Beyond MTHFR: When More Isn’t Better in Genetic Health with Rachel Deffendall

About Our Guest

Rachel Deffendall, MSN, APRN, FNP-BC is a board certified family nurse practitioner. In 2023 she founded and opened The Beaumont Med Spa, a specialty clinic with services focusing on bioidentical hormone replacement (BHRT), weight loss and management, IV hydration and vitamin replacement, peptide therapies, genetic testing, hair restoration, facial dermal fillers, botox and customized skin care. The Beaumont Med Spa was recently named Best Med Spa in Wilson County in 2025, Best Med Spa in Middle Tennessee in 2024 by Main Street Awards, and most recently received honorable mention in the Med Spa category for the Guide to Tennessee Best of Tennessee 2025.

Show Notes & Resources

Today, we unpack what methylation really means for our day-to-day health and long-term outcomes. We go beyond the buzz around MTHFR and get into how specific gene variants can shape everything from energy and anxiety to hormone metabolism, miscarriage risk, and cardiovascular disease. Rachel walks us through what happens when we can’t properly convert folate or B12, why homocysteine matters more than most of us realize, and how common interventions (like NAD or GLP-1s with synthetic B12) may backfire if we ignore methylation status. We also explore how genetic testing can guide decisions around estrogen detox, testosterone conversion, and even advanced therapies like ozone and EBOO.

Topics discussed in this episode include:

What methylation means at a biochemical level inside cells.How MTHFR variants C677T and A1298C alter folate metabolism efficiency.Why heterozygous and homozygous mutations create different symptom severity patterns.The connection between folic acid fortification and miscarriage risk.How synthetic folic acid differs from active methylated folate forms.What homocysteine reveals about inflammation and cardiovascular risk.How elevated homocysteine links to early hypertension in younger patients.The role of COMT and CYP genes in estrogen metabolism pathways.Why poor estrogen clearance raises concern for carcinogenic metabolites.How SRD5A influences testosterone conversion into dihydrotestosterone.What genetic data reveals before DHT-related symptoms appear clinically.The risk of using NAD without correcting methylation pathways first.Why cyanocobalamin in GLP-1 formulations may worsen inflammation.The importance of methylated B12 forms for certain genetic profiles.How overmethylation presents with anxiety and mood-related symptoms.The role of EBOO therapy in detoxification and autoimmune support.

The Beaumont Med Spa: https://www.thebeaumontmedspa.com

Rachel on Instagram: https://www.instagram.com/np_deffendall

The Beaumont Med Spa on Instagram: https://www.instagram.com/thebeaumontmedspa

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