One thing to beware of is the high levels of omega-6 fats, in particular linoleic acid, that are found in conventional pork and chicken fat. Especially in America. Traditionally raised pigs shouldn't be an issue if you don't have a badly compromised metabolism. Accumulating too much can kick your metabolism into a lower gear, never mind the other issues that come with omega-6s.

Edit: Well I went and wrote a blog post I guess..

While some seem immune to this, there are a lot of former carnivores on reddit that ran into this, myself included. My story is basically:

1) I went keto, and dropped from 230 to below 180 pounds over the course of 9 months. Easiest shit I ever did.
2) Maintained that for a year. Also Easy
3) Eventually I discovered that the less fiber I ate, the better my lifelong constipation issues, and I just kinda naturally move into carnivore. Cool, right?
4) After maintaining another year, I started gaining weight again and having my depression come back. WTF

My set food rotation had a lot of fatty pork and chicken in it, which was persistently enjoyable and easy and quick to prepare (I cook everything on the stovetop, or oven). And hey, in the keto/carnivore world, animal fat is good, right? Well fuck me, when I eventually began to suspect the the metabolic effects of my food (which can be thought of as a pile of chemical signals) and took an omegaquant test I had astronomical omega-6 levels:

---------------------- | MinRef | MaxRef | Mine

Omega-6 Fatty Acids | 0.262% | 0.435% | 0.4224%

----Linoleic (18:2n6) | 0.150% | 0.304% | 0.2534%

Omegaquant tests is basically a test of blood phospholipids, I forget the specific part. It provides a snapshot of what kind of fats that are in circulation from either external intake or internal release over a recent period of time. Something like 1-2 weeks maby? Don't quote me on that. The values do not reflect the content of your stored visceral fat. Like most tests, the values don't have any inherent meaning, you have to correlate the values with how well an organism is doing.

>From https://omegaquant.com/faq/

>The reference ranges are provided simply to give an idea of how these values compare to a large number of others taken from a relatively healthy population. In the case of the dried blood spot assay, the reference range was taken from approximately 75,000 dried blood spots analyzed at OmegaQuant between 2015-2019. No information regarding the state of health of any of these individuals is known. The reference range encompasses 99% of the individuals in their respective populations. Although “average,” these are not necessarily “optimal” levels, i.e., target levels or levels that one should attempt to achieve.

That said, it's pretty reasonable that omega-6s with their pretty well established range of possible bad effects, is probably not what I want to be bumping up against the roof on. For comparison, most that took the test on reddit from what I recall seemed to be in the .30-.36 range, with only a handful above that.

So while monogastric animals seem to bio-accumulate omega-6s from their feed, ruminants seem to resist accumulation (possibly due to their large bacteria filled stomachs converting it?) despite the high omega-6 feed we give them. So I went all beef for a while, roughly the same calories. The firmer an animal fat is as room temperature, the more saturated it is, and the more resistant it is to rancidity. Pork fat can have so much omega-6 that it become soft and slimy, and can be graded lower or outright rejected by processors. My weight quickly stabilized, and my depression went away after a month. Unfortunately, like the others have found, the weight I gained sits around the gut and seems very persistent and hard to lose without prolonged calorie restriction, which itself risks lowering metabolism more.

As much as I like beef... there's no way I can just eat that. I eventually started playing around with adding carbs back, like potatoes and green apples, which I've found I can tolerate pretty reasonable amounts. Bread, beans and oats have to be limited or I get constipation issues again. I also have a fair amount of dairy, mostly cheese or sour cream. I've been able to sit at 195-200 pounds the entire time, and eventually started exercising, keeping the same weight... but at least converting stuff to muscle.