How Menopausal Estrogen (Bioidentical or Synthetic) May Fuel Hypothyroidism & Weight Gain and How Functional Medicine Can Help
Featuring Dr. Shannon O’Keefe’s work in root-cause hormone balance
Introduction
Menopause marks a major hormonal transition for women, often accompanied by symptoms like hot flashes, mood shifts, sleep disturbances, and changes in metabolism. Many women are prescribed estrogen (bioidentical or synthetic) to manage menopausal symptoms. But what many do not realize is how hormone replacement can interact with thyroid function and in some cases contribute to hypothyroid symptoms and stubborn weight gain.
In this post, we will explore:
-
The differences between bioidentical and synthetic estrogen
-
Mechanisms by which estrogen influences thyroid function
-
Why some menopausal women on estrogen develop low thyroid symptoms or weight gain
-
How a functional medicine lens as practiced by Dr. Shannon O’Keefe can help unravel and resolve these overlapping hormonal challenges
Bioidentical vs Synthetic Estrogen: What’s the Difference?
-
Bioidentical estrogen refers to hormones whose molecular structure is identical to what the human body produces. Some forms are FDA-approved and others are compounded formulations tailored by practitioners.
Link: https://my.clevelandclinic.org/health/treatments/15660-bioidentical-hormone - Synthetic estrogen refers to hormones whose molecular structure is similar but not identical to natural estrogen.
Link: https://www.npoptimalhealth.com/blog/bioidentical-vs-synthetic-hormones - Risks and misconceptions:
Link: https://www.mayoclinic.org/diseases-conditions/menopause/expert-answers/bioidentical-hormones/faq-20058460
The Estrogen and Thyroid Connection: How Estrogen Can Push You Toward Hypothyroid
-
Increased Thyroxine Binding Globulin (TBG)
Link: https://pmc.ncbi.nlm.nih.gov/articles/PMC3113168/ - Effects on Thyroid Autoimmunity and Estrogen Metabolites
Link: https://www.rupahealth.com/post/the-estrogen-thyroid-connection-and-its-impact-on-womens-health - Slowed Estrogen Clearance When Thyroid Is Low
Link: https://www.rupahealth.com/post/the-estrogen-thyroid-connection-and-its-impact-on-womens-health
Why Weight Gain Often Follows
Estrogen and thyroid imbalance can lead to:
-
Lower basal metabolic rate
-
Water retention and bloating
-
Adipose fat redistribution
-
Insulin and leptin resistance
-
Appetite and satiety disruption
This explains why weight gain in menopause is not always “just aging.”
Putting It Into Context: Bioidentical vs Synthetic and Thyroid Risk
-
Oral estrogen tends to increase TBG (Thyroxine-Binding Globulin) more than transdermal
-
Transdermal (patch or gel) may have fewer thyroid-binding effects
-
Bioidentical vs synthetic: data are not definitive, both can still impact thyroid function
-
“Safer” does not equal “harmless” and monitoring is essential
Why Choose Functional Medicine and Natural Options
When it comes to hormone balance, there is no one-size-fits-all solution. Standard approaches often focus only on lab numbers or a prescription, but many women still feel unheard and unsupported. A functional medicine practitioner looks at the bigger picture — not just your hormones, but also your thyroid, adrenals, digestion, liver detoxification, stress response, and nutrition. This whole-body perspective is what helps uncover the true causes of your symptoms.
Many women also prefer bioidentical hormones because they are structurally identical to the estrogen your body naturally produces. While both bioidentical and synthetic hormones can influence thyroid function, bioidentical hormones are generally better tolerated and may support a more natural rhythm in the body. With functional medicine, the goal is not to overload you with medication but to help your body find balance using the gentlest and most natural methods possible.
Meet Dr. Shannon O’Keefe: A Functional Medicine Partner for Women in Midlife
Dr. Shannon O’Keefe has built her career around helping women feel like themselves again when hormones, thyroid health, and metabolism feel out of balance. She is not only a Doctor of Chiropractic and a Diplomate in Clinical Nutrition (DCBCN) but also someone who listens closely, digs deeper, and looks for the root causes behind your symptoms.
At her clinic in Saint Paul, O’Keefe Matz Functional Health, Dr. O’Keefe blends science-based testing with a personalized, caring approach. Patients often say that what makes her different is the way she takes the time to connect the dots and explain what is really going on in their body. Whether it is sorting out the tricky relationship between estrogen and thyroid, creating nutrition strategies that work in real life, or fine-tuning a care plan as your body changes, her goal is always the same: to help you feel energetic, balanced, and back in charge of your health.
Learn more about Dr. Shannon O’Keefe:
https://improveurhealth.com/users/dr-shannon-a-okeefe
Clinic website:
https://improveurhealth.com
