What is the role of fats in nutrition? Surely, a much discussed issue that can be confusing. Saturated, poly-unsaturated, Ω3, Ω6, trans, lots of kinds of fats, many scientific names , a lot of information, opinions, but one thing is certain. Fats are very fatening! They are however inevitable in our diet and sometimes even necessary. That’s why we have to understand their properties, in order to make the right choices in our daily life.
Lets start by dividing fats into groups, and explaining the main differences between them.
High consumption of saturated fats has been connected with cardiovascular deseases, and the increase of blood cholesterol. Therefore, doctors suggest that we should avoid them as much as possible. The main sources of saturated fats are animal products, and some vegetable ones such as oils or butters derived from palm seeds. Hydrogenated vegetable fats fall also in this category.
Unsaturated fats (or fatty acids) are mainly present in vegetables, seeds and fish. Their consumption reduces “bad” cholesterol (LDL) and increases the levels of “good” cholesterol (HDL).in our blood stream. They therefore contribute to healthy blood vessels, they keep them elastic preventing cardiovascular desease. In addition, their benefits include the improved brain function, and the general feeling of well-being. They are considered as “essential” because despite the fact that they are necessary for or bodies functions, we rely 100% on our food for their intake. Unsaturated fats are divided in two categories:
One of the main sources of mono-unsaturated fatty acids is olive oil. For many, this is the reason that people living in the meditteranean countries have a lower risk of heart desease. Other good sources are avocados, as well as some seed oils.
Poly-unsaturated faty acids include Ω-6 fatty acids (sources: nuts, whole grain cereals), and Ω-3 fatty acids (sources: soy beans, lineseeds, fatty fish, sardines, salmon, etc). Their frequent consumption is absolutely necessary as we completely rely on these kind of foods for their intake.
Having made these basic distinctions, it is easier to understand if the kind of fat in our food belongs to the more or less beneficial kinds.
Regradless of this however, all fats have a lot of calories. 9 calories (kcal) per gram, compared to 4 kcal per gram of proteins and carbohydrates. This means that even the best or more beneficial kinds of fats (olive oil, poly-unstaureted, etc) have more than double the calories for every gram we consume compared to proteins and carbs. So, if you are worried about your calory intake you have to be very careful.
Have a look at the following interesting fact:
Looking at the nutrition tables of foods we buy, you will notice that contents are measured in percentages (%) of their weight. For example, 100gr of the product may contain of 45% carbohydrates, 3gr proteins and 10gr fo fats. This is presented as 10% fat content. Yes 10% fat content but in weight. If we translate it in calories, the picture changes completely. As each gram of fat is equal to 2,25 times the calories in proteins or carbs, this means that the percentage of calories coming from fats of this product is over 22%.
This opens another big chapter in nutritional habits, that is proper reading of nutritional labels. This will be discussed in an other article of our blog, later on.
– Yes, there are beneficial fats, fats necessary for proper body functions. We have to get to know them in order to make the right nutritional choices.
– Due to their high calrie content, we have to be very careful when it comes to quantity of fatty foods we consume.
– Pay special attention to nutritional labels of packaged foods. They refer to the content percentage measured in weight, not in calories! If a product has a 10% fat content in weight, this means over 22% fat content in calories.
Let’s get more familiar with fats. They are not necessarily our enemies. They are everywhere, and they are necessary. All we need to do is get to know them better.