Dr. Eric Berg, DC
Doctor of Chiropractic, Nutritional Educator
Dr. Eric Berg has educated millions through his YouTube channel and books on the link between insulin, cortisol, and body fat storage. His practical frameworks for ketogenic eating and intermittent fasting align directly with the insulin-first logic of the RealFoods WI Score, and his emphasis on electrolytes and nutrient density informs how RealFoods evaluates food quality beyond the glucose curve.
Berg's work adds a second hormone to the insulin story: cortisol. Chronic stress keeps cortisol elevated, and elevated cortisol makes insulin resistance worse, which is why he teaches ketogenic eating and fasting together rather than as separate tools. Lowering insulin through food choices does less if cortisol is working against it at the same time, and Berg's frameworks are built to address both.
The other piece of Berg's teaching that shows up in RealFoods is nutrient density. He has long argued that electrolyte and micronutrient shortfalls, not just insulin, undermine energy and fat loss, especially for anyone changing how they eat. The WI Score's focus on food quality beyond the glucose curve, not just how a food affects blood sugar but what it actually delivers nutritionally, reflects that same emphasis.
The Healthy Keto Plan combines his ketogenic and fasting recommendations into one practical protocol aimed at regulating insulin and helping the body adapt to burning fat for fuel. The fasting-specific pages below go deeper into the mechanics of the eating windows that protocol relies on.
Berg has built his following specifically around weight loss without calorie counting, which puts him in direct alignment with how RealFoods approaches food. Rather than asking people to track totals, his content walks through which foods and habits move insulin and cortisol in the right direction, then lets the results follow from there. That practical, video-first teaching style has reached an unusually large audience for metabolic health content, and much of it distills down to the same short list of levers: what to eat, when to eat it, and how to manage stress so cortisol does not undo the insulin benefits of the first two. RealFoods condenses that same list into the WI Score and the fasting tracker, giving the food side of Berg's teaching a single number and the timing side a visual window. His emphasis on nutrient deficiency also carries into how RealFoods thinks about weight loss without calorie counting more broadly: a food that scores well on hormonal impact should still be nutrient dense, not just low in whatever a person happens to be avoiding that week.
Key works
The Healthy Keto Plan (2019)
A practical guide to combining ketogenic eating with intermittent fasting to regulate insulin and accelerate fat adaptation.
Areas of expertise
- Insulin and Fat Storage
- Ketogenic Nutrition
- Intermittent Fasting
- Cortisol and Stress Hormones
- Nutrient Deficiency
- Metabolic Health
- Weight Loss Without Calorie Counting
