Steady-state vitamin K sub(2) (menaquinone-7) plasma concentrations after intake of dairy products and soft gel capsules

• Published in: European journal of clinical nutrition Vol. 70; no. 7; pp. 831 - 836
• Main Authors: Knapen, M H J, Braam, L A J L M, Teunissen, K J, van't Hoofd, C M, Zwijsen, R M L, van den Heuvel, E G H M, Vermeer, C
• Format: Journal Article
• Language: English
• Published: 01.07.2016
• ISSN: 0954-3007
• DOI: 10.1038/ejcn.2016.3

Background: In a previous human intervention study, we observed an improved vitamin K status after 8 weeks of intake of a yogurt that was fortified with vitamin K sub(2) (as menaquinone-7, MK-7) and enriched with vitamins C and D sub(3), magnesium and polyunsaturated fatty acids. It was hypothesized that the added nutrients contributed to this improvement. Here we report on a study in which we compared the fasting plasma concentrations of MK-7 from (a) yogurt enriched with MK-7, vitamins D sub(3) and C, magnesium, n-3 poly unsaturated fatty acids (n-3 PUFA) and fish oil (yogurt Kplus), (b) yogurt fortified with MK-7 only (yogurt K) and (c) soft gel capsules containing only MK-7.Subjects/ Methods: For 42 days, healthy men and postmenopausal women between 45 and 65 years of age daily consumed either yogurt K, yogurt Kplus or capsules. Circulating MK-7, 25-hydroxy vitamin D (25(OH)D) and markers for vitamin K status (uncarboxylated osteocalcin (ucOC) and desphospho-uncarboxylated matrix Gla-protein (dp-ucMGP)) were assessed. Plasma MK-7 was also measured during the washout period of 2 weeks. MK-7 and dp-ucMGP were measured in citrated plasma, and 25(OH)D sub(3) and ucOC were measured in the serum. Results: The increase in plasma MK-7 with the yogurt Kplus product was more pronounced than the increase in MK-7 with the capsules. Circulating dp-ucMGP and ucOC were significantly lowered after consumption of the yogurt products and the MK-7 capsules, reflecting vitamin K status improvement. No significant differences in fasting plasma concentrations of various biomarkers between the yogurts were found. Conclusions: Dairy matrix and nutrient composition may affect MK-7 delivery and improvement of vitamin K status. Yogurt fortified with MK-7 is a suitable matrix to improve the nutritional status of the fat-soluble vitamins.