Long-term Nutritional Intervention Study to Determine How Protein Affects Calcium Metabolism

NCT ID: NCT00671944

Last Updated: 2020-03-31

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: PHASE1
• Total Enrollment: 11 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2003-05-31
• Study Completion Date: 2010-04-30

Brief Summary

Osteoporosis is a major health problem in men and women in this country and the incidence of this disease is rising. We think that environmental factors such as nutrition may play a role in the increasing prevalence of osteoporosis. In particular, we think that a diet that is too low in protein may be contributing to bone loss. The primary purpose of this study is to compare the long-term impact of a low protein diet on measures of bone and calcium metabolism.

Detailed Description

The protocol is composed of a 9.5-week study, consisting of a 3-week adjustment period followed by a 6.5-week experimental period. During the adjustment period, subjects consume a well-balanced lead-in diet designed to stabilize baseline Ca homeostasis. In the subsequent experimental period, subjects will consume the experimental diet containing 0.7 g protein/kg, 800-1200 mg phosphorus, 800 mg calcium and 2300 mg sodium. During days -6 to -1 of the adjustment diet, 5-10 and days 40-45 of the experimental period, we will measure Ca absorption and kinetics. Weekly assessments of Ca homeostasis will be done using our standard measures of calcitropic hormones, markers of bone turnover, and urine and serum minerals.

Conditions

Osteoporosis

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

1

Low protein diet

Group Type: EXPERIMENTAL

Low protein diet

Intervention Type: OTHER

Low protein diet for 6.5 weeks

Interventions

Low protein diet

Low protein diet for 6.5 weeks

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Healthy Asian or Caucasian women between the ages of 20-40 years.

Exclusion Criteria

• Diseases or medical conditions: gastrointestinal diseases, osteoporosis, diabetes, hypertension, liver disease, thyroid disorders, kidney disease, kidney stones, cancer, heart disease, eating disorders, obesity, hypogonadism , amenorrhea, oligomenorrhea, abnormal serum FSH or estradiol levels, birth control medication, or other hormone-altering medications, pregnancy.
• Lifestyle: smoking, excessive exercise (although moderate exercise is allowed), prescription medications known to influence vitamin D or calcium metabolism or gastric acid, excessive body weight change during the past 6 months, food allergies, unusual eating habits, or medically prescribed diets.
• Also excluded are prisoners and individuals who are cognitively impaired.

• Minimum Eligible Age: 20 Years
• Maximum Eligible Age: 40 Years
• Eligible Sex: FEMALE
• Accepts Healthy Volunteers: Yes

Sponsors

United States Department of Agriculture (USDA)

FED

Sponsor Role: collaborator

Yale University

OTHER

Sponsor Role: lead

Responsible Party

Yale University

Principal Investigators

Karl L Insogna, MD

Role: PRINCIPAL_INVESTIGATOR

Yale University

Locations

Yale New Haven Hospital Research Unit

New Haven, Connecticut, United States

Countries

United States

Other Identifiers

0304025163

Identifier Type: -

Identifier Source: org_study_id