Research

Macro partitioning

Increasing dietary EPA and DHA intake significantly reduces the metabolic conversion of alpha-linolenic acid (ALNA) to EPA and DPA in older men, demonstrating feedback inhibition of the desaturation/elongation pathway.

If you consume both plant-based omega-3s (ALNA) and fish oil (EPA/DHA), be aware that the fish oil will suppress your body's ability to convert the plant fats into long-chain omega-3s. Since the conversion rate is already very low, this suppression is likely negligible for your overall EPA/DHA levels, but it confirms that plant fats are not an efficient source of long-chain omega-3s when pre-formed sources are available.

ModerateSupportsMEDIUM confidence
increased consumption of EPAþDHA significantly reduced (P<0.05) cumulative concentrations of [13C]EPA (2-fold) and [13C]DPA (4-fold) in plasma PC relative to baseline.
Graham C. Burdge et al. · British Journal Of Nutrition · 2003

Why this rating

Small sample size (n=5 for this group), but clear statistical significance (P<0.05) and consistent with tracer data.

Source

Effect of altered dietary<i>n</i>-3 fatty acid intake upon plasma lipid fatty acid composition, conversion of [<sup>13</sup>C]α-linolenic acid to longer-chain fatty acids and partitioning towards β-oxidation in older men

Graham C. Burdge et al. · British Journal Of Nutrition · 2003

DOI 10.1079/bjn2003901

rct · n=14Cited 228×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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