Linoleic (n-6) is an essential fatty acid. Which statement supports this?

• A. It can be synthesized by the body
• B. It must be obtained from the diet
• C. It is a saturated fat
• D. It is identical to oleic acid

Answer: (A)

The concept being tested is that essential fatty acids must come from the diet because the body cannot synthesize them in adequate amounts. Linoleic acid is an essential fatty acid in the omega-6 family, meaning humans lack the metabolic capability to produce it from other fats, so dietary intake is required. This is why the statement that supports its essential status is that it must be obtained from the diet. Linoleic acid is not made by the body, it is not a saturated fat, and it is not identical to oleic acid (which is a monounsaturated fatty acid, 18:1 n-9).