Notes on The Obesity Code by Jason Fung

I heard about the book The Obesity Code: Unlocking the Secrets of Weight Loss by Dr. Jason Fung from my wife, who heard about it from her doctor friends. She insisted I read it, and I did it almost as a favor to her (I wasn't as interested in the subject matter). She wanted to talk about the content with me, and I thought I'd quickly get through it, and that would be that. I didn't even open up a Google doc to take notes on it because I initially didn't care.

But about halfway through chapter 1, realized I couldn't not take notes. I was learning so much and enjoying the book so much that I had to take notes. I had gotten some sense for the book's conclusions from other things I've read (like Tim Ferriss's books and podcast that have discussed the same solutions like intermittent fasting, slow carb, etc.), so it wasn't like the subject was brand new to me. It's just that it was explained so clearly and hooked me so well with its writing that I ended up learning a lot more than I expected. And most importantly, I'm actually making changes based on what I learned.

Thankfully I'm not overweight, but I still want to eat healthy and avoid doing things that can harm my health in the long run. That's actually a question I was hoping the author would answer but didn't in this book: which of the lessons/guidelines should be adopted by non-overweight people just as a matter of healthy living?

The book was written by a doctor and is evidence-based, citing only legitimate human studies (no animal studies). It debunks a lot of the commonly held beliefs around dieting and normal nutrition advice (like from the American Heart Association or the government's food pyramid). I love how the book starts off with a poignant question: Why are there fat doctors? Maybe because even many doctors have been fooled into believing the wrong thing (that gaining weight is about temptation control and the right diet as opposed to the truth: it's really about hormones, and eating more naturally and less frequently can solve a lot of problems people have).

My biggest takeaways:

Problem:
Insulin 

Solutions:
Intermittent fasting
3 meals per day, no snacks
Removing fructose and artificial sweeteners
Stress management and sleep to lower cortisol
Stop sugary drinks, juices, snacking 
Eat fiber if eating carbs

Full notes below.

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​Intro
Evidence based
No animal studies, only human
Written by doc

Part 1: the epidemic
Why are there fat doctors
Myth of calories in and out
Proximate vs ultimate cause
Not about personal choices, gluttony, sloth
Original solution was to stop eating sugary and starchy foods
Trying to stop heart disease, docs and govt started recommending low fat and high carb diet
Bad carbs (refined, sugary) are fattening, not fat
Book: pure white and deadly
Government decree to eat more carbs
“Heathy whole grain”
Counterfactual food pyramid
Adoptee studies showed little effect of environment and most effect from genetics (70%)
Thrifty gene hypothesis
Genetic predisposition to gain
Incorrect theory
Evolution favors leanness
Real cause of obesity is hormone imbalance caused by insulin

Part 2: calorie deception
Calories in and out not independent variables
Basal metabolic rate not stable
We don’t exert conscious control over Calories in
Actually hormonally driven
Fat stores are regulated
A calorie is not a calorie
Not the same
Hormones tightly regulate all systems
Starvation experiments showed that calories in affect calories out
Body balances energy budget and reduces expenditure when less consumed
Caloric reduction doesn’t cause long term weight loss
Homeostasis: adaptation to change
Hunger creates tiredness, depression, feeling cold
Vicious cycle of undereating
Limits and myth of exercise
Peter attia
Increase in exercise doesn’t affect obesity
Basal metabolic rate biggest determinant of total energy expenditure (not exercise) and it doesn’t stay stable and affected by many things including what you eat and who you are
Diet way more important than exercise
Exercise good for you but not for weight loss
Compensation: you eat more when you work out more and you do less movement elsewhere
Overfeeding paradox
Excess eating doesn’t cause weight gain. The type of food matters. Refined carbs is what creates weight gain. 
Can’t force people to eat. Really difficult to force self to gain weight. 
Key difference between individuals was metabolism
Overfeeding causes more energy exposure
Body set weight
Weight your body wants it to be
Solution is to lower body’s thermostat homeostatic set weight
Dieting is like putting in portable heater in house with AC thermostat set too low

Part 3 new model of obesity
Leptin slows fat accumulation 
Not leptin deficiency but resistance causes obesity
Insulin regulator and causes weight gain
70% of weight gain or loss purely driven by insulin
Cortisol stress hormone causes weight gain. Raises insulin. 
Long term stress causes weight gain 
Sleep deprivation causes weight gain
Low carb diet revolution with Atkins
Atkins and Mediterranean diet better than low fat
No natural satiety hormones for refined carbs because they are not natural foods
Atkins diet didn’t allow indulging in foods we love so it failed for many people after a while
Sugar much worse than other refined carbs
Not just carbs that are bad but refined ones and sugar
Insulin resistance as culprit
Obesity Time dependent
Metabolic syndrome
Vicious cycle: exposure leads to resistance. Higher doses cause more resistance. 
Pulses of hormones don’t allow resistance because not constant
Meal composition and meal timing critical
3 meals per day and no snacks
Breakfast at 8am and dinner at 6pm
Snacking and grazing bad
Need better balance between insulin dominant and insulin deficient

Part 4: social phenomenon of obesity
Snack food promoted, sponsorships
Snacking means you eat more
Breakfast most important meal to skip
Or just Small meal
Always in a rush in morning so we go to processed Foods 
Eating more fruits and vegetables should only replace less healthy foods
Replace bread with veggies
Diabesity
Poverty linked to obesity
Federal subsidies support corn and wheat for refined grains
Increased maternal weight gain leads to increased newborn weight gain and infant obesity
Stop fruit juices 
Not about exercise or playgrounds

Part 5 what’s wrong with our diet
Diabetes correlated with sugar not calories
Fructose is most dangerous sugar
Glycemic index
Natural fruit consumption much smaller scale fructose amount than high fructose corn syrup
Fructose only metabolized by liver whereas glucose by all cell
Fructose not glucose causes insulin resistance
Creates fatty liver
Remove all added sugars from diet and don’t replace with artificial sweeteners
Diet drinks bad for you 
Agave mostly fructose and not good
Stevia also bad and highly processed
Artificial sweeteners raise insulin even if don’t have calories or sugar
Glycemic index and glycemic load
Glycemic load better metric because adjusts for amount of carb in the food (watermelon vs corn tortilla)
Natural unrefined foods have low scores despite same amount of carbs
Refining disturbs balance of satiety
Harder to eat 5 oranges than drink a glass of juice from 5 oranges 
New wheat varieties less healthy
Fiber is protective when eating whole grains
Mediterranean diet with more natural fats from nuts and olive oil beneficial
Fiber: the antinutrient
Reduces absorption of other nutrients 
Soluble fiber most effective
Eating fiber with carb reduces absorption and insulin response of the carb
Natural plant foods automatically come with fiber
Problem isn’t the carbs but the high amount of processing in modern food
Fiber protects against diabetes and insulin
Vinegar also antidote against insulin
Traditional tonic for weight loss
Apple cider vinegar also has fiber
Reduces insulin resistance
2 teaspoons right before high carb meal
Adding vinegar to sushi rice
Also pickled vegetables lowers glycemic index of rice a lot
Cold potatoes with vinegar a lot better
Peanuts also reduce glycemic response
Oil and vinegar dressing reduces cardiovascular disease
Glycemic index not the goal or glucose levels; insulin levels the goal to control
New insulin index fixes that and shows there are also insulin surges in response to some protein
Insulin can increase without blood sugar
Incretin effect
Stomach digesting oral food makes more insulin than from IV infusion of glucose (counterintuitive)
Stomach is second brain
Cephalic phase
Body anticipates food before it’s in stomach
Chewing or swirling food then spitting out raises insulin
Dietary fat weakest at stimulating insulin
Dairy, meat, protein, and insulin index
Dairy biggest discrepancy: low glycemic index and high on insulin index
Whey and animal protein increases insulin a lot but creates a lot of satiety for longer
Animal protein weight gain effect larger
Dairy protein weight gain effect smaller. Low fat milk the worst. 
Protein shakes and protein bars unnatural and still stimulate insulin as before
If you are not hungry, don’t eat
Paleo diet 
No processed foods, sugars, dairy, grains, veg oil, sweeteners, alcohols
Fruits, veg, nuts, seeds, meats, herbs, seafood, eggs ok
Low carb healthy fat (LCHF): allows dairy
No bad foods, just processed ones
No protein bars
Fasting helps to cleanse
Good diet to follow
Fat phobia 
Mediterranean diet protected against heart disease
Saturated fat bad but monounsaturated fat protective
Correlation studies can’t prove causation
Need to eat a lot more omega 3 and less omega 6. Should be 1:1 ratio. 
Vegetable oils processed and not good
No association between Saturated Fat or dietary fat and cholesterol
Trans fats artificial
Protective effect of saturated fats for stroke 

Part 6 solution
Multifactorial disease
Some foods should be severely restricted and some shouldn’t 
Step 1: reduce consumption of added sugars
Check labels, dressings, sauces
Best dessert is small plate of fruits
Dark chocolate more than 70% cacao
Nuts good: macadamia, cashew, walnut, pistachios 
Dessert should be occasional not daily
Don’t replace sugar with artificial sweetener
Just don’t snack 
Stop grazing
No rice cakes
Are you really hungry or just bored
Make breakfast optional
Don’t eat sugary breakfast cereals
No more than 4g of sugar per serving
No breakfast danishes, muffins, etc
Oatmeal you have to cook like steel cut is good, lots of fiber
Many Yogurts have sugar
Avoid instant oatmeal which is heavily processed
Eggs good
Beverages: no sugar added
No dessert wine
2 glasses red wine per day fine
Best drink water with slices of lemon
Coffee healthier than thought
Tea time anytime
Green tea healthy
Bone broth healthy. Best when home made and easy to do. 
Step 2: reduce consumption of refined grains
White flour bad
Avoid processed bakery foods like muffins
Stone milled flour Best
Reduce pasta to a minimum
Enjoy carbs in whole unprocessed form
Veggies and quinoa good
Chia seeds good
Step 3: moderate protein consumption
20-30% of calories
No bars or shakes
Step 4: increase consumption of natural fats
Olive oil, butter, coconut oil
Vegetable oils worse
Mediterranean diet, high oleic
Virgin oils best
Refined oils worst
Nuts good especially walnuts
Full fat dairy best
Avocados great
Step 5. Increase consumption of protective factors
Fiber
Natural whole fruits and veggies
Flax seed
Nuts
Glucomana
Vinegar
Dipping bread into olive oil and vinegar
Fish and chips with malt vinegar
Apple cider vinegar
When to eat
To break insulin resistance, need intermittent fasts of 24-36 hours
Ancient tradition in all cultures
Naturally dont eat when sick
Improves brain function 
Key is that it’s intermittent and body can’t just get used to it
Feasting must be followed by fasting
Diets not supposed to be constant

Appendix B: fasting
Water and tea permitted
Daily 16 hour fast
Weekly 24 hour fast done 2-3 times per week
24 hour fast means skipping breakfast and lunch next day and going dinner to dinner
36 hour fast means going from dinner to breakfast on second day skipping 3 meals next day
Drink 2L water daily
8oz cool water right when day begins. Fruit infuse. 
Dilute Apple cider vinegar in water then drink it
Homemade bone broth or vegetable broth with a bit of salt
Canned broths bad
Break fast gently. Handful of nuts or small salad. 
Do it on busy work day
Natural appetite suppressors if hungry
Water
Green tea
Cinnamon. Can add to all teas. 
Coffee
Chia seeds
Can exercise and do all routines
Drink water and stay busy
Ride the waves
Don’t tell everyone u r fasting
Give yourself one month
Follow nutritious diet on non fast days
Don’t binge on Normal days
Arrange fasting schedule around normal and social life
Bone broth recipe

Appendix c: meditation and sleep hygiene to lower cortisol
Stress reduction 
Active techniques
Yoga, meditation, Tai chi, exercise
Social connectivity
Human touch
Mindfulness meditation 
Remind self of pleasant past experiences
Become aware of thoughts
Wake up in morning, have glass of cold water, and do meditation
Body, breath, and thought
Sleep hygiene
Complete darkness
Loose fitting clothes
Consistent hours
7-9 per night
See light first thing in morning
Keep bedroom slightly cool
No tv in bedroom

References
Why we get fat