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

March 30, 2020 updated by: Yale University

Long-term Impact of Protein on Calcium Kinetics

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.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

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.

Study Type

Interventional

Enrollment (Actual)

11

Phase

  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Connecticut
      • New Haven, Connecticut, United States, 06510
        • Yale New Haven Hospital Research Unit

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

20 years to 40 years (Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

Female

Description

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.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: 1
Low protein diet
Other: Low protein diet
Low protein diet for 6.5 weeks

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Calcium absorption and kinetics
Time Frame: Baseline, day 5 and week 6
Baseline, day 5 and week 6

Secondary Outcome Measures

Outcome Measure
Time Frame
Serum Parathyroid hormone
Time Frame: baseline and weekly
baseline and weekly
Markers of bone turnover
Time Frame: baseline and weekly
baseline and weekly

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Yale University

Collaborators

United States Department of Agriculture (USDA)

Investigators

  • Principal Investigator: Karl L Insogna, MD, Yale University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

May 1, 2003

Primary Completion (Actual)

October 1, 2009

Study Completion (Actual)

April 1, 2010

Study Registration Dates

First Submitted

May 1, 2008

First Submitted That Met QC Criteria

May 1, 2008

First Posted (Estimate)

May 5, 2008

Study Record Updates

Last Update Posted (Actual)

March 31, 2020

Last Update Submitted That Met QC Criteria

March 30, 2020

Last Verified

March 1, 2020

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 0304025163

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Subscribe