Tinoco Sandra Manzato Barboza, Sichieri Rosely, Setta Cecília Leal, Moura Anibal Sanchez, do Carmo Maria das Graças Tavares
Departamento de Ciências Fisiológicas/Laboratório de Fisiologia Celular, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil.
J Paediatr Child Health. 2008 Jan;44(1-2):50-6. doi: 10.1111/j.1440-1754.2007.01172.x. Epub 2007 Jul 19.
The presence of trans fatty acids (TFA) in human milk may be a concern because of their possible adverse nutritional effects on the infant development. TFA may interfere with the metabolism of long-chain polyunsaturated fatty acids (LC-PUFA). Marked variation in TFA of milk appears in different populations. No data have yet been reported in Brazil, particularly as regards the milk of mothers of premature infants. Because of the importance of LC-PUFA in infant growth and development, we investigated the fatty acids composition of the milk of Brazilian mothers of premature infants.
We analysed, through gas-liquid chromatography, the content of fatty acids of 37 milk samples obtained from mothers delivering prematurely. Samples were collected from colostrum and mature milk of exclusive breastfeeding.
All samples contained trans isomers of C18:1 acid with trans isomers of PUFA in lower proportion. The percentage of TFA (mean +/- SD) in the colostrum was 2.34 +/- 0.75, and 2.19 +/- 0.47 in the mature milk. For the LC-PUFA these values were 0.97 +/- 0.34 in the colostrum and 0.66 +/- 0.25 in the mature milk. The contents of total essential fatty acids and PUFA n-6 were inversely correlated with TFA in colostrum and mature milk. We found a positive correlation between levels of arachidonic acid in mature milk and change in the children's height.
The study showed that the intake of TFA occupies an intermediate position between the values of North America and European countries, reflecting the ongoing transition to industrialised foods in Brazil.
母乳中反式脂肪酸（TFA）的存在可能令人担忧，因为它们可能对婴儿发育产生不良营养影响。TFA可能会干扰长链多不饱和脂肪酸（LC-PUFA）的代谢。不同人群的母乳中TFA存在显著差异。巴西尚未有相关数据报道，尤其是关于早产儿母亲的母乳。由于LC-PUFA在婴儿生长发育中的重要性，我们调查了巴西早产儿母亲母乳中的脂肪酸组成。
我们通过气液色谱法分析了37份早产母亲的母乳样本中的脂肪酸含量。样本取自纯母乳喂养的初乳和成熟乳。
所有样本均含有C18:1酸的反式异构体，多不饱和脂肪酸（PUFA）的反式异构体比例较低。初乳中TFA的百分比（均值±标准差）为2.34±0.75，成熟乳中为2.19±0.47。对于LC-PUFA，初乳中的这些值为0.97±0.34，成熟乳中为0.66±0.25。初乳和成熟乳中总必需脂肪酸和PUFA n-6的含量与TFA呈负相关。我们发现成熟乳中花生四烯酸水平与儿童身高变化呈正相关。
该研究表明，TFA的摄入量处于北美和欧洲国家之间的中间位置，反映了巴西向工业化食品的持续转变。
