PLASMA CHANGES IN MICRONUTRIENTS FOLLOWING A MULTIVITAMIN AND MINERAL SUPPLEMENT IN HEALTHY ADULTS

Authors: NAVARRO, MIGUEL - HNRCA; WOOD, RICHARD - HNRCA

Submitted to: Journal of the American College of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/5/2002
Publication Date: 1/1/2003
Citation: NAVARRO, M., WOOD, R.J. PLASMA CHANGES IN MICRONUTRIENTS FOLLOWING A MULTIVITAMIN AND MINERAL SUPPLEMENT IN HEALTHY ADULTS. Journal of the American College of Nutrition. (2003) 22:124-32.

Interpretive Summary: Little information exists on the absorbability of nutrients from commercial supplements. We conducted a study to estimate the micronutrient (riboflavin, folate, vitamin C, vitamin B12, iron, zinc and copper) absorbability in healthy adults from a multi-micronutrient dietary supplement to assess the possible influence on it by the tablet disintegration properties and by the relative intestinal permeability of each subject. The absorbability of seven micronutrients from a single brand of multi-micronutrient dietary supplement was measured on two separate occasions in the presence of a standardized test meal in 15 healthy adult subjects, aged 42 ± 14 y. Each subject visited the Metabolic Research Unit on four separate occasions for an absorption test. On one of these visits we assessed intestinal permeability. The other three tests measured the changes in blood micronutrient concentration after consuming a test meal alone (control: placebo effect), or the test meal with either whole or crushed and powdered dietary supplements. We found that the absorbability of riboflavin, folate and vitamin C (whole and crushed tablet), and that for vitamin B12 (only for the crushed tablet treatment) were all significantly higher than after a test meal alone. In contrast, there was no indication that iron, zinc and copper were absorbed in significant amounts from the supplement. Neither the form of the supplement for all micronutrients tested nor intestinal permeability of the subject influenced the absorbability of riboflavin, folate, vitamin C, iron, zinc or copper. In contrast, for vitamin B12 the intestinal permeability of the subject influenced significantly influenced the ability to absorb this micronutrient. We conclude that multi-micronutrients dietary supplements may be a useful vehicle to decrease the prevalence of multiple vitamin deficiencies in healthy adults, but more information on the absorbability of minerals from these supplements is needed.

Technical Abstract: To estimate the micronutrient (riboflavin, folate, vitamin C, vitamin B12, iron, zinc and copper) bioavailability in healthy adults from a multi-micronutrient dietary supplement to assess the possible influence on it by the tablet disintegration properties and by the relative intestinal permeability of subject. The bioavailability of seven micronutrients from a single brand of multi-micronutrient dietary supplement was measured on two separate occasions in the presence of a standardized test meal in 15 healthy adult subjects. Each subject visited the Metabolic Research Unit on four separate occasions for an absorption test. One test measured the intestinal permeability. The other three tests measured the postprandial changes in plasma or serum concentrations after consuming a test meal alone (control: placebo effect), or the test meal with either whole or crushed and powdered dietary supplements. 15 healthy Caucasian adult volunteers, aged 42 ± 14 y. The 12h-post-dose AUC for riboflavin, folate and vitamin C (whole and crushed tablet), and that for vitamin B12 (only for the crushed tablet treatment) were all significantly (p < 0.001) higher than after a test meal alone. In contrast there was no significant increase in the AUC after supplement intake for iron, zinc and copper. Neither the form of the supplement for all micronutrients tested nor intestinal permeability of the subject for riboflavin, folate, vitamin C, iron, zinc and copper influenced the post dose nutrient AUC. In contrast, for vitamin B12 the intestinal permeability of the subject influenced significantly the nutrient AUC (p = 0.003). Tablet disintegration characteristics of this dietary supplement did not limit absorption of these seven micronutrients. The intestinal permeability of subject was only positively correlated with the B12 bioavailability. Results are suggestive of using multi-micronutrients dietary supplements as a vehicle to decrease the prevalence of multiple micronutrient deficiencies overall for vitamins in healthy adults.