Essential Fatty Acids

Essential Fatty Acids (EFAs) are fatty acids that cannot be synthesized by the human body and must be obtained from the diet.

Examples:

  • Linoleic acid (Omega-6) – C18:2 (Δ9,12)

  • Alpha-linolenic acid (Omega-3) – C18:3 (Δ9,12,15)
    (Arachidonic acid becomes essential if linoleic acid is deficient.)

Functions:

  • Structural component of cell membranes.

  • Precursors for eicosanoids (prostaglandins, thromboxanes, leukotrienes).

  • Important for growth, brain function, skin health.

Daily requirement: ~3% of total energy intake.

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