The best way to avoid a high-fat diet is to abstain from all animal products. "Extra-lean" ground beef provides about 54% of its calories in the form of fat. 51% of the calories of a roasted chicken come from fat, as do 40% of the calories of salmon. By contrast, less than 1% of the calories of a potato come from fat. As long as you don't consume the potato in the form of french fries (which can increase it's fat content by more than two hundread times!), or top the potato with cheese, butter, or sour cream, it's an excellent low-fat food. Steamed or baked, topped with ketchup (look for organic brands, made without white sugar) or salsa or parsley or low-fat mushroom sauce or eaten plain, potatoes are a fine choice if you're watching your waistlines. In place of animal foods, choose any complex carbohydrates - fruits, vegetables, grains or beans - and they will help make you or keep you slim. Salads are good choices, as long as you don't pour high-fat dressing on them.
Eating a low-fat diet also means avoiding or limiting your intake of vegetable oils, margarine, nuts, seeds, olives, and avocados. Even a vegan diet may not hlep you lose weight, or lower your blood cholesterol levels, if you replace meat with large helpings of peanut butter, fried vegetables, white bread smothered in margarine, pasta soaked in olive oil, doughnuts, and potato chips.