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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.

  • I’m Eating Less. Why Am I Not Losing Weight?

    Woman reviewing weight and body composition results with a physician at HormoneSynergy®

    Eating less does not always produce an immediate change on the scale. Water retention, reduced daily movement, sleep, medications, body composition and metabolic adaptation can all affect what happens next.

  • Good Medicine Doesn't Hand Out Supplements "Willy-Nilly"

    HormoneSynergy® Mini Stack: Good Medicine Doesn't Hand Out Supplements Willy-Nilly. Botanical medicine, clinical nutrition, pharmacology, and drug–herb interactions illustrated with supplements, medical textbooks, and a stethoscope.

    A recent professional conversation raised a familiar question: how do thoughtful clinicians decide when supplements are useful, unnecessary, or potentially harmful? A look at botanical pharmacology, clinical judgment, and responsible naturopathic care.

  • Experimental Peptides: Promising Science, Unanswered Questions, and a Changing FDA Policy

    Experimental peptides research and 2026 FDA compounding policy, featuring an investigational peptide vial and molecular imagery. HormoneSynergy® Longevity Medicine.

    Six experimental peptides are receiving renewed attention following a federal compounding policy change. We examine their biological promise, the human research, and what patients should understand about access, uncertainty, and safety.

  • The Longevity Letter: Healthy Aging, New Perspectives & News from HormoneSynergy®

    The Longevity Letter: Healthy Aging, New Perspectives & News from HormoneSynergy®

    Meet Dr. Elise Schroeder, discover what helps healthy habits last, explore salutogenesis, enjoy a Mediterranean recipe from Dr. Retzler's kitchen, and hear Aria's perspective on healthy aging.

  • Mediterranean Sun-Dried Tomato & Garlic Almond Biscuits

    From Dr. Retzler's Kitchen comes a savory Mediterranean-inspired biscuit made with almond flour, sun-dried tomatoes, garlic, extra virgin olive oil, Italian herbs, and Himalayan Tartary buckwheat sprouts. Our inaugural Recipe of the Moment brings together satisfying flavor, dietary fiber, and mostly unsaturated fats in a simple homemade biscuit.

  • Urolithin A, Mitophagy, and Healthy Aging: What Human Research Reveals

    Older adult strength training with a mitochondrial health visualization illustrating urolithin A, mitophagy and longevity research.

    Urolithin A research is moving beyond muscle markers into immune-cell metabolism and cerebral circulation. Review the human trials, the Mitopure® 39% mitophagy claim, and what researchers are studying next.

  • Welcome to HormoneSynergy®, Dr. Elise Schroeder, ND

    Welcome to HormoneSynergy®, Dr. Elise Schroeder, ND

    We're pleased to welcome Dr. Elise Schroeder, ND, to HormoneSynergy® Clinic in Lake Oswego. With a career devoted to women's health, hormone care, and individualized medicine, Dr. Schroeder brings valuable experience and a complementary clinical perspective to our growing practice.

  • Aria Asks: What Are You Assuming About Your Health?

    Aria Asks: What Are You Assuming About Your Health?

    Feeling healthy, collecting more test results, and lowering a biological-age score tell different stories. Aria, HormoneSynergy’s Shepadoodle editorial watchdog, has a question about the one you believe.

  • Protein, Kidney Health, and Healthy Aging: When Restriction May Do More Harm Than Good

    HormoneSynergy® medical editorial illustrating individualized protein intake, chronic kidney disease, muscle preservation, and nutritional health in older adults.

    A 2026 study of 1,861 adults with chronic kidney disease found that very low protein intake was associated with higher risks of kidney failure and mortality. HormoneSynergy® examines how protein recommendations should balance kidney protection, adequate nutrition, muscle preservation, and healthy

  • Obstructive Sleep Apnea, Weight Loss, and Retatrutide: What Two Major Clinical Trials Reveal

    HormoneSynergy® medical editorial illustrating obstructive sleep apnea, metabolic health, and the October 2026 randomized retatrutide clinical trials.

    Two major randomized clinical trials involving 691 adults found substantial reductions in obstructive sleep apnea severity with investigational retatrutide. HormoneSynergy® examines the findings, the relationship between visceral fat and sleep-disordered breathing, established treatment options, metabolic health, and why muscle preservation matters during weight loss.

  • Personalized Nutrition & Nutrient Support: Making Everyday Food Choices Easier

    Personalized Nutrition & Nutrient Support: Making Everyday Food Choices Easier

    Knowing that nutrition matters does not always make it easier to decide what to eat or which supplements are appropriate. HormoneSynergy® combines practical food education with assessment-guided nutrient support to help people put recommendations into practice.

  • APOE4, Brain Blood Vessels, and Cellular Cleanup: What New Research Reveals

    Editorial illustration of brain blood vessels and surrounding support cells accompanying an article about APOE4 and cellular cleanup.

    Two studies examine how APOE4 affects the cells supporting brain blood vessels and the machinery that breaks down proteins inside astrocytes. The findings offer promising research directions and a clearer understanding of what remains to be demonstrated in patients.