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Estima warns staying low-carb too long can affect thyroid and menstruation

Diary of a CEO · Women’s Fitness Expert: What You NEED To Know About Dieting & Exercise | Dr. Stephanie Estima · July 20, 2026
Estima warns staying low-carb too long can affect thyroid and menstruation
Diary of a CEO
Diary of a CEO
Women’s Fitness Expert: What You NEED To Know About Dieting & Exercise | Dr. Stephanie Estima
"But if you stay here too long, your thyroid, like so many women >> What's the symptom of the consequence if your thyroid being malfunctioning? >> Yeah, I would say you're always cold. So your hands are cold, you're always cold."
Estima says low-carbohydrate or ketogenic diets can be useful temporarily for some people, including those with type 2 diabetes or PCOS, but argues women can run into problems if they “stay here too long”. Asked about consequences, she lists symptoms she associates with thyroid dysfunction, including feeling cold, heavy menstrual bleeding, and hair shedding.

About this episode

Dr Stephanie Estima, a chiropractor and women’s fitness educator, tells Steven Bartlett she wants to shift women away from pursuing weight loss at “all costs” and towards strength, muscle gain and bone health. She describes her own experience competing in a figure contest, saying she reached 11% body fat, lost her period for months beforehand, later developed hormonal issues and regained the weight, despite receiving praise for her appearance.

Estima outlines four “archetypes” she sees in practice — including “overwhelmed Olivia” and “skinny fat Sophia” — and argues that many women under-eat and avoid heavy resistance training due to fear of bulking. She challenges long-standing gym myths, including spot fat reduction and the idea of a narrow post-workout “anabolic window”.

On diet, she says low-carb or ketogenic approaches may be useful temporarily for certain populations such as people with type 2 diabetes or PCOS, but warns against staying very low-carb long-term, linking it to symptoms she associates with thyroid dysfunction. She also argues that very long fasts can be problematic for women, claiming they can signal “famine conditions” and disrupt menstrual cycling.

Estima discusses sex differences in pelvic anatomy and the implications for squatting mechanics and ACL injury risk, emphasising hip stability. She argues sprinting and jumping should be maintained with age, citing research she says shows sizeable improvements in VO2 max among women in their late 50s. The episode ends with a brief discussion of faith and family legacy.

Key takeaways

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