Casey Means

At a glance

• Casey Means is an American physician, entrepreneur and author focused on metabolic health. She studied medicine at Stanford and left her training as an ear, nose and throat surgeon.
• She co-founded Levels, a company offering continuous glucose monitors and an app to people without diabetes.
• With her brother Calley Means she wrote Good Energy (2024), arguing that many chronic diseases are linked to disrupted cellular energy production.
• In 2025 President Trump nominated her as Surgeon General, the top public-health adviser in the US.
• Her advice mainly concerns unprocessed food, fibre, sleep, movement and daylight. Critics point to the lack of evidence for glucose monitors in healthy people and to her commercial interests.
• For longevity, she matters because she put metabolic health high on the public agenda.
• Takeaway: you don’t need a sensor to start; eat more fibre and less ultra-processed food, and take a short walk after meals.