If Leptin regulates overall body mass, what factors are responsible for women’s and men’s different body shapes? Classically, women look like pears and men like apples. Women carry more fat ”on” their bodies and deposit most of it in three areas: breasts, hips, and buttocks. Men, on the other hand, carry their fat “within” the body; they tend to accumulate it in the abdominal area and around the intestines. Androgens (the male hormones, one of which is testosterone) also make men’s muscle mass higher and their bodies heavier than women’s.
This sex-specific distribution of body fat is determined importantly by our hormones: the more androgynous a person is, the more he or she is inclined to deposit fat around the midsection. Women with polycystic ovary syndrome (an endocrine problem characterized by infertility, obesity and a male distribution of body hair) have higher levels of androgens than average women and significantly higher waist-hip ratios (the circumference of the hips). Some aspect of hormone balance is genetic. Of all women measured in the European Fat Distribution Study, Mediterranean women had the highest free testosterone concentrations and the greatest abdominal girth.
As any woman who has borne a child can tell you, body shape changes significantly with reproduction. The cause changes in the activity of an enzyme involved in the metabolism of fat (lipoprotein lipase) and in the sensitivity of fat cells to insulin. Body fat is redistributed during pregnancy, when the amount of fat in the upper legs decreases in the third. If the new baby is nursed, the mother accumulates fat in the breasts, upper arms, and upper trunk. By about six months after lactation her body fat distribution returns to baseline levels.
Legato, M.J. (2002) Eve’s Rib The Groundbreaking guide to Women’s Health, Open Road Integrated Media, Inc. Ch. 4 pg. 78
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.”
