The Diary of a CEO with Steven Bartlett

Episode: The Diabetes Doctor: 80% Of Adults Are Heading For Chronic Disease! Keto’s Shocking Effect On Your Brain!
Guest: Dr. Andrew Kutnick
Date: September 8, 2025

Episode Overview

This episode features Dr. Andrew Kutnick, a renowned research scientist specializing in metabolic health, diabetes, and the ketogenic diet. He and host Steven Bartlett conduct a deep dive into chronic disease trends, the surprising power of therapeutic carbohydrate restriction, misconceptions about the keto diet, and the latest science around metabolic health, brain function, and physical performance. With personal anecdotes and research-backed insights, Dr. Kutnick shares practical, science-driven strategies to help listeners prevent chronic diseases, optimize cognition, and thrive in today's challenging food environment.

Key Discussion Points & Insights

1. Dr. Andrew Kutnick’s Mission and Personal Journey

• Reversing Chronic Disease: Dr. Kutnick, having struggled with obesity and type 1 diabetes since childhood, sought to understand health beyond standard medical advice, ultimately reversing one condition and managing the other.
  • “The core of my mission, Stephen, is really to empower individuals to take control of their own health. It’s empowering them with science, you know, bridging science to actual action.” (03:23)
• Early Struggles with Obesity: Despite following traditional health advice, he faced increasing weight and developed chronic illness, highlighting flaws in common nutritional guidance.
  • Obesity rates among children have quadrupled in 30 years; 68% of US adults are now obese. (05:47)

2. Understanding Metabolic Health & Insulin

• Metabolism Simplified: Explains that metabolism is how bodies convert food into energy and store nutrients, primarily via glucose and insulin.
  • “Insulin is basically the Uber, which takes things out of your blood and puts them where they need to be.” (07:15; Bartlett)
• Impact of Obesity on Insulin Sensitivity: Even early obesity severely impairs insulin sensitivity, increasing chronic disease risk before symptoms manifest. (07:15–08:10)
• Devices for Monitoring: Describes his use of an insulin pump and continuous glucose monitor (CGM), and the limitations of even advanced tech. Real-time data highlight the direct impact of diet on glucose regulation. (08:10–10:07)

3. The Dangers of High Blood Sugar

• HbA1c as Predictor: Chronic elevated blood sugar, as measured by HbA1c, is “incredibly powerful at predicting future risk for diseases of the eye, kidney, or even cardiovascular disease.” (10:17)
• Glucose Control Hierarchy: Emphasizes glucose regulation as the foundation of metabolic health—“Glucose control sits at the very top of that pyramid.” (11:53)

4. The Ketogenic Diet: History, Science & Myths

• Ancient & Modern Evidence: Nutrition as therapy isn’t new—low-carb diets were used to treat diabetes and epilepsy long before insulin was discovered.
  • “It’s actually only recently that we’re rediscovering century-old wisdom of what nutrition can do for overall health...” (13:34)
• What Keto Really Is (and Isn’t): Challenges stereotypes—well-formulated keto includes green, high-fiber vegetables, quality protein, and healthy fats, not just “steak and bacon.” (14:34)
• Physiology & Evolution: Ketosis evolved as a survival mechanism for periods of food scarcity, enabling the body to fuel the brain and muscle with ketones when glucose is low. (16:45–19:01)

5. Cognitive and Performance Effects of Ketosis

• Mental Clarity on Ketones: Both Dr. Kutnick and Bartlett notice substantial improvements in focus and cognitive endurance during ketosis.
  • “I feel like I’m more effective in communication and thinking when I’m on the ketogenic diet...” (19:01; Bartlett)
  • Blood sugar “highs” and “lows” correlate strongly with symptoms like fatigue, irritability, lack of concentration, and brain fog. (19:40–20:39)
• Live Glucose Experiment: Dr. Kutnick eats oranges on-air to show a real-time CGM/insulin response, demonstrating how even “healthy” fruits spike glucose and insulin—especially relevant for diabetics and those with metabolic dysfunction. (22:12–25:23)

6. Practical Keto Insights: What Works and Food Industry Tricks

• Net Carbs & Food Labels: Warns listeners not to trust “keto-friendly” food labels, as manufacturers can manipulate ingredients to mimic the glycemic effect of sugar while advertising “zero sugar.” (25:23–26:50)
  • “The food environment nowadays, you essentially need almost a PhD in nutrition or biochemistry to walk into a grocery store and be able to understand what the hell’s on the label.” (25:30)
• Impact on Type 1 Diabetes: A decade of keto brought Dr. Kutnick stable blood sugar and dramatic insulin reductions. Traditional care rarely achieves this, while poor control leads to measurable brain and vascular damage—even in children. (26:50–33:07)

7. Carbohydrate Restriction as Therapy

• Therapeutic Carbohydrate Restriction: Restricting carbs isn’t just weight loss—it’s a powerful, evidence-based intervention for diabetes, cognitive decline, and potentially even serious mental illness.
  • “...for those patients who have chronic disease, which is unfortunately the overwhelming majority of us, yes, restricting carbohydrates can have a powerful therapeutic effect on diseases like type 2 diabetes.” (34:38)
  • 93% of Americans now show signs of metabolic disruption. (36:01)

8. Longitudinal and Large-Scale Research

• 10-Year Case Study: Details the longest study of its kind—a type 1 diabetes patient on keto for a decade saw normalized blood sugars, reduced insulin (by 40%), and better cardiovascular health despite increased LDL, challenging prevailing cholesterol fears. (36:01–39:04)
• Largest Dataset on Keto in T1D: In 46,000+ patients, 70% normalized glucose control on keto. (36:20)

9. Physical Performance and Keto Adaptation

• Endurance & Intensity: While short-term studies find reduced performance on keto, true adaptation takes 4+ weeks. Dr. Kutnick’s controlled studies show athletes maintain peak performance, with the highest recorded fat-burning rates, even at high intensities. (45:12–52:52)
  • “They had no deterioration in performance at four weeks, at the four week mark in a form of exercise that we would expect would be extremely glucose dependent...” (51:19)
• Muscle Mass Maintenance: Keto does not impede muscle gain or cause muscle loss; rapid initial "weight loss" is mostly water due to sodium excretion. Maintaining muscle hinges on sufficient protein, overall calories, and resistance exercise. (61:14–63:10)

10. Exogenous Ketones and Brain Health

• Supplemental Ketones: "Exogenous" ketones can quickly increase blood ketone levels, providing many similar benefits as the keto diet including improved cognition and metabolic flexibility, used in research settings from military to Alzheimer’s patients.
  • “When you consume them it rapidly changes metabolism...it has a blood glucose lowering effect, directly impacts inflammation... and increases our antioxidant capacity...” (53:16–56:34)
• Scientific Findings: Ketones increase brain network stability by up to 87% over glucose (58:27), and delay cognitive decline and muscle wasting in aging and disease.
• Appetite Suppression: Both dietary and exogenous ketones substantially reduce appetite. (63:45)

11. Food Environment, Cravings, and Practical Advice

• Processed Food & Palatability: The food industry strategically engineers products to maximize dopamine responses—mixing sugar, fat, and salt to override natural hunger cues, making it hard to feel satisfied and easy to overeat. (66:54–68:51)
• Liquid Calories & Blended Foods: Warns against fruit juices, smoothies, sodas—these spike glucose and hunger more than whole foods. Blending removes structural barriers, accelerating sugar absorption and disrupting hormones like GLP-1. (69:15–71:15)
• GLP-1, Semaglutide/Ozempic: Popular hunger-suppression drugs use GLP-1 receptor agonists, but the natural goal is stable, moderate release from whole foods, not constant overstimulation. (71:15)

Actionable Advice & Takeaways

Dr. Kutnick's Practical Recommendations (74:08)

1. Be Conscious of Food Choices: Treat food with the same seriousness as medicine—prioritize whole foods, reduce processed foods, and avoid most liquid calories.
2. Carb Restriction for Metabolic Disorders: For those with diabetes, obesity, or metabolic syndrome, reducing carbohydrate intake can dramatically improve and even reverse disease progression.
3. Regular Exercise: Exercise is essential for overall and metabolic health. Dr. Kutnick recommends daily movement combining resistance (weightlifting, jiu jitsu) and aerobic/cardio.
4. Prioritize Sleep: Good quality sleep, alongside diet and exercise, is a pillar of long-term health.

Foods to Be Cautious With:

• Liquid Calories (Soft drinks, juice, smoothies): Aggressive glucose and insulin spikes.
• Processed or “Keto-Friendly” Packaged Products: Label claims are often misleading.
• Refined Carbs: Cereals, white rice, bread, potatoes, pasta, pastries, dried fruit—cause pronounced blood sugar response, especially problematic for already-impaired metabolism.

On Trying the Ketogenic Diet:

• Everyone’s Different: Individual response can vary widely; real-life experimentation is needed to know if keto will benefit you personally.
  • “You will never know the potential of its benefit or lack thereof if you don’t try." (84:30)
• Don’t Rely on Averages: Study outcomes reflect averages; you might be an outlier.

Notable Quotes & Memorable Moments

• On the food industry:
  “The food environment nowadays, you essentially need almost a PhD in nutrition or biochemistry to walk into a grocery store and be able to understand what the hell’s on the label.” (25:30 – Kutnick)

• On carbohydrate restriction as medicine:
  "...Carbohydrate restriction isn’t just weight loss—it’s a powerful, evidence-based intervention for diabetes, cognitive decline, and potentially even serious mental illness." (34:38 – Kutnick)

• On personal experimentation:
  "What I would say is that you will never know the potential of its benefit or lack thereof if you don’t try." (84:30 – Kutnick)

• On the power of ketones for the brain:
  "Ketones increased the stability of brain networks. In contrast, glucose decreased the stability of the network. The Network stability was 87% greater after ketone consumption than stability measured after glucose consumption." (58:27 – Bartlett referencing study)

Timestamps for Key Segments

| Time | Segment Description | |---------|-----------------------------------------------------------------------| | 00:30 | Dr. Kutnick introduces himself and “bridging science to action” | | 05:47 | Dr. Kutnick’s childhood obesity and early metabolic challenges | | 07:15 | Insulin: The “thermostat” of blood sugar explained | | 10:17 | Why high blood sugar is so dangerous; HbA1c and chronic disease | | 13:34 | Historical use of ketogenic diets and re-discovery in modern science | | 14:34 | What a “real” ketogenic diet looks like, common misconceptions | | 19:01 | Ketones, cognitive clarity, and glucose variability | | 22:12 | Live CGM/insulin experiment: eating three oranges | | 25:30 | Food industry “keto” label tricks explained | | 26:50 | Impact of keto on type 1 diabetes; rarely seen stable sugar levels | | 36:01 | 10-year longitudinal study: keto in type 1 diabetes | | 45:12 | Keto adaptation and athletic performance, debunking the myths | | 52:52 | Exogenous ketones: science and practical uses | | 58:27 | Ketones and brain network stability—research findings | | 61:14 | Keto, appetite, and muscle mass explained | | 66:54 | How processed food hijacks brain reward systems | | 69:15 | Why smoothies and juices are worse than whole fruit | | 74:08 | Dr. Kutnick’s practical life advice | | 79:06 | Surprising “healthy” foods with big glucose impact | | 84:30 | Should everyone try the ketogenic diet? Individual responses matter |

Closing Reflections

The episode is an urgent, scientific call to challenge what we’ve been told about “healthy” food, especially for the majority of adults already on the spectrum of metabolic syndrome. Dr. Kutnick makes clear that chronic diseases are largely preventable—and even reversible—using interventions as simple (and as powerful) as diet and lifestyle. The ketogenic approach stands out not just for diabetes but for cognition, performance, and mental health.

Final advice:
“Good nutrition tailored to your specific needs, exercising as much as you can and getting good sleep are the pillars of health. If you don’t have those corrected, then you’re wasting your time everywhere else.” (78:40 – Kutnick)