Fat loss is probably the most common health and fitness goal today and there are so many different products and programs designed to make people lose fat that it is virtually impossible to keep track of them all. Having different options for achieving fat loss is important, because no single approach will work for everyone, although some fat loss strategies definitely work better than others.
I hope this is obvious, but any good approach to long-term fat loss must involve making improvements in your nutrition and any product or program that promises fat loss without addressing nutritional issues is almost certainly a gimmick and a waste of money. The good news is there are many different fat loss programs that are effective. Interestingly, even though some of these programs involve very different eating habits, they often have some of the same fundamental strategies at their core.
Some of the more popular nutritional strategies involve minimizing insulin level fluctuations, eating natural (unprocessed) foods, eating small meals throughout the day etc. The multitude of nutritional strategies and diets, along with the current obesity problem, has resulted in a lot of research being done to learn more about the process of fat loss. Many studies have compared various eating strategies to figure out which ones work better than others and analysis has been done to determine what nutritional factors are most strongly linked to fat loss.
Of course, there are many factors that influence whether or not a fat loss program will be successful, but some things have been shown to be more important than others. One of the commonly studied factors is the percentage of calories consumed from fats, protein, and carbohydrates, otherwise known as the macronutrient profile. The macronutrient profile is one of the most obvious differences between nutritional programs or diets, with different programs focusing on things like minimizing carb intake, minimizing fat intake, having a balance between all three, etc.
So many programs suggest that theirs is the best for fat loss because of the particular macronutrient profile of the foods, but it turns out this is not the most important part of a meal plan, at least from a fat loss standpoint. When it comes to weight and fat loss, the number of calories consumed is more important than what type of calories you are consuming. Of course, the type of calories you consume is very important for your overall health, but eating for health and eating for fat loss are not always the same thing.
Even though the number of calories you consume is more important for weight and fat loss than the type of calories consumed, calorie consumption is still not the factor that is most strongly linked to fat loss. The single most important nutritional for fat loss is actually something called caloric density. Caloric density is a measure of how much a food weighs compared to how many calories are contained in that food. Simply stated, foods that weigh more and have fewer calories are better for fat loss than other foods.
Researchers have found that the weight of the food you eat has more of an effect on how full or hungry you feel than the number of calories contained in the food. In other words, if two people with similar appetites each eat a pound of food, they should both feel equally full, even if one person ate twice as many calories as the other person. By eating foods that have fewer calories by weight, you will be able to minimize your feelings of hunger, which is one of the keys to long-term fat loss success.
I should point out that while caloric density does not measure where the calories come from (fat, protein, carb), foods that have good caloric density scores usually have healthy characteristics. This is because many healthy components of food, such as water and fiber, have weight but do not add calories, so they will improve caloric density. On the other hand, foods that are very high in fat will have low caloric densities, because fat has more than twice the number of calories per weight than protein or carbs.
By taking a look at the things that influence caloric density, we can see that while it does not directly measure calorie content or macronutrient profiles, the caloric density of a food is essentially a partial measure of both things. Another interesting thing is that many foods with the best caloric density scores are healthy vegetables, which are considered good foods to eat on virtually every type of nutritional program or diet.
It is important to keep in mind that eating foods just based on their caloric density will not guarantee you will have a well balanced diet. You still need to include a certain amount of fat, particularly healthy fats (omega-3 oils), and quality protein if you want to achieve fat loss and good health. However, other things being similar, a person who eats foods with good caloric densities should lose more fat than a person who eats foods with poor caloric densities.
Finally I want to point out that caloric density and nutrition in general is only one component to fat loss. The most successful programs always incorporate both nutrition and exercise. Following a nutrition program that focuses on eating a well-balanced combination of foods with good caloric densities should result in fat loss, but your results will be significantly better if you consistently include challenging workouts into your routine as well.