| Study summary: |
|
Subjects will be studied 3 or 4 times on the inpatient unit of the Oregon Clinical and
Translational Research Center. During each visit, testing will include measuring the amount
of whole body fat and fat in the stomach area, muscle, and liver; levels of cortisol in the
blood, urine, and fat tissue (taken from a biopsy); how well insulin works (insulin
sensitivity). |
| Criteria: |
|
Inclusion Criteria:
- 40 postmenopausal women (age 40-62) and 30 men (age 18-45) will be recruited if they
are healthy, at their lifetime maximal weight, have been weight stable for at least
six months prior to entry, have a BMI between 19 and 39.9 kg/m2, and be willing to
commit to not making significant changes to their diet or daily activities while
enrolled in the study.
Exclusion Criteria:
- Subjects will be excluded for potential confounders on body weight, cortisol
production rates, sex steroid metabolism, or contraindications to strong magnetic
fields:
1. Age less than 18 to exclude those who might be experiencing alterations in
cortisol production or weight as a result of adolescent growth
2. Subjects who exercise > 30 minutes/day, 3 times a week
3. Smokers
4. Heavy alcohol drinkers (> 2 drinks/ day)
5. Subjects with medical diagnosis including diabetes, heart disease, and cancer
6. Subjects with psychiatric illness (i.e., depression, psychosis, bipolar,
schizophrenia; or are taking medications for these disorders)
7. BMI 40 kg/m2, since obesity influences levels of sex steroids and sex hormone
binding globulin; or body weight > 136 kg (300 lbs), since this is the weight
limit for the DEXA and MR machines
8. Presence of metal in the body such as body piercing, shrapnel, cardiac
pacemakers or aneurysm clips
9. Endocrine diseases affecting body composition, such as untreated hypothyroidism
or Cushing's syndrome, will be excluded by history and physical examination, or
by laboratory evaluation if necessary.
- Women with a contraindication to estrogen use will also be excluded, including: an
estrogen dependent malignancy, active thrombophlebitis, history of deep venous
thrombosis, hypertriglyceridemia, untreated hypertension, cardiovascular disease,
migraine headaches, or current tobacco use.
- Women with frequent hot flashes or disrupted sleep will also be excluded since they
will be unlikely to tolerate randomization to placebo and continued symptoms and
altered sleep cycles will independently affect cortisol secretion patterns.
- All volunteers will have had a normal mammogram within the previous 12 months.
- Any subject with previously unevaluated postmenopausal bleeding will not be included
and, instead, will be referred to a physician for evaluation.
- Women who underwent surgical menopause (bilateral ovariectomy) must be at least one
year out from their surgery before considered eligible so as to allow weight
stabilization after the procedure.
- Men will have had a prostate exam by their primary health provider within the
previous year or by the PI at the time of screening for this study.
- Any subjects taking a blood thinning medication or with an abnormal exam will not be
included and, instead, will be referred to a physician for evaluation |