"I'm no expert in this field, this is my science, it's what works for me," he told the Daily Telegraph.
"Others might try it and say, 'It's not for me'.
"I've been on the carnivore diet for eight months, before that I wasn't a full vegan but I was trying to eat healthy like that, trying to stay low on my meat and eat more veggies, no dairy.
"But I felt like I got quite lean but also soft in my muscles. Although I was training really hard, anytime I'd take contact I'd find I was getting hurt.
"Now I've combined this diet with pre-hab, looking after my body before I get on the field, before I leave the house, that has been a game-changer.
"The way I feel physically and mentally right now, it's much better than 2016 or 2017. It's a good feeling to know the things you're doing and put time and effort into are paying off.
"This is just how I eat now."
Cooper is currently contracted to Japanese rugby side Kintestu Liners, however the Top 14 is on hiatus due to Covid-19.
"It's like any diet, people are going to have their opinions. That's what I say to a lot of the boys that ask me about diet, I'm in no place to be giving advice, this is just what I do, and what works for me," Cooper told the Daily Telegraph.
"I've been in professional sport for 15 years, I've gone through stages where I'm only eating what our dietician says and I didn't feel great, feeling bloated and getting reflux.
"I've tried being vegan three times a week, vegetarian three times a week, tried eating normal, then I've gone no carbs, I've played around with certain things and found out what's worked best for me at the moment.
"I've really enjoyed the benefits of this meat diet. It does seem strange to a lot of people because what we're told is normal — 'eat vegetables otherwise you can't digest your food' — I've had no problems whatsoever."
Quade Cooper's daily menu:
7am: Bulletproof coffee (2 cups of coffee, 2 tablespoons of butter, 1 tablespoon of MCT oil)
9am: Sip bone broth throughout workout
10.30am: Two rib-eye steaks with salt and butter
6pm: 800 gram tomahawk steak with roasted bone marrow, a dozen oysters.
