Dr. Mark Hyman, MD

Hyman's functional medicine approach starts from a different question than most nutrition advice. Instead of asking how many calories are in a food, he asks what that food does to the body's hormones and systems over time. Blood sugar regulation sits at the center of that approach, which is why The Blood Sugar Solution treats insulin resistance as the root cause to reverse, not a lab number to manage on its own.

Eat Fat, Get Thin makes an argument that runs directly against decades of low-fat advice: dietary fat suppresses insulin more effectively than the low-fat, high-carbohydrate pattern it replaced. RealFoods scores food the same way, on hormonal impact rather than fat content in isolation, which is why a food's WI Score can look very different from where it would land on a traditional low-fat plan.

Food: What the Heck Should I Eat? extends the same myth-busting approach to a wider set of everyday foods, sorting them by whether they raise or suppress insulin rather than by fat or carbohydrate content alone. Hyman's focus on ultra-processed food as a driver of type 2 diabetes is especially relevant for readers managing the condition themselves or supporting a family member who is. The articles below go deeper into blood sugar regulation and insulin resistance.

Hyman's role directing the Cleveland Clinic Center for Functional Medicine puts his root-cause approach inside mainstream medicine rather than outside it, which has helped move insulin-focused nutrition science from the margins toward more conventional acceptance. His broader argument, treat the metabolic cause rather than the downstream lab result, is the same logic RealFoods applies at the level of a single meal. A high WI Score is meant to flag the hormonal cause of weight gain before it shows up as a diagnosis, not after.