From SAD-Adaptation to Fat Adaptation
“Fat is not the problem. If Americans could eliminate sugary beverages, potatoes, white bread, pasta, white rice and sugary snacks, we would wipe out almost all the problems we have with weight and diabetes and other metabolic diseases.”
— Dr. Walter Willett, Chairman of Harvard School of Public Health, Dept. of Nutrition
It takes 3 to 12 weeks for the body to switch from:
a) merely surviving on the SAD —Standard American Diet — low in fat, but filled with sugar, to…
b) adapting to thrive on a fat-based diet.
Our ancestors preferred fat, and the genes that regulate human metabolism still express themselves optimally when we revert to burning fat as the primary energy source.
Becoming fat-adapted means higher energy levels, fewer cravings (especially carbs and sweets), and natural weight loss.
Inverting the status quo
For decades, a nutritional high priesthood led by people like Dr. Walter Willett demonized fats — especially solid animal fats — while promoting “heart-healthy” alternatives like grains and industrially-processed seed oils.
When the new, low-fat diets failed, doctors blamed obesity on overeating and prescribed Weight Watchers and impractical amounts of exercise.
I’ve been advocating eating butter for “life extension and feeling vibrant” since at least 2013.
But don’t take my word for it — read any of these mainstream outlets on the reversal of expert opinion on fat vs. carbs:
- What if It’s All Been a Big Fat Lie? (New York Times, July 7, 2002).
- A reversal on carbs (The LA Times, December 20, 2010).
- The Case for Eating Butter Just Got Stronger, (TIME Magazine, June 2016).
My friend David Clayton is one of my latest converts to a high-fat diet.
He interviewed me on his Way of Beauty Podcast (subscribe here) about my staple fats and the reasons NOT to fear healthy animal products.
A discipline not a diet
I hate using the “d word” because of the connotations with yo-yo dieting — i.e., following impossible protocols that lead to a kind of starvation followed by binging and relapse.
Instead, I like to think of high-fat/low-carb eating as a discipline.
The way off the hamster wheel is to fill up on Good Fats™ but not overeat, and adapt your body to going longer periods between meals. This resonated with David, who already practices the rigorous fasts of the eastern Catholic Church, and skips breakfast most days.
The modern world has replaced the necessity of discipline with the bizarre and unnatural concept of dieting.
The biggest barrier to becoming fat-adapted is the built up resistance to eating enough Good Fats®™©.
The second biggest is the temptation of sugary foods and carbs.
I am prone to have what my wife refers to as a “meltdown,” as I feel myself sliding down the slippery slope toward SAD-relapse:
For several hours after eating a meal high in sugar, our hormones signal to cells that energy intake (fat, carbs or protein) should be stored rather than burned.
Insulin carries excess glucose in the bloodstream to the liver, or if the liver is “full,” to adipose fat cells. Then, blood sugar crashes and we crave more sugar soon after the initial spike.
Those on very-low-carb diets try to remain “in ketosis” — i.e., avoid the insulin spikes that follow carb/sugar-heavy meals, and instead continuously convert fat into energy (whether from food or from fat stores).
While it’s possible to spike insulin without eating sugar, it’s extremely hard to do so if you are eating satiating fats.
We can contrast the endocrine or “insulin hypothesis” of obesity with the “calories in = calories out” model that urges people onto the hamster wheel of restrictive diets (eating less) and depleting exercise routines (moving more).
Once you adapt to eating fat, you are less likely to experience a constant desire to eat to maintain healthy energy levels. Cells become more sensitive to hormonal signals from insulin and leptin, and your body knows when enough is enough.
An experiment in chronometric separation
Following a strict “ketogenic” diet is difficult in a world awash in cheap carbohydrates.
Plus, there is evidence that our ancestors occasionally stumbled upon a rare starchy root or honeycomb. So while chronic carb consumption has been a disaster for modern humans, it may be adaptive to be able to switch to burning carbs intermittently.
ASIDE – one theory holds that it’s:
[carbs + fat] → “food coma” → slowed metabolism → weight gain
From an evolutionary standpoint, equal parts carbs and fat are the ideal combination for a mammal’s “autumnal diet”— i.e., stocking up on body fat so you can sleep through the winter.
I was curious to test how my body would respond to briefly switching to carbs-ONLY from my usual protocol, and then back to high fat. If my gene expression has truly been altered to make me prefer to burn fat, then this shouldn’t be a problem.
I had a perfect occasion to test this out at dinner recently. Almost everything at the table was carbohydrates (i.e., breads, pasta, starchy vegetables, and fruit).
Rather than trying to fill up on fat like I normally do, I restricted fat intake, had my fill of carbs, and then fasted until around noon the next day before returning to fat as my main macronutrient.
And guess what…
Fat alone is so satiating that it’s nearly impossible to overeat, and carbs alone are not as dense as fat (4 calories per gram compared with 9) and can be depleted rapidly if the intake is an isolated incident rather than chronic overload.
The best way to tell whether or not you’re fat adapted is to try a similar above experiment and see whether you can comfortably fast for 12–16 hours without experiencing intense carb cravings.
The reason most diets fail is they fail to satiate. You can eat to satiety on a high-fat diet and still have the flexibility of the occasional carb-rich meal. The key is to practice chronometric separation, i.e., separation of fat and carbohydrate, and generally revert to eating high fat after a period of time.
How did we get it so wrong for long?
First, the U.S. government subsidizes just 5 crops — corn, wheat, rice, soy, and cotton. Four of 5 are the main ingredients in processed junk that Americans substituted for natural fats.
Second, the old “lipid hypothesis” — the idea that fats (lipids) make you fat — made intuitive sense.
Third, “Calories in = Calories Out” is mathematically correct, but ignores the hormonal (endocrine) and epigenetic shift toward fat-burning and away from fat-storing that occur when we stick to a high-fat diet without sugar.
Finally, the endocrine-based theory takes additional explanation. 
Getting and staying in ketosis for some period of time is probably the fastest way to become permanently fat-adapted.
After 3–12 weeks you can relax your macronutrient ratios and your body will still prefer fat, while tolerating many of the more recent “neolithic” additions to the human diet, such as grains.
Resources for becoming fat adapted:
There are hundreds of blogs explaining what “keto” is (start here if you’re new to the idea), but the most helpful resources I’ve found is the Keto Contrarian’s video series with practical tips to maintain a heterodox diet in a world that is addicted to carbs:
There are even more blogs with recipe ideas — Nom Nom Paleo chief among them — although as the Keto Contrarian wisely notes, beware the scrumptious dessert substitutes that feed a sugar-addiction mentality.
Instead, stick to first principles and filling meals of meats/fats/veggies.
For my part, I’ve put together a shopping guide for a less strict version of “paleo” that can be maintained on a limited budget (both monetary and willpower).
Poor Man’s Paleo helps you leverage your resources to maximum advantage in a world that offers abundant high-quality food, but that also bombards us with less nutritious, toxic substitutes.
Finally, here are two more resources for those looking to go deeper on this topic.
1) Fat Head (movie) — almost a decade old, this spoof of *Supersize Me* fails to replicate Morgan Spurlock’s weight gain from eating nothing but fast food. It’s highly entertaining yet packs more information than some of the more scholarly works of Gary Taubes , Nina Teicholz , et. al., which have helped overturn the debunked “lipid” hypothesis.
2) The first chapter (free on Amazon!) of Sarry Fallon Morell’s *Nourishing Fats* contains a history of the “pernicious marketing effort, ongoing since 1912 [relying on flimsy evidence] to turn Americans away from nutrient-dense animal fats.” It’s a case study in the corruption of science by industry and government interests..