"ESVITAF". Survey on the vitamin status of the French: relationships between nutrient intake and biochemical indicators.

The relationships between dietary data and biochemical nutritional status for vitamins B1, B2, A, E, beta-carotene, folic acid and iron have been studied using data from a survey conducted on 710 adults. Significant correlations were found between riboflavin intake and biochemical values for males only (r = -0.105, p less than or equal to 0.05), between beta-carotene intake and plasma beta-carotene (r = 0.232, for males and r = 0.292 for females, p less than or equal to 0.001), and between iron intake and plasma iron for males only (r = 0.115, p less than or equal to 0.05). Concerning nutrient densities, correlations were significant between dietary riboflavin and biochemical measure (r = 0.163, p less than or equal to 0.01 for males, r = -0.135, p less than or equal to 0.05 for females), between vitamin A intake (expressed in retinol equivalent) and beta-carotene (r = 0.212, p less than or equal to 0.001 for males, r = 0.157, p less than or equal to 0.01 for females) and for males only, between dietary iron and hemoglobin (r = 0.144, p less than or equal to 0.01). The dietary data for each nutrient were examined for their sensitivity, specificity and predictive values in identifying subjects with substandard or overstandard biochemical values. For all nutrients the positive predictive value percentage was always below 25%, the negative predictive value percentage always under 75%.