The Root Cause Medicine Podcast

Magnesium is one of those nutrients clinicians think they understand—until they take a closer look. In this episode, we sit down with Dr. Robert Fredrickson, author of Magnesium Answers, to unpack why this foundational mineral continues to create confusion in modern practice. We explore the gap between what standard lab testing shows and what may be happening intracellularly, how lifestyle factors like stress may influence magnesium balance, and how to think more precisely about selecting the right form for the patient in front of you. This conversation is a reminder that advancing patient care isn’t always about adding more complexity—it’s about seeing the fundamentals more clearly.

Clinical Takeaways from This Episode

Why serum magnesium may not reflect total body or intracellular magnesium status
Serum magnesium represents a small fraction of total body stores, which may limit its utility as a standalone marker; intracellular measures like RBC magnesium may offer additional insight (NIH, 2022).

Magnesium’s foundational role in ATP production and metabolic processes.
Magnesium is required as a cofactor in ATP synthesis and numerous enzymatic reactions, supporting energy metabolism and overall cellular function (Gröber et al., 2015).

Magnesium as a cofactor in vitamin D metabolism and nutrient synergy.
Magnesium participates in multiple steps of vitamin D activation, highlighting the importance of evaluating nutrient interactions in clinical planning (Uwitonze & Razzaque, 2018).

Guest Introduction
Dr. Robert Fredrickson is a clinician, educator, and author of Magnesium Answers: Unlocking the Secrets of Magnesium. With a background in sports medicine and functional medicine, he focuses on helping clinicians better understand mineral balance, metabolic health, and evidence-informed supplementation strategies. He also works with Fullscript, supporting providers with clinical decision support and access to professional-grade supplements and nutraceuticals. Dr. Fredrickson also has his own podcast, the Fredrickson Health Show.

FAQ
Is serum magnesium a reliable marker for magnesium status?
Not always. Serum magnesium reflects a small percentage of total body magnesium
Intracellular markers, such as RBC magnesium, may provide additional context
Interpreting trends alongside clinical presentation may support decision-making (NIH, 2022)

What factors may influence magnesium status in patients?
Dietary intake and food quality
Malabsorptive disorders like celiac and IBD
Alcohol intake
Insulin resistance or type 2 diabetes
Vitamin D deficiency (NIH, 2022)

How does magnesium interact with vitamin D?
Magnesium acts as a cofactor in enzymes required for vitamin D metabolism
Inadequate magnesium status may influence how vitamin D is processed in the body (Uwitonze & Razzaque, 2018)

Key Moments (Timestamps)
00:00 – Why magnesium remains overlooked in modern clinical care
02:20 – Dr. Fredrickson’s shift from sports medicine to functional medicine
05:32 – Limitations of serum magnesium testing in clinical practice
07:27 – Understanding intracellular magnesium and RBC testing
09:51 – Magnesium’s role in ATP production and metabolic function
13:25 – Dietary patterns, food quality, and nutrient density challenges
15:55 – How to select the appropriate form of magnesium
18:33 – Magnesium citrate and GI motility considerations, including GLP-1 support
20:46 – Common clinical patterns associated with low magnesium status
22:09 – Safety considerations and when to individualize magnesium use

Sponsor Message
This episode is sponsored by Fullscript, a comprehensive care delivery platform designed to support whole-person, integrative healthcare. Fullscript allows clinicians to streamline supplement dispensing, lab ordering, and patient education in one free, centralized system—helping reduce administrative burden while supporting clinical decision-making. For practitioners, Fullscript offers access to professional-grade supplements, evidence-informed protocols, and lab integrations that can support more efficient planning and follow-up. For patients, it provides a clear, organized way to receive recommendations, manage refills, and stay engaged in their care. The goal is not to replace clinical judgment, but to make it easier for clinicians to focus on what matters most: thoughtful, individualized patient care.

Disclaimer
The views expressed on this podcast are those of the hosts and guests and don’t necessarily reflect those of Fullscript or any affiliated organizations. This podcast is for informational and educational purposes only and is not intended to be medical advice. For your safety, always check with your doctor or healthcare provider before making changes to your health routine.

Citations
Gröber U, Schmidt J, Kisters K. Magnesium in Prevention and Therapy. Nutrients. 2015 Sep 23;7(9):8199-226. doi: 10.3390/nu7095388. PMID: 26404370; PMCID: PMC4586582.
Rosanoff A, Weaver CM, Rude RK. Suboptimal magnesium status in the United States: are the health consequences underestimated? Nutr Rev. 2012 Mar;70(3):153-64. doi: 10.1111/j.1753-4887.2011.00465.x. Epub 2012 Feb 15. PMID: 22364157.
Uwitonze AM, Razzaque MS. Role of Magnesium in Vitamin D Activation and Function. J Am Osteopath Assoc. 2018 Mar 1;118(3):181-189. doi: 10.7556/jaoa.2018.037. PMID: 29480918.
National Institutes of Health. “Magnesium.” National Institutes of Health, 2022, ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/.

What if the real problem with hormones isn’t what’s broken… but what’s being missed?

In this conversation, Dr. Cheryl Burdette invites us to rethink everything we’ve been taught about hormonal health. Instead of chasing isolated lab values or treating systems in silos, she introduces a more useful question: what if hormones only make sense when you look at how they talk to each other?

We explore the concept of the hormonal matrix—a lens that connects thyroid, adrenal, and reproductive hormones into one dynamic, interdependent network. Because in the body, nothing operates alone. Signals overlap. Pathways intersect. And small imbalances can ripple across systems in ways we don’t always measure.

This systems-based perspective isn’t just philosophical—it’s increasingly supported by emerging research on the cross-talk between the HPTA axis, the gut, and broader metabolic and immune signaling. When you zoom out, patterns start to appear. And when you see the pattern, your clinical decisions can change.

This episode is about shifting from fragments to frameworks—and why that shift may open up entirely new possibilities for understanding and supporting hormonal health.

Are your patients putting Salmonella in their morning smoothie? That’s essentially what happened recently when people added what they believed was a safe, antioxidant-packed greens powder to their daily routine. The ingredient? Moringa. Moringa leaf powder is often marketed as a nutrient-dense botanical containing vitamins, minerals, antioxidants, and plant compounds that may support general wellness. For many people, it feels like an easy health habit: add a scoop to a smoothie and start the day feeling proactive about nutrition. But recently, moringa powder was linked to Salmonella infections that resulted in hospitalizations. In this episode, we chat through what clinicians needs to know to keep their clients safe.

A recent analysis of 22 St. John’s Wort supplements purchased online found that only one actually matched its label for the key compound hypericin. Several products contained little to none of the active ingredient, and some appeared to use synthetic dyes to mimic the color of hypericin, potentially misleading simple testing methods (Now, 2025).
Why does this matter? Because when a supplement doesn’t contain the ingredient it claims, patients may not receive the support they expect. That can lead to wasted money, confusing clinical outcomes, and lost trust in integrative care. In this episode of the Root Cause Medicine Podcast, we’re joined by Dr. Eric Viegas, Medical Product Manager at Fullscript, to unpack what this report means for clinicians and patients. We discuss how ingredient discrepancies can happen—from plant sourcing and manufacturing to risks in online marketplaces—and how practitioners can help protect patients from misleading products. We also explore what clinicians should look for when choosing supplements, including validated testing methods, Certificates of Analysis, and quality standards that help ensure products contain what the label promises.

In this episode of the Root Cause Medicine Podcast, we explore a growing clinical reality: patients now have immediate access to advanced bloodwork but not necessarily interpretation with a clinician. In this conversation, we introduce Fullscript Journeys, the provider-led answer to direct-to-consumer lab platforms. With lab testing, AI-supported interpretations and wellness plans, and seamless follow-ups, Journeys empowers providers to deliver a modern patient experience — without compromising clinical guidance.