Today our guest is Dr. JoAnn Manson, an endocrinologist, epidemiologist, and Principal Investigator of several research studies, including the landmark Women’s Health Initiative. She is a highly cited researcher and was one of the physicians featured in the National Library of Medicine’s exhibition, History of American Women Physicians. Her primary research interests include clinical prevention trials of nutritional and lifestyle factors related to heart disease, diabetes, and cancer and the role of endogenous and exogenous estrogens as determinants of chronic disease. Show notes: [00:02:53] Dawn kicks off the interview by asking JoAnn what it was that drew her to endocrinology. [00:04:33] Ken asks how the things JoAnn witnessed in her early medical practice influenced her interest in disease prevention. [00:05:51] Dawn asks JoAnn to discuss how her mother, who suffered from ovarian cancer, influenced JoAnn’s focus on women’s health. [00:06:40] Dawn asks JoAnn what prompted her interest in clinical research. [00:08:06] Noting the difference between public health and laboratory medical research, Dawn asks JoAnn what the most valuable thing is that she learned from her master’s and Ph.D. work in public health at Harvard. [00:09:10] Ken mentions that while JoAnn and many others are interested in the prevention of disease, our healthcare system does not seem focused on prevention. Ken goes on to asks if this was part of what led JoAnn to work on the Nurses’ Health Study. [00:10:17] Ken asks JoAnn to give an overview of the Nurses’ Health Study for listeners who may not be familiar. [00:11:41] Dawn explains that the Nurses’ Health Study found that women taking hormone therapy had a lower risk of heart disease and a reduction in all-cause mortality. Dawn asks JoAnn to talk about this finding. [00:15:00] Ken asks JoAnn what the impact of the Nurses’ Study has been on public health and women’s health in general. [00:16:29] Dawn asks JoAnn about her experience being a principal investigator in the Women’s Health Initiative starting in 1993. [00:18:17] Ken asks JoAnn to give context regarding how the Women’s Health Initiative (WHI) was designed, how the women were recruited, and what the specific questions were that the study aimed to answer. [00:21:34] Dawn mentions that the three interventions that were evaluated in the WHI were hormone therapy; calcium and vitamin D supplementation; and a low-fat diet. Dawn starts by asking JoAnn about the hormone therapy interventions, and how it was decided which hormone therapies to test. [00:24:25] Dawn asks JoAnn to give some context to the finding from the WHI that women taking the combination of conjugated estrogen and medroxyprogesterone acetate had higher risks of breast cancer and stroke. [00:27:01] Ken asks if the worse outcomes from hormone therapy for older women was due to their advanced age, or the hormone therapy itself. [00:30:25] Ken asks JoAnn to talk about the risk factors for breast cancer that were uncovered by the WHI. [00:35:38] Dawn explains that because of the WHI’s findings, it is more common to use transdermal estradiol, as opposed to the oral form evaluated in the original trial. Dawn asks JoAnn to explain how the different ways these hormone formulations are processed in the body affects the risk benefit ratio. [00:39:04] Dawn asks if these transdermal estradiol treatments might have benefits regarding cognitive decline. [00:43:26] Ken asks JoAnn for her thoughts on the overuse and potential misuse of the term ‘bioidentical hormones.’ Ken goes on to note that the term has seemingly become more related to marketing and further distanced from clinical science. [00:46:48] Dawn asks JoAnn to talk about the role that perimenopausal birth control decisions can play in the management of hot flashes for women in their 40s and 50s. [00:49:14] Ken shifts the conversation to discuss the second pillar of the WHI,