Association between Circulating Osteocalcin and Cardiometabolic Risk Factors following a 4-Week Leafy Green Vitamin K-Rich Diet

Ann Nutr Metab. 2020;76(5):361-367. doi: 10.1159/000511660. Epub 2020 Nov 24.

Abstract

Background: Evidence suggests that lower serum undercarboxylated osteocalcin (ucOC) may be negatively associated with cardiometabolic health. We investigated whether individuals with a suppression of ucOC following an increase in dietary vitamin K1 exhibit a relative worsening of cardiometabolic risk factors.

Materials and methods: Men (n = 20) and women (n = 10) aged 62 ± 10 years participated in a randomized, controlled, crossover study. The primary analysis involved using data obtained from participants following a high vitamin K1 diet (HK; 4-week intervention of increased leafy green vegetable intake). High and low responders were defined based on the median percent reduction (30%) in ucOC following the HK diet. Blood pressure (resting and 24 h), arterial stiffness, plasma glucose, lipid concentrations, and serum OC forms were assessed.

Results: Following the HK diet, ucOC and ucOC/tOC were suppressed more (p < 0.01) in high responders (41 and 29%) versus low responders (12 and 10%). The reduction in ucOC and ucOC/tOC was not associated with changes in blood pressure, arterial stiffness, plasma glucose, or lipid concentrations in the high responders (p > 0.05).

Discussion/conclusion: Suppression of ucOC via consumption of leafy green vegetables has no negative effects on cardiometabolic health, perhaps, in part, because of cross-talk mechanisms.

Keywords: Arterial stiffness; Blood glucose; Blood lipids; Carboxylated osteocalcin; Undercarboxylated osteocalcin; Vitamin K.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Blood Glucose / drug effects
  • Blood Pressure / drug effects
  • Cardiometabolic Risk Factors
  • Cross-Over Studies
  • Diet / methods*
  • Eating / physiology*
  • Female
  • Humans
  • Lipids / blood
  • Male
  • Metabolic Syndrome / prevention & control
  • Middle Aged
  • Osteocalcin / blood*
  • Plant Leaves
  • Vascular Stiffness / drug effects
  • Vegetables*
  • Vitamin K 1 / administration & dosage*

Substances

  • Blood Glucose
  • Lipids
  • Osteocalcin
  • Vitamin K 1