What Types of Fats Are There?

Regular consumption of trans fatty acids is considered harmful because it's capable of increasing the levels of inflammation in the body. But there are other types of beneficial fats.
What Types of Fats Are There?
Saúl Sánchez

Written and verified by el nutricionista Saúl Sánchez.

Last update: 29 March, 2021

Lipids are essential nutrients in our diet. We depend on them in order for our bodies to carry out their physiological functions normally. However, not all fats are equally beneficial. That’s why we’re going to explain what types of fats exist and their importance in the human body.

Before starting, we first need to understand that there are 3 different types of macronutrients: fats, proteins, and carbohydrates. Within each group, there’s a subdivision according to each element’s more particular characteristics, and so we can find very diverse elements here with very specific functions.

Fats as healthy nutrients

Fats are very necessary nutrients in the diet and they have many different functions. On the one hand, they help our bodies to produce energy, but they also help to maintain homeostasis since they regulate hormonal production, the immune function, inflammation, and many other functions.

Although there’s no recommended maximum intake of lipids per day, there is a minimum intake. Experts recommend that we have an intake of 1 gram of lipids per kg of body weight per day. However, we need to be more precise in this advice, because there are different types of fats and not all are the same.

On the other hand, experts advise that we don’t exceed the recommended consumption of lipids. These nutrients have a high energy density, providing 9 kilocalories per gram. It must be taken into account that a hypercaloric diet can condition weight gain, something that’s related to a worse state of health in the medium term.

Not all types of fat are the same.
Avocado is an excellent option to obtain healthy fats.

Types of fats according to their structure

We’re now going to mention the main types of fats and their importance for our bodies, as well as the position of science in this regard. To begin with, we’ll classify them according to the presence or absence of double bonds in their chemical structure.

Saturated fats

This type of lipid is characterized by not having double bonds in its structure. For this reason, they’re solid at room temperature, although sensitive to thermal variations. When a small amount of energy is applied, they transform to their liquid state.

From a health point of view, these are nutrients that have generated a lot of controversy in recent years. It was stated that its intake was harmful because it increased the risk of developing cardiovascular diseases.

However, today things have changed. According to a study published in the journal Nutrition, Metabolism and Cardiovascular Diseases , the association between saturated lipid intake and heart-related pathologies is unclear. In fact, replacing them with unsaturated fats doesn’t reduce the risk.

The truth is that its possible influence on the lipid profile has also been denied. As an investigation published in The American Journal of Clinical Nutrition explains, the presence of saturated lipids in the diet doesn’t seem to significantly influence cholesterol levels, compared to other elements such as simple sugars or the total energy balance.

Saturated fats can be found especially in foods of animal origin. Beef, poultry, eggs, and dairy stand out over other food, such as certain vegetables.

Unsaturated fats

Within this group, we have all the types of fats that have double bonds in their chemical structure. They are liquid at room temperature and have greater resistance to heat treatments. They can be subclassified into monounsaturated or polyunsaturated depending on whether they have one or more double bonds.

These types of lipids have generally been linked to maintaining good health. As stated in a study published in the journal Circulation, the regular intake of this class of nutrients significantly reduces the risk of developing cardiovascular diseases.

This is due, among other things, to their ability to reduce or modulate inflammatory levels in the body. However, to achieve this effect, it is key to maintain a controlled and balanced ratio in the supply of omega 3 and omega 6.

Both fatty acids have antagonistic effects. While omega 3 is anti-inflammatory, omega 6 behaves as pro-inflammatory.

In fact, and as can be seen in a study published in Nutrients, high intake and an equal ratio of these lipids is related to a lower risk of developing depression.

Experts often emphasize the role of the lipids of the omega 3 series in maintaining health, as can be seen in an article published in the Annual Review of Food Science and Technology.

However, this only occurs because most of the current diets have an excessive content of omega 6 with respect to them. Therefore, there’s a need to increase the presence of omega 3.

It should also be taken into account that unsaturated lipids are found in vegetable oils, nuts, and oily fish.

Therefore, the presence of these elements in a person’s diet is recommended, although you should always avoiding subjecting them to aggressive thermal processes, due to a reason that we’ll see below.

Types of fats according to their spatial configuration

Now you know how fats can be classified according to their chemical structure. But it’s just as important, or even more important, to know the differences that they can have in terms of spatial arrangement, as this can significantly condition the state of health.

Cis fats

Within the group of cis fats we find all the fatty acids, either saturated or unsaturated, that haven’t been subjected to thermal processes. In this way, all, or almost all, the lipids found in fresh foods are part of this set.

Although the concept of “good fats” was previously attributed to unsaturated lipids, and “bad fats” to saturated ones, the truth is that today this classification has evolved. All fats that have a cis configuration, regardless of the presence of double bonds in their structure, are categorized as healthy.

Trans fat

There are harmful types of fats in fried food.
It’s important to avoid fried food as it is harmful to health.

Contrary to the previous case, all the fatty acids that are subjected to aggressive thermal processes are transformed into a trans type.

Despite what we’ve said already, here there’s a significant difference between saturated and unsaturated fats. The former, due to their chemical structure, are more sensitive to heat when varying their spatial configuration.

Keep in mind that trans lipids are considered harmful to the body. They, among other things, increase the levels of inflammation in the body, according to a study published in Diabetes & Metabolic Syndrome. This favors the appearance of illnesses such as cardiovascular, metabolic, and some types of cancer.

For this reason, the consumption of fried and battered foods should be avoided. In these cases, a large amount of trans fatty acids is generated due to thermal processes, which has a negative impact on health.

Fat and cholesterol intake

Until a few years ago, the consumption of some types of fats was linked to significant alterations in the body’s lipid profile. The truth is that saturated fatty acids don’t seem to be capable of alarmingly increasing cholesterol levels in the blood.

However, trans fats do have this property. They also generate an inflammatory effect that could increase the risk of lipoprotein agglutination, which would result in the formation of atheroma plaques. In this way, they’re considered harmful to the cardiovascular system.

On the other hand, the role of unsaturated fatty acids in modulating cholesterol levels has been extensively studied. It has been possible to show a certain property in omega 3 when it comes to reducing total cholesterol and LDL, but the change isn’t significant.

The main beneficial effect comes from its modulatory capacity on inflammation.

We cannot end this topic without referring to the many questions that currently arise about the true relationship between cholesterol and cardiovascular risk.

If HDL lipoproteins were classically considered as protective, and LDL as malignant, the most recent articles are even more precise in this regard.

Modern theories suggest that the true risk would be at the level of a small fraction of the lipoprotein VLDL – a subclassification of LDL – known as oxidized VLDL. This is generated from an oxidation process of the former, induced, among other things, by a state of chronic inflammation in the body.

However, there are still many unknowns to be resolved in this regard. What does seem clear is that the intake of cis-type lipids doesn’t pose a risk to the functioning of the cardiovascular system or to health in general, and the consumption of trans fatty acids is the real concern.

Not all types of fats are healthy

As you’ve seen, it’s possible to make two classifications of the types of fats according to their spatial configuration or their chemical structure.

In this sense, it’s important for the cis-type fats to always appear in the diet, and for us to avoid the trans type. The best option of all is to guarantee variety in the diet and balance from the energy point of view.

Fats are necessary, but only in certain amounts, and always seeking to maintain the 1: 1 ratio between omega 3 and omega 6. In order to do this, the presence of oily fish and vegetable oils should be prioritized over that of beef.

Nuts can also help you achieve this dietary goal. Remember that you can always resort to supplementation, although here would you need a prescription from an expert in the field.

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