Interrelationship between protein-energy malnutrition and essential fatty acid deficiency in nursing infants.

The influence of severe protein-calorie malnutrition on essential fatty acid (EFA) status was evaluated in nursing infants aged 2-5 mo. A control group of the same age and with normal weight-for-height was also selected for this study. The fatty acid pattern of total phospholipids from plasma and red blood cells (RBCs) was determined and then used as a biochemical variable for evaluating EFA status. A sharp fall in the relative percentage of n-6 (omega-6) fatty acids concomitant with an increase in the n-9 fatty acids in plasma and RBC phospholipids was observed. These results are consistent with the picture of EFA deficiency and showed that the deficiency state is well correlated with the severity of malnutrition. Calculation of the product-precursor ratio of polyunsaturated fatty acids derived from linoleic acid (18:2n-6) in RBC phospholipids provides evidence for an impairment in the elongation-desaturation pathway promoted by the protein-calorie malnutrition.