Stability and effect of ingestion on folate levels in plasma

Abstract

The physiological demand of folates increases during adolescence, pregnancy and lactation due to the rapid growth and anabolic activity during these stages of life. The periconceptional deficiency of folates is a risk for the presence of neural tube defects. We studied the stability of folates concentration in plasma and the effect of ingestion of a breakfast rich in folates on the postprandial levels of this micronutrient, up to two hours after food intake. For the stability assay the samples were stored protected from light at -70 °C and analysed at time intervals of 1, 8, 30, 90 and 120 days. The mean folates concentration in plasma was higher in postprandial stage (8.9 ng/dl) that in fasting (7.9 ng/dl), which represents a statistically significant (p<0.01) increase of 11%. This study confirms that fasting is important in folates determination for diagnosis and reasearch purposes to establish deficiency prevalence of this micronutrient in a population. Concerning the stability of folates concentration, we did not find a significant difference between the several time analysis (p>0.1); this suggests that folates concentrations in plasma remain stable under the experimental conditions described.