Women’s lungs are smaller than those of men. Before you say “I knew it,” I want to tell you something surprising: the lungs are smaller in women even when we adjust for smaller size of women’s bodies. Furthermore, women have lower levels of hemoglobin, the molecule in the blood that carries oxygen to tissues. Lower hemoglobin levels might seem to require larger lung volume, to compensate for the reduced amount of oxygen circulating through the lungs. But women’s lungs are smaller, not larger and we don’t know why. Oddities like this can only serve as clues to the bigger picture that researchers have pursued for generations.
Long ago pulmonary physiologists figured out a few of the basic gender differences in normal lung function and constructed different tables of normal values for the tests doctors use to measure lung functions. For example, women have less residual volume (the amount of air that remains in the lungs after expelling all the air possible in a single breath) and, predictably, a lower vital capacity (the amount of air that can be moved in and out of the lungs in a breath) than men. More recently researchers have discovered other gender-specific characteristics of the pulmonary system. Progesterone (the hormone that is more abundant after ovulation) stimulates breathing- perhaps an evolutionary adaption to supply any newly fertilized egg with optimally oxygenated blood. Even lung efficiency is enhanced in midcycle, as oxygen and carbon dioxide diffuse more easily between the pulmonary capillaries and the alveolar sacs of the lung. As we discuss the lungs, let’s take a critical look at a few diseases that have disproportionately severe or unusual symptoms in women: lung cancer, chronic obstructive pulmonary disease, asthma, pulmonary hypertension, and sleep apnea.
Legato, M.J. (2002) Eve’s Rib The Groundbreaking guide to Women’s Health, Open Road Integrated Media, Inc. Ch. 11 pg. 211
Marianne J. Legato, MD, Ph. D. (hon. c.), FACP is an internationally renowned academic, physician, author, lecturer, and pioneer in the field of gender-specific medicine. She is a Professor Emerita of Clinical Medicine at Columbia University College of Physicians & Surgeons and an Adjunct Professor of Medicine at Johns Hopkins Medical School. Dr. Legato is also the Director of the Foundation for Gender-Specific Medicine, which she founded in 2006 as a continuation of her work with The Partnership for Gender-Specific Medicine at Columbia University. She received an honorary PhD from the University of Panama in 2015 for her work on the differences between men and women.
At its core, gender-specific medicine is the science of how normal human biology differs between men and women and how the diagnosis and treatment of disease differs as a function of gender. Dr. Legato’s discoveries and those of her colleagues have led to a personalization of medicine that assists doctors worldwide in understanding the difference in normal function of men and women and in their sex-specific experiences of the same diseases.
She began her work in gender-specific medicine by authoring the first book on women and heart disease, The Female Heart: The Truth About Women and Coronary Artery Disease, which won the Blakeslee Award of the American Heart Association in 1992. Because of this research, the cardiovascular community began to include women in clinical trials affirming the fact that the risk factors, symptoms, and treatment of the same disease can be significantly different between the sexes. Convinced that the sex-specific differences in coronary artery disease were not unique, Dr. Legato began a wide-ranging survey of all medical specialties and in 2004, published the first textbook on gender-specific medicine, The Principles of Gender-Specific Medicine. The second edition appeared in 2010 and the third edition, dedicated to explaining how gender impacts biomedical investigation in the genomic era, won the PROSE Award in Clinical Medicine from the Association of American Publishers in 2018. A fourth edition is forthcoming.
She also founded the first scientific journals publishing new studies in the field, The Journal of Gender-Specific Medicine, and a newer version, Gender Medicine, both listed in the Index Medicus of the National Library of Medicine. She has founded a third peer-reviewed, open access journal, Gender and the Genome, which focuses on the impact of biological sex on technology and its effects on human life.
Dr. Legato is the author of multiple works, including: What Women Need to Know (Simon & Schuster, 1997), Eve’s Rib (Harmony Books, 2002), Why Men Never Remember and Women Never Forget (Rodale, 2005), Why Men Die First (Palgrave, 2008), The International Society for Gender Medicine: History and Highlights (Academic Press, 2017), and most recently, The Plasticity of Sex (Academic Press, 2020). Her books have been translated into 28 languages to date.
As an internationally respected authority on gender medicine, Dr. Legato has chaired symposia and made keynote addresses to world congresses in gender-specific medicine in Berlin, Israel, Italy, Japan, Panama, South Korea, Stockholm, and Vienna. In collaboration with the Menarini Foundation, she is co-chairing a symposium on epigenetics, Sex, Gender and Epigenetics: From Molecule to Bedside, to be held in Spring 2021 in Italy. She maintains one of the only gender-specific private practice in New York City, and she has earned recognition as one of the “Top Doctors in New York.”
