Isoflavones for Promoting Calcium Absorption and Preventing Bone Loss in Post Menopausal Women

Study Overview
=================
Brief Summary
-----------------
Estrogen is a hormone that helps prevent calcium loss and bone breakdown. During menopause, estrogen levels decrease. Insufficient amounts of estrogen may lead to bone loss and possibly osteoporosis. Isoflavones are natural compounds found in soy plants that may help provide protection against bone loss. This study will evaluate the effect of soy isoflavones on calcium absorption and bone loss in post menopausal women.

Detailed Description
-----------------
Estrogen is a hormone that activates bone-forming cells and prevents calcium loss and bone breakdown. During menopause, estrogen levels decrease. Insufficient amounts of estrogen may accelerate bone breakdown and inhibit the body's ability to create new bone, thereby leading to bone loss and possibly osteoporosis. Various treatments have been developed to decrease bone loss in post-menopausal women. Actonel, for example, is an FDA-approved drug used to help prevent bone loss. Phytoestrogens are plant compounds with a structure similar to estrogen. They have also been shown to help reduce the negative effects of menopause. Isoflavones are a particular type of phytoestrogens that are found in soy plants and may act like estrogen in providing possible protection against bone loss. This study will compare the effects of isoflavones (including genistein, a type of isoflavone) versus Actonel on calcium absorption and bone loss in post-menopausal women. Participants in this double-blind cross-over study will first complete a screening process, which will include answering questions about their health habits, medical history, physical activity, and food patterns. They will then eat one soy bar daily for 3 days. On Day 4, a urine sample will be taken to assess their ability to metabolize phytoestrogen from soybeans. Participants will be randomly assigned to a specific treatment order. Participants will receive 1-4 unique soy isoflavones, followed by Actonel. Treatment phases will be separated by a 50-day washout period. All participants will also take calcium and vitamin D supplements throughout the study. Assessments will include bone density measurements, calcium absorption tests, and blood and urine tests. The study will last approximately 2.5 years.

Official Title
-----------------
Metabolism and Bone Health

Conditions
-----------------
Osteoporosis, Osteopenia

Intervention / Treatment
-----------------
* Dietary Supplement: Genistein vs Risedronate


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: At least 4 years post-menopausal Exclusion Criteria: Not currently taking estrogen replacement therapy or undergoing any treatment for osteoporosis Diagnosis of breast cancer Results of mammogram suggesting breast cancer
Sexes Eligible for Study
-----------------
Female

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Genistein vs. Risedronate<br>Healthy post menopausal women who have been dosed with Ca41. Intervention, 100 mg Gensitein from soy protein isolate for 50 days. After a 50 day washout risedronate (Actonel- 5mg per day) for 50 days | Dietary Supplement: Genistein vs Risedronate<br>* Gensitein (100 gm) from soy protein isolate Risedronate (5 mg)<br>* Other names: Actonel;|
| Active Comparator: Genistein dose and source<br>Healthy post menopausal women will consume 5 products containing varying quantities of genistein from different sources for 50 days each in a randomized order. Each intervention period is separated by a 50 day washout period. Intervention: A) 50 mg genistein from soy protein isolate, B) 100 mg genistein from soy protein isolate, C)50 mg genistein from Novasoy, D) 100 mg genistein from Novasoy, E) 100 ng genistein from 50% Novasoy and 50% soy protein isolate | Dietary Supplement: Genistein vs Risedronate<br>* Gensitein (100 gm) from soy protein isolate Risedronate (5 mg)<br>* Other names: Actonel;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Urinary markers of bone resorption; measured at the end of each treatment phase |  | Every 50 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Serum markers of bone resorption and calcium absorption; measured at the end of each treatment phase |  | Every 50 days | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Bone Resorption, Phytoestrogens, Calcium, Genistein, Equol