It’s a mistake that keeps getting repeated by the fitness savvy folk entering the carnivore landscape. At this point, fat phobia has been stamped into the cultural consciousness, and while the low fat crusade has waned from its peak in the 1980s, it still plays a defining role in nutritional dogma. Which is why we have carnivore recruits attempting the diet with chicken breast, 5% mince, and having a terrible time of it.
So if you’re about to take the plunge and replicate the ancestral diet, take this as a warning. You can have your protein, but it needs to be matched with copious amounts of fat. Humans didn’t spend millions of years of evolution to end up with grilled chicken breast.
Protein Vs Fat
The truth of macroeconomics is, a meat-only diet is devoid of carbs and therefore in need of an alternative energy source.
Protein can’t fill that function, since it can’t be metabolised quickly, and is needed for other critical duties such as repairing and building your body’s tissues. They also don’t have a form of energy storage, like carbohydrates have with glycogen, and fats have with body fat. If you can’t use the protein you’ve ingested for the day, it gets wasted.
To make matters worse, protein breaks down into toxic nitrogen, and the rate at which the body can clear it is capped at around 35-50% of total calories. The absolute maximum translates to around 4.4 grams of protein per kg of bodyweight. You might be able to eat more than that, but it’ll be a tedious experience, and you won’t utilise that bonus protein.
That’s why the body will only use amino acids as energy when carbs and fats are insufficient.
In such situations, they’ll also be borrowing some of those aminos from your own muscle proteins. Basically, you’ll end up cannibalising yourself.
Fats, on the other hand, can be stored in near infinite amounts, and have no such limits on how much can be metabolised for energy.
Compared to carbohydrates, fat still provides far greater storage capabilities, and a slower breakdown that allows a steady stream of energy across the day.
As the clincher, fatty acids can be further broken down into ketones, which have their own set of magical properties that quell stress, suppress appetite, and streamline the mitochondria. Fats are simply the superior energy source.
Is High Protein Low Fat Ancestral?
If we can prove that our ancestors at a high protein low fat diet across our paleolithic evolution, then it would logically follow that we would be well-adapted to eat a high protein low fat diet.
Unfortunately, there’s no such precedent to borrow from.
Our ancestors specialised in hunting large mammals. Typically, the bigger the animal, the larger their fat percentage is. Now you might argue that deer and horses are quite lean. And you’d be right, except they weren’t frontline features on the paleolithic menu.
2.5 million years ago, the average weight of a non-flying terrestrial mammal was 500kg. In modern times, it’s down to 10kg. The paleolithic landscape was dominated by the megafauna, large herbivores like the mammoth, woolly rhinoceros, and giant ground sloth. Over the ensuing years, those gigantic creatures were ground into oblivion, driving our ancestors into compromising with smaller and smaller prey.
Smaller prey, like deer, were simply less enticing for humans. They carried fewer calories, smaller fat reserves, and were much harder to track and hunt. Try finding and taking down an elk with a spear, and let me know how that goes. A megafauna like the woolly mammoth, on the other hand, wouldn’t exactly be subtle.
You’d know if there was one within ten miles of your little hideout on the steppe. A mammoth would leave large hoofprints, wreck anything in its path, and could be easily herded into a pitfall that your crew had dug and covered the day before.
Once that mammoth had been trapped and stabbed to death, it could provide enough meat and fat to keep your tribe going for months. Which might seem unusual since freezers were only invented in the last century, but humans are actually specifically adapted to eat rotting carcasses. That’s why our stomach acidity is on the level of scavengers. It’s acidic enough to tear apart all the pathogens that might arise in fermented meat.
And to add to that, it was colder back then.
The fat itself didn’t just provide greater yields in the form of calories, it enabled our ancestors to store enough bodyfat to survive the barren weeks that would have often taken place between successful hunts. Without the ability to stock up on body fat, chances are we’d have been wiped out ourselves by the relentless winters.
So as long as the megafauna were around, the deer and the horses could gallop around with little care for the world’s most dangerous predator. But once the megafauna got taken out the game by overhunting, they were put under the crosshairs of a species that was getting increasingly capable of hunting smaller prey.
Unfortunately, with the decline in available fat due to smaller prey size, humans ultimately had no choice but to begin performing some form of agriculture. Some became pastoralists, domesticating animals for their meat and milk. Others adopted farming, using carbohydrates from grain to buffer the lack of animal fat.
In shorter words, a low carb, low fat, high protein diet simply wasn’t sustainable for our paleolithic ancestors. That ultimately played a huge role in commencing the first agricultural revolution, and the slow death of the hunter gatherer lifestyle.
That’s because protein simply couldn’t be relied on as an energy source, since humans couldn’t efficiently metabolise higher doses. This left us with the choice of fat or carbs to do the heavy lifting. The fat reserves ran out as the megafauna were hunted into extinction, and an alternative had to be found. The rest is, literally, history.
Finding The Perfect Fat To Protein Ratio
What is the implication of all this? Given that we know protein has an energy cap, and that our ancestors were highly unsuccessful at following a low carb, low fat, high protein diet, it follows that trying to replicate that with carnivore would be a terrible idea.
That means you don’t want to let your fat to protein ratio get too low. If it does, you’ll be more likely to encounter unwanted diet hang-ups like nagging hunger and low blood sugar.
A lack of fat will also reduce your body’s ability to produce enough ketones to maintain a strong state of ketosis. That will in turn force you to rely more on gluconeogenesis for energy, which is the rate limited breakdown of protein to glucose that won’t get you firing on all cylinders.
That being said, protein is still a critical macronutrient that you can’t afford to slice too low, since it’s partly responsible for preventing muscle breakdown across a sustained deficit. Which is the single worst thing you can achieve on a diet. You lose muscle, your metabolism drops with it, and it won’t recover until you regain that lost mass.
Keeping the fat to protein ratio at around 1:1 by the gram is a safe bet for providing the body with plenty of energy in the form of fat, while maintaining enough protein to safeguard against muscle breakdown.
This isn’t a golden rule for those seeking out the optimal form of carnivore, but it makes for a pretty good guess.
2:1 Fat To Protein Ratio
There are people who ramp their fat intake up to 2:1, and find it the best fit for its ketogenic potency. For me, it was a step too far. My digestion couldn’t handle that fat load while keeping calories in bulk mode. To reach 2:1, I was forced to pump up the fat count through rendered fats like butter and tallow. This often led to brain fog that sometimes persisted for hours after meals.
Dipping Below The 1:1 Fat To Protein Ratio
On the other hand, taking it below 1:1 spiked my cravings and turned me into an insomniac, albeit during a deficit. Relying too much on protein to prop up a bulk also just resulted in me failing to force feed my way through four pounds of beef.
There might be situations where you’d be forced to go to 0.5-0.8:1, such as trying to whittle off the last slivers of abdominal fat at the end of a cut. At that point, it might be the only way you can drop the calories lower to counter the metabolic suppression of a sustained energy deficit. Even then, I’d save that hail mary for a short 2-3 week stint, otherwise it’s likely to overstay its welcome.
The ideal fat to protein ratio is still going to be somewhat individual, as some will be better at metabolising higher ranges of protein, especially those who are experienced lifters who’ve regularly dabbled in high protein diets. But I’d still hazard the guess that they’d see even better results by tweaking the ratio further towards fat dominance.
Borrowing From My Current Routine
I’ve always found ranging between 1:1 and 1.5:1 to be the right match, regardless of the quantity of food I was having. Right now I’m gaining weight while eating 5000 calories with 419 grams of fat, and 284 grams of protein. That puts me at a fat to protein ratio of 1.47. I pick meats that contain a 1:1 ratio, then add some heavy cream in the mornings while my fat digestion is at its best.
That 284 grams of protein makes up just 23% of my total calories, which is comfortably below the top end of protein absorption. Technically, it’s a high protein diet, but I’m very fuelled by fat.
Carnivore is by definition, a high fat diet. That’s how our ancestors ate, and that’s how our body’s are designed to run. So if you still have the aversion to fat drummed into your brain, please fight past it. Ditch the chicken breast, and load up on brisket, eggs, pork belly, with a healthy side of heavy cream. Give the system what it craves.