There are many low fat diets out there. Many of these types of diets are considered starvation diets as there are a very low number of calories - often below the recommended daily amount.
There are two types and it is widely understood that the saturated fats are the fats that are extremely bad for your body. These are the fats that low fat diets aim to eliminate, whilst allowing just small amounts of unsaturated fats which are actually required by the body.
Low fat diets have different degrees of how much fat they restrict from the diet. There are low fat and very low fat diets.
Most low fat diets are high in carbohydrates which in turn are supposed to help curb hunger. Complex carbohydrates are generally recommended such as whole grains, potatoes, legumes with as much fresh fruits and vegetables as desired.
Quality lean protein like from white fish, oily fish and white meat such a turkey and chicken are all good sources. Shellfish should be eaten in moderation.
Even when fat intake is low, it is still possible to eat too many calories from carbohydrates and alcohol, so the calories intake in the diet overall needs to remain low for weight loss to occur.
The best way with any diet is to prepare food yourself and try to eat as much fresh produce as you possibly can. One trap people fall into is buying food that is low fat such as pre-packaged meals, muffins, chocolate etc. The problem with these types of foods is that even if they are low in fat they are often high in sugar and the calorie content is still high.
People are under the general impression that eating a salad will result in a fat free low calorie meal. However, salads are one of the greatest offenders of masquerading as a low calorie meal. The fresh vegetables and fruit are fine, but the sauces, dressings and mayonnaise are usually high in calories. One of the worst is the Caesar Salad that can contain eggs, bacon, parmesan cheese and oils.
It is not uncommon for people to feel that it is "okay" or "rewarding" to treat themselves to a high fat or sugar product after eating something low fat. They could be eating just as many, if not more, calories then if they had just eaten a meal without concern for fats to begin with.
Though buying many foods such as sweets and pre-packaged meals that are marketed as low fat can end you up falling into a high calorie trap, there are many times where buying low fat is the way to go. Foods that are seen as basics and are likely to integrate into meals such as milk, yoghurt, butter and cheese should be low fat options. These are also the types of foods that you can be safe will not be high in calories. It will require to a degree some education on the part of the dieter. They will need to learn read labels on pre-packaged foods to establish the fat and sugar content. As people read labels and become more familiar with the nutritional value of foods in general, they will gradually learn to eat out and order foods that are low fat without hidden calories like sugar.