Sarah Hallberg is the Medical Director at Virta Health and a physician who has spent nearly two decades treating patients with obesity and type 2 diabetes. In the first half of this episode, Sarah discusses how she became a huge believer in the efficacy of carbohydrate restriction for the treatment of type 2 diabetes through her research and clinical experience. Sarah challenges the common beliefs about the role of dietary fat and carbohydrate on the plasma makeup of fatty acids and triglycerides. She also expresses the importance of understanding early predictors of metabolic illness—highlighting one particular fatty acid as the most important early predictor—before finishing with a discussion about how doctors might be able to personalize patients’ metabolic management in the future. In the second half of this episode, Sarah tells the personal story of her own lung cancer diagnosis. She talks about dealing with her grief, deciding to continue her work while prioritizing her family, and how she devised a plan to extend her survival as long as possible.

We discuss:
00:00:00 – Intro
00:00:10 – How Sarah discovered the profound impact of carbohydrate restriction for reversing obesity and type 2 diabetes
00:13:30 – Prediabetes and metabolic syndrome: prevalence, early signs, and the importance of treating early
00:27:45 – Overview of fatty acids, how they are metabolized, and understanding what you see in a standard blood panel
00:33:45 – The relationship between diet composition and metabolic markers
00:47:50 – Why palmitoleic acid is such an important biomarker
1:00:30 – The best early indicators of metabolic disease
1:07:45 – Personalized management of metabolic illness
1:16:50 – Sarah’s cancer diagnosis and the beginning of her journey
1:30:00 – The emotional impact of a devastating diagnosis
1:40:30 – Sarah’s plan to extend survival
1:52:15 – Sarah’s aggressive treatment plan
2:05:00 – Life-threatening complications and the return of her cancer
2:18:26 – Sarah’s reflections on her approach to life with chronic cancer and balancing her time

Show notes page:


The Peter Attia Drive is a weekly, ultra-deep-dive podcast focusing on maximizing health, longevity, critical thinking…and a few other things. With over 30 million episodes downloaded, it features topics including fasting, ketosis, Alzheimer’s disease, cancer, mental health, and much more.

Peter is a physician focusing on the applied science of longevity. His practice deals extensively with nutritional interventions, exercise physiology, sleep physiology, emotional and mental health, and pharmacology to increase lifespan (delay the onset of chronic disease), while simultaneously improving healthspan (quality of life).

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