Do egg yolks and processed meats supply arachidonic acid?

Egg yolk and certain processed meats contain preformed arachidonic acid (AA), and human intervention studies show that ingested AA is incorporated into circulating lipid compartments. This supports the claim, while emphasizing that food-specific content and tissue distribution vary.

Dietary sources

• Egg yolk is a robust source. GC/GC–MS analyses measured about 6.32–8.11 mg AA/g fresh yolk (632–811 mg/100 g) in one study. Absolute values vary with hen diet, age, housing, and whether results are reported by fresh weight, dry matter, or total fatty acids.
• Processed meat can supply AA, but this is product-dependent. Dry fermented sausages contained 0.45–0.82 g AA/100 g total fatty acids by GC analysis; this cannot be converted to an amount per 100 g of sausage without its total fat content. Liver sausage has also been identified as containing AA. These findings should not be extrapolated to every processed-meat product or brand.

Human incorporation and mechanism

• In randomized trials, 240 or 720 mg/day for 4 weeks increased plasma-phospholipid AA dose-dependently, with levels moving back toward baseline after washout. A separate 1.5 g/day, 4-week trial likewise increased plasma AA.
• A systematic review of 14 randomized trials, using 80–2,000 mg/day (usually short-term), found increased AA in plasma lipid fractions and erythrocytes. This indicates that dietary preformed AA enters membrane-associated circulating lipid pools and contributes to their availability.

Scope of the finding

• The clearest evidence concerns plasma phospholipids and erythrocytes. An adipose-tissue study found no AA increase, so blood incorporation should not be assumed to represent uniform accumulation across all tissues.
• Effects on EPA or the AA:EPA ratio are inconsistent: EPA declined in some studies but was unchanged in others.

Bottom line

• Egg yolk and selected processed meats can provide AA, and dietary AA reliably raises AA in circulating phospholipid and erythrocyte pools in short-term human trials. Egg yolk evidence is especially strong; processed-meat AA content is highly formulation-specific.