Fat is one of the three main groups of macronutrients in the human diet, along with carbohydrates and proteins.
Fat is a major component of common foods such as milk, butter, lard, cured pork and cooking oils.
They are the main and concentrated source of food energy for many animals.
The human body can make its own fats, but there are some essential fatty acids that the body cannot make and must be obtained from the daily diet.
The importance of fats
In humans and many animals, fat serves as both an energy source and an energy store that is used when energy is needed immediately.
Each gram of fat when burned or metabolized releases about 9 food calories (37 kJ = 8.8 kcal).
Fats are also a source of essential fatty acids. Vitamins A, D, E and K are fat soluble, meaning they can only be digested, absorbed and transported together with fat.
Fats play a vital role in maintaining healthy skin and hair, insulating the body's organs from shock, maintaining body temperature, and promoting healthy cell function. Fat is also a useful protection against many diseases.
Types of fats
Unsaturated fats
Unsaturated fats are those that are liquid at room temperature. They are considered healthy fats because they can improve blood cholesterol levels, reduce inflammation, stabilize heart rhythm, and perform many other beneficial functions.
Unsaturated fats are mainly found in plant foods such as oils, nuts and seeds.
There are two types of "good" unsaturated fats:
- Mononesites Fats are found in high concentrations in:
- In olive, peanut and rapeseed oils
- In avocados
- In nuts such as almonds, hazelnuts
- In seeds such as pumpkin and sesame seeds
- Polynesians Fats are found in high concentrations in:
- In sunflower, corn, soybean and linseed oils
- In walnuts
- In flax seeds
- in the fish
- Canola oil – Although higher in monounsaturated fat, it is also a good source of polyunsaturated fat.
Omega-3 fat is an important type of polyunsaturated fat. The body cannot make them, so they must be obtained from food or supplements.
A great way to get omega-3 fats is to eat fish 2-3 times a week.
Good plant-based sources of omega-3 fats include flaxseed, walnuts, and canola or soybean oil.
Higher levels of omega-3 fats in the blood are associated with a lower risk of early death among older adults, research suggests.1
Most people don't eat enough healthy unsaturated fats. The American Heart Association says 8 to 10 percent of daily calories should come from polyunsaturated fats.
Dutch researchers conducted an analysis of 60 studies that examined the effects of carbohydrates and various fats on blood lipid levels. In tests, eating polyunsaturated and monounsaturated fats instead of carbohydrates reduced harmful LDL and increased protective HDL.2
Saturated fat
All foods that contain fat contain a mixture of some type of fat. Even healthy foods like chicken and nuts contain small amounts of saturated fat, though much less than beef, cheese, and ice cream.
Saturated fat is mostly found in animal foods, but a few plant foods are also high in saturated fat. Saturated fats are found in coconut oil, palm oil.
- Nutritionists recommend getting less than 10 percent of your daily calories from saturated fat.
- The American Heart Association recommends limiting saturated fat to no more than 7 percent of daily calories.
- However, reducing saturated fat is unlikely to have any benefit if people replace saturated fat with refined carbohydrates. Eating refined carbohydrates instead of saturated fat lowers "bad" LDL cholesterol, but also lowers "good" HDL cholesterol and increases triglycerides. The net effect is as bad for the heart as eating too much saturated fat.
The largest sources of saturated fat in the daily diet:
- Pizza and cheese
- Low-fat milk, butter and milk desserts
- Meat products (sausage, bacon, beef, hamburgers)
- Cookies and other cereal desserts
- Various fast food dishes
Although it has been argued for years that saturated fat is harmful, in recent years this idea has begun to gain traction. Several studies show that a daily diet high in saturated fat does not increase the risk of heart disease. Many are being researched, but they need to be more thoroughly systematized and refined.
The overarching message is that reducing saturated fat can have health benefits if people replace saturated fat with "good" fats, especially polyunsaturated fats.
Eating good fats instead of saturated fats lowers "bad" LDL cholesterol and improves the ratio of total cholesterol to "good" HDL cholesterol. This reduces the risk of heart disease.
Trans fats (avoid)
Trans fatty acids, more commonly known as trans fats, are produced by heating liquid vegetable oils in the presence of hydrogen gas and a catalyst. This process is called hydrogenation.
- Partial hydrogenation of vegetable oils makes them more stable and less rancid. This process also turns the oil into a solid, like margarine.
- Partially hydrogenated oils can withstand repeated heating, making them ideal for quick cooking.
- For these reasons, partially hydrogenated oils have become a mainstay in the restaurant and food industry—for baking, baking, processed snacks, and margarine.
Partially hydrogenated oil is not the only source of trans fat in our diet. Trans fats are also found naturally in beef fat and milk fat, but in small amounts.
Trans fats are the worst type of fat for the heart and blood vessels because they:
- Raises bad LDL cholesterol and lowers good HDL cholesterol
- Creates inflammation – an immune-related response – that is linked to heart disease, stroke, diabetes and other chronic diseases
- Contributes to insulin resistance
- Even small amounts can have harmful health effects—for every additional 2 percent of calories from trans fat consumed daily, the risk of coronary heart disease increases by 23 percent.
For years, only true nutrition experts knew if a certain food contained trans fat. Fortunately, after a series of scientific studies in the 1990s, a lot of information about the harmful health effects of trans fats has come to light. However, trans fat consumption is still active in many countries.
Which fats should you avoid?
Two types of fat, saturated fat and trans fat, have been found to be harmful to health. Most foods that contain these types of fat are solid at room temperature, such as:
- butter
- margarine
- beef or pork fat
Trans fats should be avoided and saturated fats should be eaten in very moderate amounts.
What fats are suitable for consumption
Doctors consider monounsaturated fats and polyunsaturated fats to be more "heart-healthy" fats. These fats are a better choice.
Foods high in these healthier fats tend to be liquid when they are at room temperature. An example is vegetable oil.
Although trans fats are the most harmful to health, saturated fats are not currently associated with an increased risk of heart disease. However, saturated fat is probably not as healthy as monounsaturated and polyunsaturated fats.
It is important to rememberthat everyone's health is individual and there is no common recipe for everyone!
So, if you want to know what nutrients your body might be lacking right now, health professionals recommend a guide – "Your Day".
- In time, pay attention to the signals sent by your well-being
- Replenish the body with natural minerals, vitamins and nutrients necessary for health.
- Enjoy energy and good mood everyday!
