not really... ask a few thousand people on paleo/caveman if they restrict calories and you'll get a few thousand "no" responses.

I have eaten nothing but meat, vegetables and fat for the last several years following this random diet I found hoping to combat a skin problem. As it turns out, this diet ended up being very close to what later became the popular paleo diet, which itself is sort of a resurgance of the "caveman" from the 70s. Now, I basically follow paleo, but the first diet was reaaalllly strict. Just a ton of saturated fat, meat and vegetables. No dairy, fruit, nuts, carbs, sugar, processed food, coffee or alcohol.

This diet totally worked--my skin condition healed quickly--and I lost a ton of weight and dropped 42 cholesterol points in a few months. I totally felt good (actually happy and energetic like a kid as soon as I woke up) and it was not particularly hard to follow once my body had made the switch to running on fats, but I began to lose way too much weight after a while and it's kind of a pain to find food when you're on the go. So, after eating way more than 2,000 calories for a while in the form of fatty meat and tons of coconut oil and olive oil every day, I got a little tired of that and switched to the paleo diet which is a little more lenient about what to eat.

So, I do 5 days of the week on paleo and I often eat way more than 2,000 calories those days. I also cheat every weekend by eating pizza and ice cream or something similar. I often eat large portions of such things.

If I don't cheat regularly on the weekends I will lose too much weight, so eating a ton of calories during the week and "cheating" on the weekends works for me. I was initially 185 and now I am about 160 or 170 if I cheat a lot.