Physiological serum 25-hydroxyvitamin D concentrations are associated with improved thyroid function-observations from a community-based program.

Purpose: Vitamin D deficiency has been associated with an increased risk of hypothyroidism and autoimmune thyroid disease. Our aim was to investigate the influence of vitamin D supplementation on thyroid function and anti-thyroid antibody levels.

Methods: We constructed a database that included 11,017 participants in a health and wellness program that provided vitamin D supplementation to target physiological serum 25-hydroxyvitmain D [25(OH)D] concentrations (>100 nmol/L).

The importance of dose, frequency and duration of vitamin D supplementation for plasma 25-hydroxyvitamin D.

The importance of dose, frequency and duration of vitamin D supplementation for plasma 25(OH)D levels is not well described and rarely reported for supplementation that exceeds 2000 IU per day. The objective is to examine dose, frequency and duration of supplementation in relation to plasma 25(OH)D in a large population-based sample. We accessed data on 2714 volunteers that contributed to 4224 visits and applied multilevel regression.

The association between amalgam dental surfaces and urinary mercury levels in a sample of Albertans, a prevalence study.

Objective: The objective of this study was to quantify the relationship between number of dental amalgam surfaces and urinary mercury levels.

Methods: This study uses participant data from a large philanthropic chronic disease prevention program in Calgary, Alberta, Canada. Urine samples were analysed for mercury levels (measured in μg/g-creatinine).

A novel approach localizes the association of vitamin D status with insulin resistance to one region of the 25-hydroxyvitamin D continuum.

Vitamin D status has been implicated in insulin resistance, type 2 diabetes mellitus, and hypertension, but the range of vitamin D status values over which the association can be found is unknown. Our objective was to define this range in a cohort of nondiabetic adult Canadians. We used a regression modeling strategy, first adjusting insulin-response variables and systolic and diastolic blood pressure for BMI, waist circumference, weight, age, and sex.