Effect of Blueberries on Bone Turnover

Purdue University

Status and phase: Unknown; Phase 2; Phase 1

Conditions: Bone Loss, Age-related; Osteoporosis, Postmenopausal

Treatments: Dietary Supplement: Blueberry Baseline; Dietary Supplement: Blueberry Low; Dietary Supplement: Blueberry Medium; Dietary Supplement: Blueberry High

Study type: Interventional

Funder types: Other

Identifiers

NCT02630797

BB2015

Details and patient eligibility

About

This study uses a bone labeling calcium tracer methodology to compare the dose-response effect of blueberry consumption on calcium retention and bone loss. Post-menopausal women will receive food or beverage products containing freeze-dried blueberries in the amount equivalent to 0.75 (low), 1.5 (medium), and 3 cups (high) of fresh blueberries per day over a 42-day period. The hypothesis is that the polyphenolics found in blueberries will reduce calcium loss from bones.

Full description

Participants will be dosed with Ca-41, a rare long-lived radioisotope of calcium. After the equilibration of tracer in the body and its deposition in bones (150 days), subjects will be randomized to one of 6 dose sequences, all of which will begin with a 42-day baseline period. During baseline, 24-hour urine will be collected every 14 days. Following baseline, subjects will enter a 42-day intervention period with one of three doses of blueberries equivalent to 0.75 (low), 1.5 (medium), and 3 cups (high) of blueberries per day. Each dose will be provided in the form of freeze-dried blueberry powder incorporated in 2-4 foods or beverages per day. During the intervention, 24-hour urine will be collected weekly for 6 weeks except week 1. After intervention, subjects will enter a 42-day washout period, during which 24-hour urine will be collected every 3 weeks. The entire study duration will be 444 days for subjects who have not been dosed with Ca-41 previously. In a crossover design, all subjects will complete three 42-day intervention periods corresponding to the three doses of blueberries (low, medium, and high), each followed by a 42-day washout period. The dose-response effect of continuous blueberry consumption over a 42-day period on bone resorption in healthy post-menopausal women will be studied by measuring the loss of Ca-41 in urine by Accelerator Mass Spectrometry.

Enrollment: 20 patients

Sex: Female

Ages: 45 to 70 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Female subject is healthy
• Subject is > 4 years past the onset of natural menopause or total hysterectomy

Exclusion criteria

• History of metabolic bone disease or low trauma fractures;
• Subject taking osteoporosis treatment drugs or glucocorticoids within 6 months of the beginning of the study;
• Subjects taking bisphosphonates within 2 years of the beginning of the study;
• History of cancer, thromboembolisms, clotting disorders, uncontrolled hypertension, abnormal thyroid function, malabsorption syndrome, seizure disorders, or heart attack;
• BMI > 35 kg/m2;
• Subjects who will not comply with study interventions ;
• Subjects who will not stop taking natural product supplements of their own selection.

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Single Blind

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20 participants in 4 patient groups, including a placebo group

Blueberry baseline

Placebo Comparator group

Description:

No blueberry products provided as part of the usual dietary intake

Treatment:

Dietary Supplement: Blueberry Baseline

Blueberry Low

Active Comparator group

Description:

One blueberry product per day containing an equivalent of 0.75 cups of fresh blueberries provided as part of usual dietary intake for 42 days

Treatment:

Dietary Supplement: Blueberry Low

Blueberry Medium

Active Comparator group

Description:

Two blueberry products per day containing an equivalent of 1.5 cups of fresh blueberries provided as part of usual dietary intake for 42 days

Treatment:

Dietary Supplement: Blueberry Medium

Blueberry High

Active Comparator group

Description:

Four blueberry products per day containing an equivalent of 3 cups of fresh blueberries provided as part of usual dietary intake for 42 days

Treatment:

Dietary Supplement: Blueberry High