Well if you google ketogenic diets you will get a plethora of info...thats essentially eating as much meat and veggies you want....these diets have been used by doctors since the late 1800s to reduce obesity in patients, and it works....there are numerous studies on it....there are a lot of complicated books to read full of medical terminology, but a very simple read on the subject, which includes tons of references of these studies from 100 years ago until present, is
Why We Get Fat
Amazon.com: Why We Get Fat: And What to Do About It (9780307272706): Gary Taubes: Books
Very simple read. Not that its for athletics or bodybuilding, but please if anyone is a reader I urge you to get this since its so quick an easy read....and goes through studies comparing the whole calories in calories out thing, the stupid food pyramid stuff, and why so many doctors dont know jack shit about nutrition....all of us our different, so some of us can tolerate more carbs and stay lean as heck, but if you are crushing green veggies in addition to nothing but meat, fish, and fowl, especially considering everyone on here I am assuming trains their nuts off, takes protein shakes, and lots of BCAAs, you are not going to get fat....if you do add carbs in to all those meat and veggies, then you will spike insulin and change the entire hormonal cascade of things and get fat potentially.....but its a pain at first preparing food, and I gotta be honest I do not stick to it strictly, but I was stuck at 245lbs for nearly 8 months, doing double training sessions a day, intervals and athletic circuits in the morning and a heavier lift at night, with a long walk later at night, and stayed consistent 245lbs....I did strict meat and veggies for two weeks, dropped 12 pounds instantly, kept 2 training sessions a day, nailed an easy 375 bench, 225 for 20 reps, and deadlifted 500 for 20 reps via 2 reps everytime the clock hit a minute, so 10 minute total. For various injury reasons Im not one rep maxing, Ill tear something, my force production is higher than this old body can take...point being, I did the strict version, dropped weight, and stayed strong, as well for giggles got dunk tannked at 7.9%.
As for interval training, there also is tons of research on that...just google it....or google it along with Alwyn Cosgrove he always cites lots of research and keeps up on fat loss research, maybe Mike Boyle too....there is so much info out there and research explaining why and how intervals are a much better option than steady state cardio....