Folate status of adults living in the Canary Islands (Spain)

Human studies support the hypothesized contribution of folate deficiency to carcinogenesis and vascular risk. We assess the nutritional folate status and its relationship to folate intake, smoking, alcohol consumption, oral contraceptive use, and multivitamin supplements.

A representative sample of 601 individuals from 18 to 75 years of age was selected from the participants in the Canary Islands Nutrition Survey. A food frequency questionnaire was administered. Serum and erythrocyte levels of folate were determined using a method of automated ionic capturing.

Mean serum and red cell folate were 8.2 ng/mL and 214.3 ng/mL, respectively. Only one individual had serum folate below 3 ng/mL, and 21.7% showed moderate deficits (3-6 ng/mL); 10.7% of the sample had erythrocyte folate levels falling below 140 ng/mL, 61.3% between 140 and 240 ng/mL and the remaining 27.9% above 240 ng/mL. A positive significant association was observed between these two folate measurements, as well as between folate intake and each of these biomarkers (p < 0.001). Tobacco consumption was negatively correlated with folate status (p < 0.001). Alcohol consumption, oral contraceptive, and vitamin supplement use were not associated with serum and red cell folate levels.

Even though nutritional folate status can be considered minimally acceptable, it may reflect the low level of fruit and vegetable consumption within the Canary Islands population.