Ever wondered why fats are important in our diet? Discover the types of fat, their key benefits and food sources.
Last Updated 2 Oct 2022
Although we hear a lot of negative comments about “fat”, the truth is that the body NEEDS a certain amount of fat to work properly.
Fat is part of every cell.
Excess energy is stored in the form of fats.
Fats are also necessary for the transportation and storage of fat-soluble vitamins A, D, E and K.
It supplies the body with essential fatty acids necessary for proper growth and healthy skin. Fats are a more concentrated fuel than carbohydrates and supply 9 kilocalories (38 kJ) of energy per gram.
Types of Fats
They are divided into 2 groups: saturated and unsaturated
The body obtains fat from both animal and plant sources. Although we need a certain amount of fat to be healthy, it is important to understand the kinds of fat that are most beneficial.
Unsaturated fats are a healthier alternative to saturated fat and can be found in vegetable oils such as sesame, sunflower, soy, and olive; and in oily fish such as mackerel, sardines, and salmon.
Unsaturated means that the fat is usually liquid at room temperature and generally comes from vegetable sources. Monounsaturated and polyunsaturated fats are both included in this group.
Limit your intake of these fats because high intakes may be associated with increased risk of heart disease.
Saturated means that the fat is generally solid at room temperature and is usually from animal sources.
Found in lard, butter, hard margarine, cheese and full cream milk. It is also the white fat you see on red meat and underneath poultry skin.
Did you know?
In reality, many foods contain both saturated and unsaturated fats, but they are described as one or the other depending on what they contain the most of.
So, even olive oil contains saturated fat too.
Trans fatty acids are found in various types of food, especially packaged and fried food from fast food chains as well as vegetable shortening and even some margarine.
They are formed when liquid oils such as vegetable oils are hydrogenated.
Like saturated fats, trans fatty acids also increase the bad cholesterol known as LDL cholesterol and reduce HDL or good cholesterol.
This may lead to an increase in the risk of heart disease.
Trans fatty acids are also linked to a greater risk of developing of Type 2 Diabetes.
Check food labels to minimize the intake of saturated fats and trans fats.
Some labels do not list the amount of trans fats present, so to find out, just add the values for saturated, polyunsaturated and monounsaturated fats.
If the number is less than the “total fats” indicated on the label, the unaccounted is trans-fat.
The other method is to reduce consumption of fat. Less total fat intake generally means less trans and saturated fats.
It transports fat-soluble vitamins A, D, E, and K through your body.
It contains the essential fatty acids (EFAs), which have a positive effect on the health of your heart and immune system.
It adds flavor and helps food taste good.
It is a concentrated source of energy. It keeps us from feeling hungry since fats stay in the stomach longer than other foods and are digested more slowly.
How Much Fat Do You Need?
Only 20-35% of the total body energy requirement should be provided by fats.
Excess fat in the daily diet can cause obesity, coronary heart disease and even increase the risk of certain cancers like colon and breast cancer.
At least 50% of fat intake should consist of vegetable oils rich in essential fatty acids. (1)
How About Cholesterol?
What do you think of when you hear the word cholesterol?
Many people have a negative perception of cholesterol.
They have heard that cholesterol can be bad for them and that they must avoid it.
In fact, it is found in every cell of our body.
This soft and waxy substance is produced by the liver and intestine.
Cholesterol is essential for human life and plays many important roles in the body.
It is used to form vitamin D, with help from sunlight.
It is found in large amounts in the brain and spinal cord, insulating nerve tissues.
It is used in the manufacturing of adrenal and sex hormones, like oestrogen and testosterone.
It is converted to bile acid, the substance that helps digest fats.
It also helps to “waterproof” body cells.
The liver produces enough cholesterol to satisfy these functions.
Concerns associated with cholesterol start when food intake from meat, particularly from organs such as liver and kidney, eggs, dairy and other “animal” food sources, exceeds recommended levels.
Cholesterol is not present in plant foods like fruits, vegetables or vegetable oils.
It cannot just flow loose in our water-based bloodstream.
Instead, cholesterol is transported in the bloodstream in special protein packages called lipoproteins (i.e. fat and protein complexes). There are many types of cholesterol, but the 2 major ones that we need to pay attention to would be LDL and HDL. (2)
What’s LDL Cholesterol?
Also known as low-intensity lipoprotein, it is a major cholesterol carrier in our blood stream.
If there’s an excess amount of LDL circulating in our blood, it can slowly accumulate in the walls of our arteries.
It will combine with other substances and lead to the formation of plaque, which can clog up the arteries feeding the heart and brain.
This will inhibit flow of blood to our vital organs as the artery walls become less flexible and able to adjust to the flow of blood.
This condition is known as atherosclerosis.
The formation of a clot (thrombus) near the plaque can inhibit flow of blood to part of the heart and result in a heart attack.
Similarly, if the clot is found to be inhibiting blood flow to part of the brain, it can result in a stroke.
A high level of LDL cholesterol (160 mg/dL and above) reflects an increased risk of heart disease.
That’s why the reason why LDL is considered “bad” cholesterol. Therefore, you should keep it at a low level to reduce your risk of heart disease. (3)
What’s HDL Cholesterol?
About 1/3 to 1/4 of blood cholesterol is carried by high-density lipoproteins or HDL.
Medical experts think HDL tends to transport cholesterol away from the arteries and back to the liver, either to be re-used, converted to bile acid, or disposed of in the bile.
Research has shown that HDL slows the growth of plaque by removing excess cholesterols from them.
HDL is known as “good” cholesterol since a high HDL level protects you from heart attack.
The opposite is also true: a low HDL level (less than 40 mg/dL) indicates a greater risk of health issues like stroke.
Avoid smoking since it is known to reduce HDL levels in our body. Maintaining a healthy body weight through exercise helps to promote better HDL levels. (4)
Steps To Keep Your Cholesterol Under Control
Cholesterol can be obtained in 2 ways.
The first way is from our liver which produces about 1000 mg a day though the amount may vary at times.
Another 400 – 500 mg or more can come directly from food depending on the amount of saturated fats and cholesterol eaten.
Food that is high in cholesterol is not necessarily high in fat or saturated fat, and vice versa.
Vegetable oils, for example, are 100% fat but do not contain cholesterol.
Saturated fats are the chief culprit in raising blood cholesterol levels.
The following foods are high in saturated fats, cholesterol or both: bacon fat, beef fat, pork fat, ham fat, turkey fat, chicken fat, lard, butter, cocoa butter, cream, whole egg or egg yolk, hardened fat or oil, hydrogenated vegetable oil, shortening, full cream milk and cheese.
The food you eat can have an effect on your cholesterol level.
However, some people have inherited tendencies towards high blood cholesterol levels.
They may not be able to lower their blood cholesterol, even when a low-saturated-fat, low-cholesterol diet.
If this is found to be true, their doctor may consider adding a cholesterol-lowering medicine after trying a cholesterol lowering diet.
High blood cholesterol is a risk factor for heart and blood vessel disease.
Other risk factors include a family history of heart disease, being a male, high blood pressure, cigarette smoking, obesity and diabetes.
Some of these risk factors cannot be changed while some can. The goal is to have as few risk factors as possible to lower your risk of heart disease.
Fats In The Diet: How Much Fats Is Too Much?
People with high blood cholesterol levels should reduce, but not eliminate, dietary fat.
Fats are necessary for good health, but health professionals have long observed that most diets contain too much fat, especially saturated fats.
If you are trying to reduce blood cholesterol or just want to stay healthy, you should limit your overall fat intake to 15 – 30 % or less of total calories by replacing foods high in fat or cholesterol.
If you have a condition where you are concerned about an increased risk of heart disease, diabetes or cancer, or you have difficulty maintaining your weight, you may want to reduce your fat intake towards the lower end of this range.
Eat a lot of fruits, vegetables, grains (breads, cereals, pasta, rice) and legumes (dried, cooked beans, peas and lentils), which eating small portions of lean meats, moderate portions of low-fat milk and milk products, and minimal quantities of all types of fats. (5)
Still, everyone should remember that by keeping their dietary intake of saturated fats low, they can significantly lower their dietary cholesterol intake.
A daily cholesterol intake of less than 300 mg is recommended by the American Heart Association. Folks with heart disease should go lower than 200 mg/day.(6)
Recommended Fat Intake For Optimal Health
The type of fat consumed is important.
The following ratio of saturated / unsaturated fats is recommended:
Saturated fats: less than 10% of calories (mainly in animal products such as fatty meats, butter, whole-milk dairy products and egg yolk).
Polyunsaturated fats: not more than 10% of calories (Omega-3 in fish and seafood, and Omega-6 in vegetable oils such as corn, safflower and soy bean).
Monounsaturated fats: about 10% of calories (in olive oil, peanut oil, sunflower oil, avocados).
One of the reasons for these ratio recommendations is that saturated fats seem to stimulate the formation of LDL.
Unsaturated oils appear to be helpful because they decrease total cholesterol and LDL levels.
In addition, recent preliminary studies suggest that monounsaturated fats may actually have a favourable effect on serum cholesterol and ultimately, on coronary heart disease risk.
It lowers cholesterol and LDL without affecting the good HDL.
To help you determine your desired fat intake, have your cholesterol level checked (both total cholesterol and HDL/LDL ratio).
Also, consider other risk factors such as smoking, high blood pressure, diabetes, obesity and a family history of heart disease.
Then discuss diet changes and other preventive steps with your physician.
But whether you choose 30%, 20% or somewhere in between, remember to look at your diet as a whole, over a day’s period, and not just as individual food.
For example, if you eat an ice cream, cut back on the fat somewhere else in your diet to keep your total fat intake within the guidelines. (7)
The Result of Excess Fat Intake
The body can cope with a relative small intake of excess fat.
What constitutes an excess is a debate; however, you can be sure that more than 30% of your calories from fat is an excess.
To get an excess of fat in your diet, you would have to eat junk-food and/or animal source diet.
It is not properly balanced with plant-source food.
The association between excess fat and degenerative diseases, such as vascular disease and arthritis, is definitely established.
Others include obesity, heart disease and even cancers.
Thus, moderate intake of fat (about 20-35% of your caloric intake) will at least address this issue of excess.
Eggs are high in fat.
A single egg yolk contains 186 mg of cholesterol, which is about the maximum daily intake recommended (300 mg). (8)
But, egg whites are a good source of protein. Thus, the best recommendation on eggs is to use them in moderation and where possible, use an egg white product as an egg substitute.
Fats should make up less than 35% of the total calories in your daily diet.
Based on a 2000 calories a day diet, this is about 70 grams of fat every day.
If you eat fewer than 2000 calories a day, you should eat fewer than 70 grams of fat.
Each gram of fat has 9 calories.
To find the total calories from fat – multiply the number of grams of fat in a serving shown on the label by 9.
1 ounce of potato chips has 10 g of fat
Amount of calories from fat = 90 (10 x 9) If the potato chips have a total of 150 calories, fat contributes 60% of this total (90 divide by 150).
Although the percentages may be different, all the macronutrients are equally important.
- Ward, E. M. (n.d.). Fat facts: Essential fatty acids, saturated fat, and Trans fat. WebMD. Retrieved February 27, 2022, from https://www.webmd.com/food-recipes/features/good-fats-bad-fats
- Elshourbagy, N. A., Meyers, H. V., & Abdel-Meguid, S. S. (2014). Cholesterol: The good, the bad, and the ugly – therapeutic targets for the treatment of dyslipidemia. Medical principles and practice : international journal of the Kuwait University, Health Science Centre. Retrieved February 27, 2022, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5586853/
- Hoffman, M. (n.d.). LDL cholesterol: Definition, risks, and how to lower it. WebMD. Retrieved February 27, 2022, from https://www.webmd.com/heart-disease/ldl-cholesterol-the-bad-cholesterol
- Hoffman, M. (n.d.). HDL cholesterol: “The good cholesterol”. WebMD. Retrieved February 27, 2022, from https://www.webmd.com/cholesterol-management/guide/hdl-cholesterol-the-good-cholesterol
- Mayo Foundation for Medical Education and Research. (2021, April 8). Learn the facts about fat. Mayo Clinic. Retrieved February 27, 2022, from https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/fat/art-20045550
- Krauss, R. M., Ronald M. Krauss Search for more papers by this author, Eckel, R. H., Robert H. Eckel Search for more papers by this author, Howard, B., Barbara Howard Search for more papers by this author, Appel, L. J., Lawrence J. Appel Search for more papers by this author, Daniels, S. R., Stephen R. Daniels Search for more papers by this author, Deckelbaum, R. J., Richard J. Deckelbaum Search for more papers by this author, ErdmanJr, J. W., John W. ErdmanJr Search for more papers by this author, Kris-Etherton, P., Penny Kris-Etherton Search for more papers by this author, Goldberg, I. J., Ira J. Goldberg Search for more papers by this author, Kotchen, T. A., … Terry L. Bazzarre Search for more papers by this author. (2000, October 31). Aha dietary guidelines. Circulation. Retrieved February 27, 2022, from https://www.ahajournals.org/doi/10.1161/01.cir.102.18.2284#:~:text=Although%20there%20is%20no%20precise,guidelines%20for%20saturated%20fat%20intake.
- Experts’ recommendations on fats and oils in human nutrition1. (n.d.). Retrieved February 27, 2022, from https://www.fao.org/3/T4660T/T4660T02.htm
- Mayo Foundation for Medical Education and Research. (2022, January 21). Eggs: Are they good or bad for my cholesterol? Mayo Clinic. Retrieved February 27, 2022, from https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/expert-answers/cholesterol/faq-20058468
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