Nutrition 3 - fats
After a long pause, the last part of this article on nutrition is dedicated to fats.
Fats, otherwise known as lipids, are the most abundant source of energy (9,3 kcal/g). Simply put, the human body uses fat as a reservoir and source of energy which is involved in the construction of many important structures. It serves as a source for the formation of some hormones and metabolizes some vitamins in them. The issue of fat is very comprehensive so I will therefore only state here what is essential, and what everyone should know.
It is very important to know that fats are divided into saturated and unsaturated fatty acids. Animal fats are the main source of saturated fatty acids, but they are also found in palm oil and coconut oil, as well as artificially-produced hydrogenated fats (contained in many sausage products, sweets, bread and other products). The most harmful forms of all fats are trans fatty acids, which play a major role in the development of cardiovascular disease. Opposite saturated fatty acids are unsaturated fatty acids, which are contrarily very beneficial to the human organism. They participate in reducing LDL cholesterol in the blood and increasing levels of beneficial HDL cholesterol. Most cold-pressed vegetable oils (such as olive oil), nuts and fish oil are sources of unsaturated fatty acids.
Lipid metabolism is more complicated than in the case of carbohydrates and proteins and therefore takes much longer. Fatty acids can not be absorbed directly into the blood and hence the entire process enters the lymphatic system, from which they enter the blood and are then distributed to the muscles and adipose tissue. During sporting activity, fats as an energy source come into play as a last resort, when only after the exhaustion of glycogen in the muscles and glucose in the blood can fat digestion occur and only in the presence of oxygen meaning the aerobic zone must be maintained to burn fat. This is one of the reasons why, for example, there are spinning halls full of overweight people pedalling for dear life and not losing weight.
So, to summarize, excluding the inclusion of essential fats in a healthy diet would certainly be a big mistake. However, due to their high energy yield (9.3 kcal/g compared to 4.1 kcal/g in the case of carbohydrates and protein) they should not be overused and they should be sourced from vegetable oils rather than palm and coconut oils, nuts or fish. It should however be noted that this only applies to cold-pressed vegetable oils (which should also be produced cold) because as soon as the oils are used for frying etc, their double bonds break and they become harmful saturated fatty acids! As has already been mentioned, the energy value of fat is 9.3 kcal/g.
That’s it for the basics of nutrition. If you liked the article and find it useful or interesting, please share/like it. It could yield benefits to other people.
Translated by Jiří Šimonovský
