None listed
Conditions
Brief summary
Calcium supplements have been associated with increased cardiovascular risk, which might be related to their acute effects on serum calcium. This study aims to compare the effects on serum calcium of 0.5 g of calcium as citrate fasting, as citrate after a protein and fat rich meal, from unfortified dairy products or from calcium-fortified juice.
Interventions
A single dose of each of the following three treatments after fasting for at least 8 hours: 0.5 g of calcium as citrate (oral tablet) after a meal containing protein and fat, 0.5 g of calcium from unfortified dairy products (milk, yoghurt and cheese) or 0.5 g of calcium from a calcium-fortified fruit juice. Each dose will be separated by at least 7 days.
Sponsors
University of Auckland
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Prevention
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
0 to No maximum
Healthy volunteers
Yes
Inclusion criteria
Female, postmenopausal 5 years or more (menopause defined as at least 12 months since last period in a woman aged > 45 yrs with intact uterus, or serum oestradiol < 100 pmol/l with FSH > 50 IU/l in younger or hysterectomised woman).
Exclusion criteria
Renal impairment (serum creatinine >0.15 mmol/L), chronic liver disease, untreated hypothyroidism or hyperthyroidism, concurrent major systemic illness (including malignancy), active major gastrointestinal disease, metabolic bone diseases, or serum ALP >normal, primary hyperparathyroidism, current or expected use of oral glucocorticoid drugs during the trial period, current or past use of bisphosphonate therapy in the preceding 2 years, use of hormone replacement therapy within the last 12 months, use of other medication known to cause osteoporosis or interfere with bone metabolism.
Outcome results
None listed