As established by scientists, one gram of fat when digested in the body to the final products (water and carbon dioxide) gives energy twice as much as the same amount of proteins or carbohydrates. But completely exclude fats of both vegetable and animal origin from their diet is still not worth it. The fact is that when eating fat-containing products of animal origin, our body receives such a substance as cholesterol. Yes, the same cholesterol, which in excessive quantity has a harmful effect on the state of our health, and above all disturbs the activity of the cardiovascular system. But do not forget that this same cholesterol is one of the key components of fat metabolism in the human body. Without his participation, it becomes simply impossible to carry out some of the most important biosynthesis in our body. For example, in the absence of cholesterol, synthesis of steroid hormones is impossible, and the occurrence of such hormonal disorders, as you know, is fraught with quite serious consequences for the general condition of the body. Therefore, although the amount of animal fats in the diet should be somewhat limited, it is still not necessary to completely exclude them from the diet, even with a diet for weight loss. The only thing you can afford is to stop using fat for a very short time, for example, during the so-called "unloading day", when the main dishes on our table are products of vegetable origin or low-calorie lactic acid products.
As for fats of vegetable origin, their caloric content is as high as that of animal fats. Distinguish in appearance vegetable fats from animals quite easily: the fact is that most vegetable fats at room temperature are in a liquid state, and fats of animal origin - in a solid. But another difference, more important for our health, lies in the different physiological functions of these groups of substances. It turns out that fats of vegetable origin contain in their composition unsaturated fatty acids - linoleic, linolenic and arachidonic, which are very useful substances for maintaining our health. This is the reason for the rule of nutrition, according to which our body must provide the necessary amount of fat, not only at the expense of products of animal origin, but also due to vegetable fat-containing foods. By the way, currently in grocery stores vegetable fats are in pure form in a wide range - it is sunflower, olive, soybean and other vegetable oils. To ensure the daily needs of our body in these unsaturated fatty acids, just a couple of tablespoons of vegetable oil, which we use when preparing vegetable salads.
Thus, the necessity of the presence in our diet of fats of both plant and animal origin is quite obvious and has long been proven at the scientific level. So even with the strictest diet for weight loss, you should not completely exclude fat-containing foods from the list of foods eaten.