- 英语听力
- 加入收藏
- 听力课堂 www.TingClass.com 最大的在线英语听力网站，为了下次能再来学习，请牢记本站 www.TingClass.com 的网址
This is the VOA SpecialEnglish Science Report.
The American Heart Association has changed its advice about olderwomen and female hormones. The organization now says healthy orderwomen should not take the hormones to prevent heart disease. And itsays women with heart disease also should not take the hormones. Theassociation says there is growing evidence that the hormones may nothelp and might even cause harm.
Many older women take estrogen and progesterone to replace thehormones that their bodies no longer produce. This is called hormonereplacement therapy. The hormones can ease the physical changestaking place in the body. They strengthen the bones and protectagainst the disease osteoporosis. They also ease feelings of extremeheat that older women sometimes experience.
The hormones also were thought to prevent heart disease in women.The American Heart Association had advised that all women with heartdisease should consider taking estrogen.
Now, however, the Heart Association says women should not takethe hormones to prevent heart attacks and strokes. New research isshowing that the hormones might increase the chances that women withheart disease will suffer these problems.
The Heart Association announced its new decision in itspublication, "Circulation." The decision was based on a four-yearstudy of women with heart disease. In the first year, women takingthe hormones had fifty-two percent more heart-related illnesses thanthose taking an inactive substance. The researchers also found agreater number of women in the hormone group suffered blood clotsand gall bladder disease.
A similar result was seen in a fifteen-year study that involvesmore than twenty-seven-thousand women. After four years, theresearchers found a small increase in the number of heart attacksand strokes among healthy women taking hormones.
About twenty-million women in the United States take hormonereplacement therapy. There has been much debate about whether olderwomen should take the hormones. Research also has shown that takingthe hormones for more than five years can increase some women'schances of developing breast cancer and ovarian cancer.
This VOA Special English Science Report was written by NancySteinbach.