Which statement about omega-3 fatty acids is true?

• A. They have their first double bond at the sixth carbon from the methyl end
• B. Linolenic acid can be converted to EPA and DHA; anti-inflammatory.
• C. They have only single bonds
• D. They cannot be found in fish oils

Answer: (B)

Omega-3 fatty acids are polyunsaturated fats defined by the first double bond occurring three carbons from the methyl end. Alpha-linolenic acid (linolenic acid) is an essential omega-3 that the body can convert, though only to a limited extent, into the longer-chain EPA and DHA. EPA and DHA are associated with anti-inflammatory effects, contributing to the health benefits attributed to omega-3s. That combination—linolenic acid can be converted to EPA and DHA, and these fats have anti-inflammatory activity—is why this statement is true. The other options don’t fit: the first double bond is not at the sixth carbon from the methyl end; omega-3s are not composed of only single bonds but have multiple double bonds; and fish oils are well-known sources of omega-3 fatty acids.