Abstract :Body concentrations of Arachidonic Acid (AA, 20:4 n6) and Eicosapentaenoic Acid (EPA, 20:5 n 3) are influenced by diet. Previously, we reported that the concentration range of AA and EPA might explain that %AA and %EPA are positively associated, and that variability of OA (18:1 c9) influences this association. We now investigate whether also the range of ALA (18:3 n3) might influence the association between %AA and %EPA, using data from a diet trial in chickens. A broadening (narrowing) of ALA-variability made the %AA vs. %EPA scatterplot improve (be poorer), as observed both when calculating percentages of all fatty acids, and when using ALA, AA, and EPA only in the denominator.
Thus, the positive association between relative amounts of AA and EPA in breast muscle lipids of chickens is influenced by ALA variability. We raise the question of whether differences in concentration ranges between the many types of fatty acids (possibly acting via skewness) might serve as an evolutionary mechanism to ensure that percentages of fatty acids will be positively or negatively associated: a Distribution Dependent Regulation.