Dr. Jason Fung, MD


Dr. Jason Fung is a Canadian nephrologist. He’s a world-leading expert on intermittent fasting and low carb, especially for treating people with type 2 diabetes. He has written and he co-founded the Intensive Dietary Management program.

Dr. Fung has his own website at thefastingmethod.com.

Dr. Fung graduated from the University of Toronto and completed his residency at the University of California, Los Angeles. He lives and works in Toronto, Canada.

Dr. Fung occasionally collaborates with Team Diet Doctor on fasting related topics. Together we want to make it simple for people to understand and implement intermittent fasting, to improve their health. Below is some of the material with Dr. Fung on Diet Doctor.

About Dr. Fung

Watch Dr. Fung’s brief presentation above.


Written profile

Dr. Jason Fung: Dismantling diet dogma, one puzzle piece at a time


The fasting video course


The type 2 diabetes video course



  • Are all carbohydrates equally bad?
  • What to do instead of counting calories
  • The perfect treatment for diabetes and weight loss
  • Do you have to count calories to lose weight?



    The 2 big lies of type 2 diabetes
  • The cause of obesity
  • A new paradigm for type 2 diabetes
  • Therapeutic fasting
  • The key to obesity
  • PCOS and insulin resistance
  • Understanding and treating type 2 diabetes – Dr. Jason Fung




  • Intermittent fasting for beginners - Draft cta
  • Intermittent fasting for beginners
  • Intermittent fasting for beginners - PT


Q & A

Ask Dr. Jason Fung


More with Dr. Fung

Dr. Fung is also on Twitter, Facebook, Instagram, LinkedIn and YouTube.


The Obesity CodeThe Complete Guide to Fastingthe-diabetes-code (1)

Dr. Fung’s books The Obesity Code, The Complete Guide to Fasting and The Diabetes Code are available on Amazon.1  

Other publications

BMJ Case Reports 2018: Therapeutic use of intermittent fasting for people with type 2 diabetes as an alternative to insulin


Does sugar-free gum break a fast?
The biochemistry of insulin resistance
Several new studies and the concept of "calories"
How do you repair low metabolism after a low-calorie diet?
Physician success story – Dr. Esther Kawira
Fasting for reversing type 2 diabetes and obesity
How to transition from weight loss to maintenance mode?
How fasting made all the difference for Jennifer
After trying every diet, Karen reaches her goals by trusting the process
Sandra’s incredible weight-loss journey
Would you ever put people with type 2 diabetes on insulin?
Controlling hunger – part 2
Why is blood glucose elevated when fasting?
Video post: What is insulin resistance?
Video post: What is intermittent fasting?
What is the optimal fast frequency?
Theories of aging
Video post – what breaks a fast?
What is aging?
The longevity solution
Longevity lessons from the Blue and ‘unBlue’ Zones
A different path to the same destination
Free weight loss resources from IDM
"Can you get type 2 diabetes again once you've reversed it?"
Chemicals that cause cancer
The blame for fat shaming
Nutrition and your doctor
"How can I lose weight when no diets are working?"
Announcing the Low Carb MD Podcast
Does fasting burn muscle?
PCOS, anovulatory cycles and hyperinsulinemia – PCOS 9
PCOS and hyperinsulinemia – PCOS 8
Could you fast for health without weight loss?
My single best weight-loss tip
With one foot in the grave, Robert turned things around and lost 200 lbs
PCOS and hyperandrogenism – PCOS 7
PCOS and associated conditions – PCOS 6
Are there any dangers fasting while breastfeeding?
PCOS and obesity – PCOS 5
The truth about salt
How to worsen diabetes: follow the worst of the ADA and CDA advice
The obesity epidemic
The difficulties of diagnosing PCOS - PCOS 4
'Is it okay to have cheat days?'
How Dolly turned her obesity and metabolic syndrome around
The lucrative story of cotton seed oil
Potentially beat disease with crossfit, low carb and intermitting fasting
Hyperandrogenism – PCOS 3
Diabetes of bearded women – PCOS 2
Infertility, PCOS and the IDM program
What? Is fasting NOT crazy and stupid?
Why does blood sugar increase during a fast?
When we eat is as important as what we eat – and this is why
Debunking the debunkers
What and when to eat to reduce insulin
Understanding obesity – the key to successful weight loss
Why there's more to weight loss than restricting calories
How do you increase the length of your fasts without stressing the adrenals?
The Diet Wars or what you should eat to lose weight
The corruption of evidence-based medicine
New book: The Diabetes Code
Cutting calories won't solve your weight issues – do this instead
When should you eat if you're working night shifts?
Moving away from the theory that cancer is simply a result of random mutations
Do you recommend going in and out of ketosis?
The Warburg Effect and cancer
Attacking cancer's weakness: not its strengths
The 6 common features of cancer
The seed and soil of cancer – or why we need to zoom out to understand it
The powerhouses of the cell and human diseases
What are the good and bad effects of fasting?
The ancient secret to 'hacking' the aging process
Why carbs and exercise are not the answers to reverse type 2 diabetes
The most important thing – practicing fasting safely
What diet causes cancer?
Is fasting every single day counterproductive?
Autophagy – a cure for many present-day diseases?
Fasting, cellular cleansing and cancer – is there a connection?
Treating modern diseases like we're stuck in the 19th century
The corruption of the medical system and how it should change
Can just the sight of food raise insulin?
Darwin's theory of evolution or why cancer is not simply a result of random mutations
The history and future of cancer
Gleevec's false dawn or how we're losing the war on cancer
The Procrustean bed or how to make cancer into a disease of random mutations
The power of nutritional treatment
'How many times should I eat during my eating window?'
Why we're losing the war (on obesity, type 2 diabetes and cancer)
How to eat: fast and break-fast
The sword of Damocles and the Obesity Code podcast
Why you should avoid miracle weight-loss cures
How do you add back calories without gaining weight?
The mistake of confusing the cause of cancer
Cancer as an environmental disease
Cancer as an endocrine disease
Hyperinsulinemia and cancer
Obesity and cancer
How to tell whether you are ready for maintenance or are in a plateau?
Fasting and diseases of excessive growth
How do you beat food cravings?
The corruption of academic medicine
Are trouble sleeping and anger common while fasting?
Medications that actually work for type 2 diabetes
Failure of the glucotoxicity paradigm in type 2 diabetes
How NOT to treat diabetes
Are supplements necessary?
Insulin toxicity and modern diseases
Grazing or fasting – and why it matters for weight loss
"Life. Is. Good."
Can teenagers fast?
Why high blood sugar is not the main problem in diabetes
Towards a cure for type 2 diabetes
"Feeling amazing about life again"
Fatty pancreas and the development of type 2 diabetes
The unrecognized second phase of developing type 2 diabetes
How a thin person with diabetes reversed her type 2 diabetes
Is bariatric surgery like fasting in type 2 diabetes treatment?
How to not get hungry: Fasting and ghrelin
Does eating 6-7 times a day make you eat less?
Why could I eat what I wanted before and not gain weight?
Why type 2 diabetes is a reversible dietary disease
Why red meat won't kill you
Intermittent fasting does not cause muscle loss
Do you have to eat a minimum amount of carbs?
Triglycerides and heart disease – what's the connection?
How carbs affect your cholesterol
Does eating extra fat make you fat?
Why does sugar make people fat?
What’s the difference between a ketogenic and a low-carb diet?
Intermittent fasting vs. caloric reduction – what's the difference?
Fructose and fatty liver – why sugar is a toxin
Fructose and the toxic effects of sugar
Fasting and muscle mass
The ancient secret of weight loss
A trip to DiabetesVille
How Gina really healed herself from obesity and metabolic syndrome
Fasting and hunger
Does skipping breakfast lead to a higher risk of type 2 diabetes?
Insulin and fatty liver disease
Does fat cause type 2 diabetes?
Fasting and exercise
Why high insulin precedes type 2 diabetes
Can intermittent fasting cause hormonal imbalances in women?
Fasting myths
A new paradigm of insulin resistance
Insulin causes insulin resistance
How fasting reverses type 2 diabetes
What is your ideal weight?
Fatty liver disease or how not to make 'foie gras' at home
Searching for the X factor
Fasting and re-feeding syndrome
How fasting affects your physiology and hormones
Obesity – solving the two-compartment problem
Why fasting is more effective than calorie counting
Lose weight on Twinkies? Big Soda's strategy to make us believe that it is all about calories
Can I use cream in my coffee during fasting?
Fasting and cholesterol
The calorie debacle
Fasting and growth hormone
The Complete Guide to Fasting is finally available!
How does fasting affect your brain?
Diabesity: Why diabetes and obesity stem from the same problem
"Do you have any suggestions to improve sleep when fasting?"
Complications of diabetes – a disease affecting all organs
How to renew your body: Fasting and autophagy
Longer fasting regimens – 24 hours or more
Why high blood sugar is not the main problem
More practical tips for fasting
Short fasting regimens – less than 24 hours
Practical tips for fasting
A behind-the-scenes look at medical education
The common currency in our bodies is not calories - guess what it is?
"The Big Fat Fix" movie review
"You can't handle the truth" – Dr. Gary Fettke censored for recommending low carb
How to use antibiotics: Why less is more
The futility of blood sugar lowering by medications in T2D
How obesity can protect from disease
How Kevin Hall tried to kill the insulin hypothesis with pure spin
My top 8 weight-loss hacks
How to reverse type 2 diabetes - the quick start guide
Can yo-yo dieting break people's metabolism?
Women and fasting
A new paradigm of insulin resistance
How Gino reversed his type 2 diabetes by doing the opposite
Reversing type 2 diabetes: Sunny and Cherie
Why the first law of thermodynamics is utterly irrelevant
How to fix your broken metabolism by doing the exact opposite
How NOT to write a diet book
Longer fasts, ketoacidosis and weight regain
The Biggest Loser FAIL and that ketogenic study success
The diabetes economy
Can kids skip breakfast?
Dr. Jason Fung answers questions about intermittent fasting
Ask our expert about diabetes and intermittent fasting
Diabetes and the dawn phenomenon
The 7 practical benefits of fasting
Q&A: what kind of fasting should I do?

Potential conflicts of interest

Updated August 21, 2019.

Dr. Fung is a co-owner in the Diet Doctor company.

Dr. Fung receives money for treating patients with kidney disease in hospital for general internal medicine and obesity medicine. He owns parts of his medical practice.

He is also a part-owner at Intensive Dietary Management corporation, which provides education and support for fasting.

Dr. Fung receives money from his books The Obesity Code, The Diabetes Code, The Complete Guide to Fasting and The Longevity Solution, and articles on medium.com.

Dr. Fung speaks at conferences and occasionally receives speaking fees.

He has a YouTube channel discussing nutrition and fasting.

Dr. Fung eats a low-carbohydrate diet and fasts regularly.

Dr. Fung drinks tea daily. He receives consulting fees from Pique Tea.



Team Diet Doctor

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