Fatty acid and micronutrient intake and status in association with allergy among pregnant urban women in South Africa
Background: Allergy has become a global problem, consequently reaching epidemic proportions. Worldwide, in both developed and developing countries, the prevalence of allergic disease is rising substantially, with an estimated prevalence of 10−30% of the population being affected. Allergic diseases are a major cause of morbidity. In South Africa, data on the prevalence of allergies in adults are scarce. Dietary intake and nutritional status, particularly of fatty acids and certain micronutrients, may affect allergy in adults. This is of importance in pregnant women, since maternal allergy has been shown to affect the allergic status of their infants. The identification of specific nutrient status and/or intake as modifiable risk factors would be of great value for future prevention and treatment strategies in the mother and her offspring. Aim: To investigate the prevalence of allergy and its association with fatty acid and iron status, as well as zinc and Vitamin E intake, in pregnant urban women in South Africa. Design: This study was nested in the Nutrition during Pregnancy and Early Development (NuPED) study. Within the nested study, associations of maternal dietary intake and nutritional status markers with allergic disease were determined in a cross-sectional manner at <18 weeks of pregnancy. Nutritional status and -intake were compared between the allergic group (n=20) and the non-allergic group (n=82). Results: Based on the ISAAC questionnaire, 19.6% of pregnant women had selfreported allergy symptoms, consisting of a mixture of rhinitis (70% [n = 14/20]), asthma (30% [n = 6/20]), and eczema (15% [n = 3/20]). Gamma linolenic acid (GLA, P=0.021) and arachidonic acid (AA, P=0.044) were lower in allergic women. The dihomo-gammalinolenic acid (DGLA) to GLA ratio was higher (P=0.042) and the AA to GLA ratio(P=0.075) tended to be higher in allergic women. Total PUFA (P=0.068) and n-6 LCPUFA (P=0.062) tended to be lower in allergic women. Allergic women showed a trend to have higher trans-vaccenic acid (VA) levels (P=0.089) and lower n-6 PUFA levels (P=0.084). More allergic than non-allergic women showed a trend to have an n-3 PUFA (P=0.082), n-3 LCPUFA (P=0.082), and AA (P=0.082) status below the median of the total study population. More allergic than non-allergic women had a DGLA to GLA ratio (P=0.019) above the median, and more allergic than non-allergic women tended to have an AA to GLA ratio (P=0.066) above the median. There was no difference between iron status markers or iron deficiency prevalence; vitamin E and zinc dietary intake; or inflammatory markers or inflammation prevalence of the allergic and non-allergic women. Conclusion: Our data showed an allergy prevalence of 19.6%. These pregnant urban women in South Africa with allergy symptoms have lower RBC GLA and AA concentrations, and a higher DGLA to GLA ratio, as compared to their non-allergic counterparts. These altered FA concentrations and ratios suggest a novel mechanism of FA in allergy, indicative of the up-regulation of the FA elongation and possibly desaturation metabolism, with stronger evidence towards elongation. Our study could be extended by investigating lipid mediator concentrations in this population.
- Health Sciences