Types of Fats (good and Bad) and Their Functions

Lipids are organic biomolecules generally made up of carbon and hydrogen and, to a lesser extent, also oxygen. However, they can sometimes also contain phosphorus, nitrogen and sulfur.

The world of lipids can be a confusing field, since the terms lipids, fats, fatty acids or triglycerides can be used interchangeably even though they do not mean the same thing. In this article we will focus on fats and their nutritional significance, so we will not go into detail about other important functions of lipids, such as: structural or transport function.

Simple lipids and complex lipids

The group of lipids includes many organic compounds that basically share two essential characteristics: they are insoluble in water and they are soluble in organic solvents. In a traditional wayThey usually distinguish between simple lipids (esters of fatty acids with alcohols) and complex lipids

The most important simple lipids are triglycerides, which are usually called fats since they are stored in adipose tissue and are the main constituents of vegetable oils and animal fats, and whose function is basically energetic, although also insulating. Triglycerides are largely composed of fatty acids, for example palmic acid. Complex lipids, on the other hand, usually perform structural and functional missions.

The fact that the properties of all these substances are different means that their metabolism is also significantly different.

Functions of lipids

In general, the functions of lipids are:

In addition, lipids provide essential fatty acids for the body.

Essential and non-essential fatty acids

Fatty acids, like amino acids, can be divided into essential and non-essential The difference between these is that we must ingest the essential ones from the diet and the non-essential ones can be produced by the body. Although the essential ones are classified into families such as Omega 3 fatty acids, the best known are, for example, linoleic acid or alpha-linolenic acid.

Saturated, unsaturated or trans fats (or fatty acids)

Fatty acids, according to their chemical structure, can also be classified in different ways:

Saturated fats

All fat-containing foods are made up of different types of fat, but the amounts of each type usually differ depending on the food. For example, pork is high in saturated fat, while almonds are high in unsaturated fats (also known as healthy fats).

The fatty acids in these fats They do not have double bonds in their chain and are generally solid at room temperature The body cannot fully use this type of fat, so it accumulates in the arteries in the long run, which can cause serious health problems. That is why different organizations specialized in this topic warn that the consumption of this type of fat should be moderate.

Saturated fat increases cholesterol more than any other type of fat (except trans fat, which we will discuss later), therefore, excessive consumption can increase cholesterol biosynthesis and have a thrombogenic effect. It is found in foods of animal origin such as meat, sausages, milk and its derivatives (cheese, ice cream).

unsaturated fats

unsaturated fats They are known as healthy fats because they increase good cholesterol, they stabilize the heart rate, relieve inflammation and, in addition, provide other beneficial functions for our body. This type of fat is found predominantly in plant foods and fish.

It is possible to distinguish two types:

Trans fat

If saturated fats are harmful to the body in the long term, trans fats (transformed fats) found in hydrogenated oils and certain processed foods are even worse. Technological processes, such as hydrogenation, oil refining, etc., causes a chemical transformation in certain fatty acids, which makes them a harmful substance for our body.

Health professionals have long warned that diets high in trans fats increase beta-amyloid in the brain, which is associated with Alzheimer’s disease. Furthermore, the magazine Neurology published research that found that this type of fat is associated with brain shrinkage and an increased risk of stroke.

Other classifications of fat:

In addition to the above, fat can be classified differently:

According to its origin

Fat can also be classified depending on the source from which it is obtained and can be of plant or animal origin. Examples of animal fat are what we can find in eggs or beef; while those of plant origin are, for example, those found in nuts or olives.

According to its shape

Depending on their shape, they can be solid or liquid. The liquid ones are known as oils and the solid ones are simply known as fats. This difference can be seen with the naked eye, although it is true that the consistency of the fats can vary and have a gelatinous texture reminiscent of liquids.

This classification of fats can be done with the naked eye

According to its visibility

Finally, fat can be classified as visible or invisible. Visible fat is, for example, that found in a piece of loin, so it is possible to remove it and not consume it. On the other hand, invisible fat is, for example, that found in milk.