How was WHI conducted?
The WHI study had three components: a randomized clinical trial, an observational study, and a community prevention study. The randomized controlled clinical trial (CT) enrolled 68,132 postmenopausal women between the ages of 50-79. The clinical trial had three study components. If eligible, women could choose to enroll in one, two, or all three of the components. The components were: • Hormone Therapy (HT): This component examined the effect of HT on the prevention of heart disease and osteoporosis, and any associated risk for breast cancer. Women participating in this component took hormone pills or a placebo (inactive pill). • Dietary Modification: The Dietary Modification component evaluated the effect of a low-fat, high fruit, vegetable and grain diet on the prevention of breast and colorectal cancer and heart disease. Study participants followed either their usual eating pattern or a low-fat eating program. • Calcium/Vitamin D: This component started up to 2 years after a woman j
