On August 29, 2025, the BSI Medical Society Journal Club, hosted by Bob Kaplan with contributions from Pete Shaw, examined “Insulin Resistance is a Cellular Antioxidant Defense Mechanism” (Hoehn et al., 2009), a paper proposing that insulin resistance (IR) may serve as a protective cellular response to nutrient excess rather than a pathological defect. The discussion highlighted that across multiple experimental models—chronic insulin exposure, inflammation, corticosteroids, and lipid overload—insulin resistance coincided with increased mitochondrial reactive oxygen species (ROS), particularly superoxide. Hoehn’s team demonstrated that reducing mitochondrial ROS through uncouplers, electron transport chain inhibitors, or mitochondria-targeted antioxidants restored insulin sensitivity, while inducing ROS directly could trigger IR. The group underscored how these findings place mitochondrial ROS at the crossroads of energy metabolism and signaling, reframing insulin resistance as an adaptive mechanism to limit further nutrient influx and oxidative stress when cells are energetically saturated.
To broaden this framework, Bob and Pete connected Hoehn’s findings to the companion paper “ROS Are Good” (Mittler, 2017), which argues that ROS are not merely toxic byproducts but essential signaling molecules required for cellular proliferation, differentiation, and metabolic regulation. Together, the two studies highlight a continuum of redox biology in which ROS serve as both life-supporting signals and protective brakes against energy overload. In this light, insulin resistance represents the complementary “energy surplus” signal—a redox-based mechanism that protects mitochondria from excessive substrate flux. The presenters also examined the nuanced implications for diet, fat quality, and antioxidant therapy, warning that indiscriminate ROS suppression might impair essential signaling. Participants reflected on how this reframing challenges conventional approaches to diabetes treatment, suggesting that insulin resistance may be a context-dependent, protective response rather than a simple metabolic failure.
A 10-minute summary of the webinar is available here free, for anyone, while the full video is available for Medical Society Members and MetFix affiliates in their dashboard.
Bob Kaplan is an independent research analyst. Bob previously served as director of research at Early Medical, contributing to The Drive podcast with Peter Attia and its other properties. Kaplan was a researcher at the Nutrition Science Initiative (NuSI), and an exercise physiologist at the University of Nevada, Las Vegas. His current and previous research interests include meta-research, chronic diseases, bioenergetics, exercise physiology, and nutrition.
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Metabolic health, medical education, and the case for bringing clinicians and coaches together
At the 2026 Unbreakable Health Retreat in Miami, Emily Kaplan hosted a panel with Bob Kaplan, Professor Thomas Seyfried, and Dr. Derek Lee on what it means to treat cancer as a metabolic disease. They discussed the glucose-ketone index (GKI), nutritional ketosis, and strategies aimed at restricting the fuels cancer cells depend on while considering how metabolic therapy can fit alongside standard cancer treatment.
The conversation also addressed the practical realities patients face when trying to pursue a metabolic approach within the conventional oncology system, including questions about nutrition, repurposed drugs, inherited cancer risk, and how to evaluate different treatment options. Seyfried and Lee connected these clinical questions back to mitochondrial dysfunction, fermentation, and the metabolic vulnerabilities that may offer additional targets for cancer treatment.
An abbreviated version of this discussion is available here, for free.
At the 2026 Unbreakable Health Retreat in Miami, Professor Thomas Seyfried presented the case that cancer is fundamentally a mitochondrial metabolic disease rather than primarily a genetic one. He contrasts the dominant somatic mutation theory with a metabolic model in which impaired mitochondrial respiration drives a shift toward fermentation, dysregulated cell growth, and the mutations commonly associated with cancer.
Citing the work of Otto Warburg and research from his lab at Boston College, Seyfried explains how cancer cells rely heavily on fermentable fuels—particularly glucose and glutamine—and why mitochondrial dysfunction sits upstream of many of the genetic abnormalities seen in tumors. He also discusses reactive oxygen species, altered cellular signaling, and the role of mitochondria in regulating cell growth and behavior.
The presentation then turns to the therapeutic implications of this model. Seyfried explains strategies aimed at placing tumor cells under metabolic stress by restricting the fuels they depend on, including ketogenic metabolic therapy and approaches targeting glucose and glutamine. For Seyfried, the therapeutic target follows directly from the biology: restrict the fuels cancer cells depend on, exploit their metabolic weaknesses, and treat mitochondrial dysfunction as the central feature of the disease.
An abbreviated version of this discussion is available here, for free.
MetFix and BSI Members can view the full 54-minute video.
