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Jason Fung

Jason Fung is a Canadian nephrologist and author whose work focuses on obesity, type 2 diabetes, intermittent fasting, and metabolic health. He is best known for The Obesity Code, The Diabetes Code, and The Complete Guide to Fasting, which helped popularize fasting-centered approaches to weight loss and insulin resistance.

Biography & Author's Journey

Jason Fung is a Canadian nephrologist and author whose public work grew directly out of clinical frustration. He grew up in Toronto, entered the University of Toronto at 17 to study biochemistry, completed medical school there by 23, trained in internal medicine, and then pursued nephrology at the University of California, Los Angeles before returning to Toronto in 2001. In practice, he repeatedly saw type 2 diabetes leading patients toward kidney disease, and that experience became the central turning point of his career. By the mid-2000s, his reading in nutrition research and his dissatisfaction with standard diabetes care pushed him toward a sustained interest in obesity, insulin resistance, and the role of diet in chronic disease. ((https://www.thefastingmethod.com/my-journey/))

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Quotes

quote
Insulin causes weight gain
-A Short Primer on How to Lose Weight – What to Eat and When to Eat
quote
Obesity is a multi-factorial disease
-Addendum to Do all Diets Fail?
quote
The term diabesity is the unification of the words ‘diabetes’, referring to type 2, and ‘obesity’
-Diabesity – T2D 18
quote
Most people think that eating too much causes obesity and eating less will enable us to lose weight
-The Astonishing Overeating Paradox
quote
If eating too much causes obesity, then we should be able to overfeed subjects in an experimental setting and they should gain weight
-The Astonishing Overeating Paradox – Calories Part X
quote
Obesity is a hormonal, not a caloric, imbalance
-My Single Best Tip for a Healthy Weight
quote
We think that eating too many calories causes obesity
-The Obesity Epidemic - Root Causes

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Community Voices

"Jason Fung is a nephrologist and a New York Times-bestselling author of many books including The Obesity Code and The Diabetes Code"

BBC Science Focus

"Jason Fung has a gift for explaining complex science clearly and delivering it with the perfect, telling anecdote"

Nina Teicholz

"Jason Fung nails it again in The Hunger Code"

Dan Buettner

"Jason Fung, MD uses Ockham's razor to simplify the management of type 2 diabetes"

Family Medicine

"With rich scientific support, Dr. Jason Fung has sounded a clarion call to re-evaluate how we view and treat diabetes"

Benjamin Bikman

"Dr. Jason Fung has done it again"

Steven R. Gundry

"Dr. Jason Fung presents a novel, comprehensive model of obesity that delivers unexpected insights into healthy eating"

Indian Journal of Medical Sciences

"Dr. Jason Fung's explanation of insulin resistance and the accompanying insulin model of obesity is original, brilliant and game changing"

Zoë Harcombe

"Dr. Jason Fung triumphs in explaining the core underlying causes of obesity and manages to simplify it in a way that anybody can understand"

Sam Feltham

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