91: You Feel Tired but Labs Look Normal - The Hidden Nitric Oxide Deficiency No One Tests For with Dr. Nathan Bryan
Hormones, Metabolism & You!Show Notes
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What if many hormone, thyroid, and energy problems come down to a single overlooked molecule your body is quietly running out of?
In this episode of Hormones Metabolism in You, Dr. Cassie Smith sits down with nitric oxide expert Dr. Nathan Bryan to explore why nitric oxide is one of the most overlooked yet essential molecules in human health.
Together, they unpack nitric oxide’s powerful role in hormone signaling, thyroid function, gut motility, immune defense, blood flow, and mitochondrial energy production. Dr. Bryan explains how nitric oxide deficiency can contribute to fatigue, hormone resistance, insulin resistance, poor circulation, and chronic inflammation, even when labs appear “normal.”
They also discuss how modern lifestyle factors such as aging, chronic stress, poor diet, fluoride exposure, antiseptic mouthwash use, and long term antacid use can significantly impair nitric oxide production. Most importantly, this conversation offers practical, science backed strategies listeners can apply immediately to support nitric oxide levels and improve overall hormone health, energy, and longevity.
About the Guest
Dr. Nathan Bryan holds a Bachelor of Science in Biochemistry from the University of Texas at Austin and earned his doctoral degree from Louisiana State University School of Medicine in Shreveport, where he received the Dean’s Award for Excellence in Research. He completed postdoctoral training as a Kirschstein Fellow at Boston University School of Medicine in the Whitaker Cardiovascular Institute.
In 2006, Dr. Bryan joined the faculty at the University of Texas Health Science Center at Houston under the recruitment of Nobel Laureate Dr. Ferid Murad. With over two decades of experience in nitric oxide research, he has made significant contributions to the field, resulting in numerous US and international patents and clinically impactful technologies.
Dr. Bryan is also a successful entrepreneur and Founder and CEO of Nitric Oxide Innovations, LLC, where he continues to advance nitric oxide based therapies and molecular medicine worldwide.
Key Topics Covered
What nitric oxide is and why it is essential for human health
How nitric oxide influences hormone signaling and receptor sensitivity
The connection between nitric oxide and thyroid function
Nitric oxide’s role in gut motility, digestion, and the oral microbiome
How nitric oxide supports immune defense and inflammation control
Mitochondrial energy production and cellular oxygen delivery
Why nitric oxide production declines with age
How stress, poor diet, and environmental exposures impair nitric oxide
The impact of fluoride, antiseptic mouthwash, and antacids on nitric oxide production
Common symptoms associated with nitric oxide deficiency
How impaired blood flow affects hormone delivery and tissue response
Links & Resources
Website: https://drnathansbryan.com/LinkedIn: https://www.linkedin.com/in/drnathansbryan
Nitric Oxide Education:https://www.n1o1.com/https://www.no2u.com/https://www.nitricoxideinnovations.com/
Shop N1O1 Products: https://www.awin1.com/cread.php?awinmid=115399&awinaffid=2702698
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