Patient case (clinical description): A 55-year-old white woman comes for a routine checkup.  She has no significant medical history and does not use tobacco, alcohol, or illicit drugs.  The patient's only medication is an over-the-counter multivitamin.  Family history is notable for a hip fracture in her mother.  Blood pressure is 130/80 mm Hg and pulse is 112/min. She has occasional back pain and lives a sedentary lifestyle with the BMI of 24 Kg/m2. Plain X-ray of the spine shows mild compression fracture at the level of T10. X-ray absorptiometry studies demonstrate abnormally low bone density in the lumbar vertebrae and T-score values below -2.5, which confirms the diagnosis of osteoporosis.

Patient's own account: I'm a 55-year-old white woman and I recently visited my family doctor. I don't smoke anything or drink. I don't have any remarkable medical history. I only use over-the-counter multivitamins to keep myself fresh and energized. My mom had a hip fracture. The doctor took my blood pressure and it was 130/80 and my pulse was 112/min. I have annoying back pain from time to time and to be honest I don't exercise much or move much. My BMI is 24. I did a spine X-ray a while ago and my doctor showed me that I have a fracture on one of my vertebrae. I also have a low bone density in my lumbar vertebrae and T-score values below -2.5. The doctor diagnosed me with osteoporosis.

Clinical trial: Dose-dependent Effects of Vitamin D on Bone Health

Eligibility criteria:
Inclusion Criteria:

          -  Healthy women and men between 55 and 70 years of age; women will be at least 5 years
             post-menopause. Presence of a chronic illness does not exclude participation if the
             condition is stable and managed by a physician.

          -  Baseline lumbar spine and total hip bone mineral density (BMD) T-score above 2.5 as
             assessed using dual x-ray absorptiometry (DXA).

        Exclusion Criteria:

          -  A serum 25-[OH] vitamin D (25OHD) of <30 nmol/L (<12 ng/mL) or >125 nmol/L (50 ng/mL).

          -  Hypercalcemia (serum calcium >2.55 mmol/L), hypocalcemia (serum calcium <2.10 mmol/L)
             or eGFR <30 mL/min.

          -  Surgical cure of Primary Hyperparathyroidism within the last year.

          -  Active kidney stone disease (recurrent stones, recent kidney stone [within last 2
             years])

          -  Known hypersensitivity or allergy to Vitamin D

          -  Serum creatinine, AST, ALT, PTH, calcium, or alkaline phosphatase greater than 1.5
             times the upper limit of normal at the screening visit

          -  BMD exclusions:

               1. High 10-year risk for osteoporotic fracture, as defined by the Canadian
                  Association of Radiologists/Osteoporosis Canada calculator, or the World Health
                  Organization's FRAX calculator.

               2. DXA T-score below or equal to -2.5 SD.

          -  Have taken bone active osteoporosis prescription drugs in the past 2 years
             (bisphosphonates) or 1 year (other osteoporosis prescription therapies).

          -  Any medical condition that would prevent participation in a clinical trial for a full
             three years.

          -  Medications such as prednisone >2.5 mg daily (or equivalent); other bone active
             medications such as tamoxifen or aromatase inhibitors for breast cancer, or androgen
             deprivation therapy of prostate cancer.

          -  Disorders known to affect vitamin D metabolism such as sarcoidosis or renal failure or
             malabsorption disorders (e.g. pancreatic insufficiency or celiac disease).

          -  Regular (monthly or more frequent) use of tanning salons.
No condition on gender to be admitted to the trial.
Accepts Healthy Volunteers
Subject must be at least 55 Years old.
Subject must be at most 70 Years

Eligibility (NLI label): Contradiction