formula
• D. No fat in the diet

Answer: (B)

Essential fatty acids must come from long-chain fats, which provide linoleic and alpha-linolenic acids necessary for cell membranes, skin, and growth. In biliary atresia, fat absorption is already impaired because bile flow is reduced, so fats that require bile (long-chain fats) are harder to absorb. Medium-chain triglycerides, on the other hand, are absorbed without bile and can supply energy, but they do not deliver essential fatty acids. If the diet is predominantly MCT oil with insufficient long-chain fat in the formula, the patient can develop essential fatty acid deficiency despite adequate calories. That’s why using MCT oil as the main fat source without enough long-chain fat is the setup that leads to EFAD in this context. Providing adequate long-chain fat or a formula richer in LCT helps prevent EFAD, whereas completely eliminating fat or relying solely on MCT without LCT increases the risk.