Alpha linolenic acid in cholesterol esters: a marker of alphalinolenic acid intake in newborns

Abstract

Objective: To evaluate α-linolenic acid (ALA) (18∶3 n-3) and linolenic acid (LA) (18∶2 n-6) in cholesterol esters (CE) as markers of ALA and LA dietary intakes in preterm infants.

Subjects: Forty-five preterm infants: two groups fed different formulas, the third fed human milk.

Design: ALA and LA dietary intakes were precisely recorded in each infant to accurately determine the cumulative amount of ingested ALA and LA during two intervals: (i) between the second day after the first significant formula intake (D0) and the fifteenth day (D15); and (ii) between D0 and the first day of the 37th week of post-conception age (W37). The corresponding amounts of ingested ALA and LA were related to ALA and LA levels determined by capillary column gas–liquid chromatography in plasma cholesterol esters at D15 and W37, respectively.

Results: ALA in CE was very significantly correlated to D0–D15 and D0–W37 ALA intakes (0.66; P=0.0001 and 0.70; P=0.0001), respectively. LA in CE was weakly correlated to D0–D15 LA intakes (0.03; P=0.01) and whatever the group (human milk or enriched formula) the correlation was lost at W37.

Conclusion: In preterm infants, ALA in CE can be considered as representative of ALA dietary intakes, whereas LA in CE appears as a poor marker of LA intakes.

European Journal of Clinical Nutrition (2000) 54, 840–843