Stanford Doctor: Why Active Women & Female Athletes Are Damaging Their Bone Health

To cut through the noise in health and wellness — with honest, research-backed conversations that inspire real people to live longer, stronger, and more fully. No shame, no shortcuts, no wellness theater.

11 May 2026

Bone health for female athletes is one of the most under-discussed topics in women's health, and what you don't know right now could follow you all the way into perimenopause. Dr. Emily Kraus, Sports Medicine Physician and Director of the FASTR (Female Athlete Science and Translational Research) program at Stanford University, joins us to dig into one of the most overlooked areas of women's health: bone density, bone stress injuries, and the hidden epidemic of Relative Energy Deficiency in Sport (RED-S). Dr. Kraus breaks down exactly why female athletes are at disproportionately high risk for bone stress injuries and how under-fueling, even when unintentional, can trigger hormonal suppression, menstrual cycle dysfunction, and long-term skeletal consequences. The conversation spans everything from iron deficiency and foot strike hemolysis to the surprising relationship between estrogen, strength training, and bone building across the lifespan. If you think bone health is only a concern after menopause, this episode will completely reframe how you think about your body at every age. What we explore: - What RED-S is and why it affects far more women than anyone is diagnosing - Why female athletes are at higher risk for stress fractures than male athletes - The silent signs of under-fueling that appear long before you lose your period - Fasted training and young female athletes: why skipping breakfast is not neutral - Iron deficiency in active women: how to test it, which form to take, and why runners are especially vulnerable - Jumping vs. running for bone health, and how to ease into plyometrics safely - How perimenopause accelerates bone loss and what you can actually do about it - Why hormonal contraception can mask RED-S and complicate the clinical picture - Estrogen and bone health: the case for transdermal estrogen in certain athletes - Strength training for bone density: why muscle quality matters just as much as bone density scores - Wearables and the future of early detection for overtrained, under-fueled athletes - Why sleep is a non-negotiable part of bone recovery for athletes at every age About Dr. Emily Kraus: Dr. Emily Kraus is a sports medicine physician and researcher at Stanford University, where she directs the FASTER Program: Female Athlete Science and Translational Research. Her work is focused on closing the gender gap in sport science by producing rigorous research and translating it into real-world clinical tools. She splits her time between treating athletes and leading research on bone health, energy availability, and the female hormone system across the athletic lifespan. She's one of the clearest, most practically minded voices working at the intersection of performance and women's health. Connect with Dr. Emily Kraus: Website: https://fastr.stanford.edu/ (Including practical nutrition and fueling infographics built specifically for female athletes.) Instagram: https://www.instagram.com/stanfordfastr/ | https://www.instagram.com/emilykrausmd/ For a deeper look at the research coming out of FASTR over the past few years: https://drive.google.com/file/d/1QYW2ekv6JGMo4MhoKwnp4SZhg5NtDSIk/view?usp=drive_link Timestamps: 00:00 Intro: Why Women Lose Bone Density Faster Than You Think 03:46 What Is RED-S and Why Most Doctors Miss It 06:01 5 Warning Signs You May Have RED-S Right Now 08:21 Why Fasted Training and Carb Fear Are Wrecking Your Health 11:17 How to Test and Treat Iron Deficiency in Female Athletes 15:12 Why Runners Lose Iron Faster Than Any Other Athlete 17:16 How to Rebuild Bone Density During Perimenopause 20:43 Stop Eating for Leanness Eat for Longevity Instead 25:27 How Birth Control Masks RED-S Symptoms in Athletes 29:54 Estrogen Protects Your Bones: What to Ask Your Doctor 34:38 How Strength Training Builds Bone Density at Any Age 39:03 Why You Cannot Catch Up on Sleep and What to Do Instead – The Proof of Practice: Where Science Meets Practice Hosted by five of the most respected names in women's health: Dr. Abbie Smith-Ryan, Dr. Amber Taylor, Gabby Reece, Dr. Gabrielle Lyon, and Dr. Stacy Sims, this show exists because women have been studied less, treated as afterthoughts, and given advice built for men. We're changing that. Every episode brings evidence-based, experience-backed conversations on strength, metabolism, hormones, longevity, and performance — for women, by women who've dedicated their careers to getting it right. No trends. No shortcuts. Just the proof that practice works. This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit proofpractice.substack.com