Explore Dr. Retzler’s HormoneSynergy® Longevity Medicine Resource Library

Longevity Medicine, Functional Wellness & Anti-Aging Insights from HormoneSynergy®

Welcome to the HormoneSynergy® Longevity Medicine Blog, a physician-guided clinical library led by Dr. Kathryn Retzler. Our articles cover the systems that most often shape health with age: metabolic health, hormones, cardiovascular and kidney risk, body composition, bone and muscle, brain health, sleep, gut health, nutrition, supplements, and the biology of aging.

The library is organized around clinical questions rather than trends. Some articles review new research. Others explain testing, treatment, nutrition, or a condition patients commonly encounter. Across the collection, the standard is the same: evidence first, appropriate uncertainty, and enough clinical context to separate useful medicine from wellness marketing.

Start with the HormoneSynergy® Longevity Medicine Framework

New & recently updated:

Metabolic Health & Insulin Resistance

Clinical resources on insulin resistance, glucose regulation, metabolic syndrome, visceral fat, prediabetes, obesity and GLP-1-based care within a broader longevity medicine plan.

Kidney Health & Cardiovascular-Kidney-Metabolic Health

Kidney health belongs in the same clinical conversation as blood pressure, diabetes, insulin resistance, obesity and cardiovascular risk. These resources cover early detection, CKD, albuminuria, nutrition and CKM health.

Gut Health, Microbiome & Immune Signaling

Clinical education on the microbiome, intestinal barrier, fiber, inflammation, gut-brain signaling, immune biology and the growing connections between gut, metabolic and kidney health.

Food Quality, Vitamins, Supplements & Wellness Claims

Evidence-based guidance on nutrient gaps, supplement quality, interactions, food claims and longevity products, with an emphasis on where supplementation helps and where marketing outruns the evidence.

  • Cholest Protect for Cholesterol, ApoB, and Cardiometabolic Support

    Cholest Protect for Cholesterol, ApoB, and Cardiometabolic Support

    Cholest Protect is a physician-formulated blend of Bergamonte® citrus bergamot, berberine, and Curcumin C3 Complex® designed to support healthy cholesterol metabolism, lipid balance, ApoB-aware cardiometabolic care, and long-term vascular wellness as part of a broader longevity medicine strategy.

  • The Three Centers: Body, Heart, and Head in Longevity

    Enneagram Three Centers image showing Body, Heart, and Head patterns in health behavior change and sustainable longevity in the HormoneSynergy approach.

    The Enneagram is often grouped into three centers of intelligence: Body, Heart, and Head. Each center brings a different way of sensing the world, reacting to stress, and approaching health change. In longevity work, understanding the centers can help us see whether we lead with instinct, image and emotion, or thought and security — and what each center may need for sustainable health.

  • ALT and Fatty Liver: An Early Metabolic Signal

    ALT clinical illustration showing liver stress, fatty liver patterns, and early metabolic dysfunction relationship

    ALT is a liver enzyme that can help signal early metabolic dysfunction, especially when it rises alongside insulin resistance, visceral fat, and fatty liver patterns. Even mild elevation may matter in the right clinical context.

  • HDL Cholesterol and Longevity

    HDL cholesterol clinical illustration showing lipid transport and relationship to metabolic and cardiovascular health

    HDL cholesterol is often referred to as “good cholesterol,” but its role is more complex. It helps transport cholesterol and reflects aspects of metabolic and cardiovascular health, especially when interpreted alongside triglycerides and insulin resistance.

  • Tri-Fortify® Liposomal Glutathione: Dr. Retzler’s Pick When You Prefer Liposomal Over Capsules

    Tri-Fortify liposomal glutathione Orange packets travel-friendly glutathione support, HormoneSynergy Portland Lake Oswego

    TriFortify Liposomal Glutathione offers a delicious, highly absorbable liposomal glutathione option for those who prefer liquid over capsules. Dr. Retzler’s pick for enhanced cellular antioxidant support in Portland, OR and nationwide.

  • Magnesium L-Threonate Powder: The Brain-Focused Magnesium We Use Most at HormoneSynergy®

    Magnesium Threonate Powder Magtein for Brain Support

    Magnesium L-Threonate (Magtein®) is one of the most brain-targeted forms of magnesium available—and one of the most popular supplements we recommend at HormoneSynergy® Clinic (Portland & Lake Oswego). Here’s why we love it, how to use it, and how to choose between unflavored and berry powder.

  • S-Acetyl Glutathione: Superior Absorption, Cellular Protection & Antioxidant Support

    RetzlerRx S-Acetyl Glutathione Emothion supplement

    Discover why S-Acetyl Glutathione (Gnosis Biotech Emothion Supplement) from RetzlerRx® delivers superior antioxidant support, absorption, and cellular protection compared to regular glutathione supplements — now shippping USA-wide with 10% off using code EMOTHION.

  • Type Two and Longevity: Caring for Yourself Without Abandoning Others

    Enneagram Type Two longevity image showing self-care, healthy boundaries, receiving support, and caregiver wellness in the HormoneSynergy approach.

    Type Twos often bring warmth, generosity, emotional intelligence, and deep care for others to their health and relationships. But when helping becomes self-abandonment, the body eventually carries the cost. In longevity work, the growth path for Type Two is learning that self-care is not selfish. It is honest care.

  • Fasting Insulin and Metabolic Health

    Fasting insulin and metabolic health showing insulin compensation, normal glucose, HOMA-IR, triglycerides, ApoB, and visceral fat.

    Fasting insulin is a useful early marker of how hard the body is working to regulate blood sugar. It can help identify insulin resistance and metabolic dysfunction before fasting glucose or A1c become clearly abnormal.

  • Type Three and Longevity: When Achievement Becomes Exhaustion

    Enneagram Type Three longevity image showing achievement, recovery, sustainable capacity, and health beyond performance in the HormoneSynergy approach.

    Type Threes often bring energy, drive, adaptability, and follow-through to health. They can execute a plan, track progress, and keep moving. But when achievement becomes the measure of worth, health can become another performance. In longevity work, the growth path for Type Three is learning that rest, honesty, and recovery are not obstacles to success. They are part of health.

  • HOMA-IR and Insulin Resistance: How to Interpret the Number

    HOMA-IR calculation showing fasting insulin and glucose with insulin resistance, visceral fat, triglycerides, ApoB, liver health, and muscle metabolism.

    HOMA-IR combines fasting glucose and fasting insulin to estimate insulin resistance. It can help identify metabolic dysfunction while glucose still looks normal, but the number has to be interpreted carefully. There is no universal HOMA-IR cutoff, and the result is most useful alongside fasting insulin, triglycerides, ApoB, visceral fat, liver health, and the rest of the metabolic picture.

  • Protein for Longevity: The Truth Between “Not Enough” and “Too Much”

    Protein for Longevity: How Much Do You Really Need

    Protein has become the loudest nutrient on the internet—praised as the key to fat loss, muscle, and longevity, and criticized as another overhyped trend. The truth is more nuanced. At HormoneSynergy® Clinic (Portland & Lake Oswego), we take a measured, evidence-based approach to protein that supports muscle, metabolism, and long-term health—without turning every meal into a performance.