Understand Hypothalamic Amenorrhea with Dr. Nicola Sykes (Rinaldi), PhD and Gemma Lewis
You know when someone says, “Oh, that’s normal”, but something in your body clearly doesn’t feel right?
Maybe you’ve lost your period and brushed it off because you exercise a lot. Maybe a doctor waved it away. Maybe you’ve been praised for your discipline, your control, your “healthy” lifestyle, even while your body has been quietly asking for more.
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In this episode, we’re having an honest, deeply human conversation about hypothalamic amenorrhea (HA), disordered eating, and the ways diet culture disguises itself as wellness, especially in athletic, high-achieving bodies.
I’m chatting with both Gemma Lewis & Nicola Rinaldi. Gemma Lewis is a writer and former marathon runner who spent nearly a decade caught up in the culture of "discipline," "clean eating," and relentless training. After losing her period for five years, she was diagnosed with hypothalamic amenorrhea (HA) — a diagnosis that, while medically accurate, allowed both her and her doctors to focus on the symptoms rather than the underlying cause. The HA label obscured what was really happening: an eating disorder fueled by undereating and overtraining. Now recovered, Gemma is passionate about eating disorder awareness and helping others recognize the warning signs that often hide behind athletic achievement and health-focused language. In this episode, she shares her personal story of running, restriction, grief, and losing her period for years.
Dr. Nicola J. Sykes, PhD, is a scientist and author of the groundbreaking book No Period. Now What?, a comprehensive, evidence-based guide to understanding and treating hypothalamic amenorrhea (HA). With a doctoral degree in computational biology from MIT and extensive experience working with people with HA, Dr. Sykes brings both scientific rigor and practical insight to the topic of menstrual health.
Her work has helped thousands of individuals regain menstrual function and loosen the reins of diet culture through lifestyle and nutritional interventions. She has collaborated closely with dietitians, physicians, and mental health professionals to develop effective, client-centered treatment strategies. Drawing on over a decade of research and direct coaching, Dr. Sykes is uniquely qualified to guide individuals and practitioners on the physiology of HA, best practices for recovery, and long-term menstrual health support.
Dr. Nicola Rinaldi shares about the scientific, compassionate breakdown of what’s actually happening in the body when we’re under-fueling, over-exercising, and living in chronic stress.
This isn’t about blame. It’s about understanding. It’s about naming what so many people are experiencing, quietly, often alone, and realizing you’re not broken, weak, or failing. Your body is communicating.
Whether you’re missing your period, questioning your relationship with food and movement, or just feeling exhausted by the constant pressure to do more and eat less, this episode offers clarity, validation, and a powerful reframe: your body isn’t the problem. The system is.
In this episode, we’re talking about…
‘What hypothalamic amenorrhea (HA) actually is and why a missing period is never something to ignore.
Why “exercise more, eat less” culture directly impacts hormones, fertility, and overall health.
How disordered eating can hide behind athleticism, discipline, and “clean” eating.
Gemma’s personal experience of losing her period for years and how grief, running, and control became intertwined.
The common symptoms of HA beyond a missing period including:
Feeling cold all the time
Low libido
GI issues and constipation
Frequent urination
Anxiety, irritability, poor sleep, and exhaustion
Why birth control doesn’t fix HA and how it often masks the underlying issue instead.
The long-term health implications of HA, including bone density loss and hormonal suppression.
Fertility fears vs. reality: what the research and clinical experience actually show.
Why HA can happen at any body size, not just in visibly “thin” bodies.
The role of under-fueling as the most common root cause, even without extreme exercise.
Why recovery often requires weight gain and why that doesn’t mean you’ve failed.
How diet culture makes recovery feel terrifying, even when it’s life-giving.
What actually improves on the other side of recovery: energy, digestion, mental space, connection, joy.
Why community and support matter and why this isn’t something you should navigate alone.
How to start shifting your focus away from body size and toward nourishment, function, and quality of life.
If this episode resonates, there’s a good chance it’s naming something you’ve been living with for a long time. And if that’s the case, you’re not alone, and you’re not imagining it.
Tweetable Quotes
“It is not normal to not have a period.” - Dr. Nicola Rinaldi
“I had prided myself on my body because I thought I was very healthy. What I came to realize was that I was not, and I was abusing my body in a lot of ways.” - Gemma Lewis
“I told countless people in my life that I didn't have my period, and nobody had ever said that. Nobody had ever asked me, ‘Are you not concerned about the long-term implications of this and what you're doing to your body?’” - Gemma Lewis
“Our society really encourages that. Our society encourages exercise more, eat less.” - Dr. Nicola Rinaldi
“I Googled ‘how can I get my period back without gaining weight’. There is no good answer out there.” - Gemma Lewis
“HA can happen to anyone in any body size.” - Dr. Nicola Rinaldi
“You are more than your body.” - Dr. Nicola Rinaldi
Resources
Looking for a speaker for an upcoming event? Let’s chat!
Now accepting new clients! Find out if we're a good fit!
Connect with Dr. Nicola Sykes on Instagram
Related Episodes
Episode 182. PCOS, Eating Disorders, and GLP-1's with Julie Duffy Dillon, MS, RDN, NCC, LDN, CEDS-C
Episode 139. Fertility and Nutrition with Rachelle Mallik
Episode 78. Bone Health and Disordered Eating with Dr. Marci Goolsby
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Hey there! I’m Rachelle, the host of the Understanding Disordered Eating Podcast. As a Licensed Mental Health Counselor, I work with clients to make sense of life’s messy emotional experiences.
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