After menopause, the ovaries stop making the hormones estrogen and progesterone. For some women, the decrease in hormone levels causes hot flashes and other uncomfortable symptoms. Postmenopausal hormone therapy consists of taking estrogen with or without progesterone to reduce the uncomfortable symptoms of menopause. A recent study showed that postmenopausal hormone therapy also reduces colorectal cancer and osteoporosis but increases heart attack, stroke, and breast cancer. Ongoing studies are examining other risks and benefits of hormone therapy. Some previous studies suggest that women taking hormone replacement therapy have better blood sugar levels than women not taking it. Blood sugar is important in postmenopausal women because of its relationship to type 2 diabetes. Type 2 diabetes is a common disease that interferes with the body's ability to use and store energy from food and leads to high blood sugar levels. Over time, high blood sugar levels can lead to blindness, kidney failure, nerve damage, and possibly heart disease.