Paleo Leap http://paleoleap.com/paleo-diet-faq/
does a fabulous job of explaining briefly why we should choose Paleo. Please stop by there site and take a look. Below is an excerpt from their site describing fat and calorie intake when following the Paleo diet.
How much fat, proteins and carbs should I eat?
This is the million dollar question and it’s certainly very understandable that one would like to get and follow a magic ratio of carbs, protein and fat.
Unfortunately (or fortunately), there is no magic number to give and everyone promoting the Paleo diet will promote something slightly different or a range to play with.
This makes sense because we all have different needs in relation to our health condition, personal preferences, fitness condition and goals. Our ancestors also ate various macronutrient levels depending of the food available, the preferences and the climate. For these reasons, a one size fits all diet in terms of macronutrients like fat, protein and carbohydrate is probably not a good idea.
The simplest way to do it is to eat what feels natural while including lots of healthy animal fat, animal protein and vegetables as well as some optional fruits and nuts. What we like to promote is to eat high fat, moderate protein and low to very low carb (focusing on vegetables). Carbs, in the form of vegetables, fruits and tubers can be eaten in larger quantity by someone who tolerates them well or who needs the energy for long distance and endurance sports. Higher carbs, even from natural sources, are often the cause of difficulty losing fat or to healing from an autoimmune disease, and people suffering from those or who are already insulin resistant from their previous diet could benefit from having minimal amounts of carbs.
Even zero carb can prove to be very beneficial when you take care to eat high quality meat, lots of fat, fish, and organs, and cook with bones (stocks and marrow). It can be a real lifesaver when trying to heal a damaged gut, but shouldn’t be followed just to feel “pure” about not eating carbs like some vegetarians do about not eating meat.
If we take Mark Sisson’s carb recommendations, which are very reasonable, one could eat between 100 and 150 grams of carbs per day for maintenance, between 50 and 100 grams for moderate fat loss and less than 50 grams for accelerated fat loss. You’ll see that 150 grams of carbs represents a lot of fruits and vegetables, enough to satisfy those who dislike the idea of a very low carb diet.
As for proteins, the recommendations vary between 0.7 grams per pound of lean body weight mass per day to 1g of total body mass per day. On the low end, an individual who weighs 180 pounds and has a lean body mass of 160 pounds would eat around 112 grams of protein per day and 180 grams a day in the high end of the recommendation. Those recommendations take into account preservation and gain of lean muscle mass. We would say that if you fall anywhere between this range, you are in the sweet spot for your daily protein need.
As for fat, you should probably have as much as you want and it should be your main macronutrient intake. One easy strategy is to cover your bases in terms of protein and carbs and consume the rest of your calories from fat. Eat until you’re not hungry anymore and don’t count calories.
With all that being said, we want to reiterate the importance of not stressing over macronutrient intake. Don’t start calculating everything. Unless you’re dealing with a specific problem, the Paleo diet should be all about simplicity and flexibility.