Cygirl:
High fat diet aside, it's simply hard to keep fat below 40%, if you get at least 100-120g of protein from leanest animal source (skinless chicken breast, lean red meat, etc.), 1-2 boiled eggs, and a bit of olive oil (1tbs) with your salad. Simply put, try to meet RDA requirements and keep your calories in reasonable range, and your carbs lower, and you wil get more fat than food pyramid allows anyway. This is even not counting nuts, adocado, and fatty fish like salmon and tuna. So, unless you are eating salad with vinegar only, egg whites, cod fish and such, you will get at least 40% of your calories from fat. So, it's a trade off, either keep your fat super low or your carbs (15%), since your protein intake should support lean body mass and remain the same reagrdless of the diet. Simply take your pick. But remember, you can't have it both If the idea of eating 6 eggs dripping in lard is not appealing (I am not sure who can eat 6 eggs at once ), then simply eat salmon, sardines, advocado, seeds and nuts. You will get lots of heart friendly Omega-3, and less saturated fat. When it comes to high fat diet, think low fat in reverse. Remeber low fat craze, it was recommended to keep fat intake <20%, even better 10-15% of your total calories. So, it's the same with carbs. Both, fat and carbs are sources of energy, carbs being fast burning fuel, while fat burns slowly. All LC diets are based on the same premises: burn fat instead of glucose. Protein is not a fuel, however, can be turned into glucose, if eaten to excess.
As with everything, YMMV on any diet, it's just a matter of preferances.
JMHO.
D.