Introduction Types of fats Benefits of unsaturated fats Omega-3 fatty acids Saturated fats Trans fats References Further reading
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Unsaturated fats: Unsaturated fats are considered to be healthy fats. These have various benefits, such as lowering blood cholesterol levels, improving inflammation, and preventing arrhythmia. These fats are mostly found in plant-based food such as seeds, nuts, and oils.
There are two types of unsaturated fats:
Monounsaturated fats
Polyunsaturated fats
According to the American Heart Association, Polyunsaturated fats should make up 8-10 percent of our daily calorie intake. Several studies show that replacing saturated fats with good fats (polyunsaturated fats) can significantly reduce coronary heart disease risk and improve heart health.
One study compared the effect of different diets on blood pressure and serum lipids. When a carbohydrate and unsaturated fat diet were compared, the unsaturated fat diet lowered the systolic blood pressure by 1.3 mm Hg and, among hypertensives, by 2.9 mm Hg. Additionally, the unsaturated fat diet increased the high-density lipoprotein cholesterol by 1.1 mg/dL and barely affected low-density lipoprotein cholesterol. The unsaturated fat diet also reduced triglycerides by 9.6 mg/dL. According to this study, the approximate 10-year risk of coronary heart disease was lower with an unsaturated fat diet than a carbohydrate diet.
Additionally, when saturated fats are replaced with unsaturated fats it has a beneficial effect on insulin sensitivity.
Omega-3 or n-3 fats are essential fats, meaning they can not be synthesized in the body and must be consumed as food. They are in the family of polyunsaturated fats. They are commonly found in walnuts, flaxseeds, flaxseed oils, fish, nuts, and leafy vegetables. Omega-3 fats are so important because they have a significant role in every cell wall of the human body.
There are various types of omega-3 fats; the most common one is Alpha-linolenic acid (ALA). ALA is mostly found in plant foods such as nuts, oils, and leafy vegetables. In contrast, Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are found in marine animals and fatty fish. These fats have plenty of benefits; the most notable is that they keep the heart healthy. Research suggests that people who consume seafood at least once a week have lower chances of dying from heart disease compared to those who consume seafood infrequently. Omega-3 fats also help keep in check the heart rhythm as well as lower blood pressure and heart rate.
Additionally, there is evidence that EPA and DHA may help relieve morning stiffness, swelling, and pain in patients with rheumatoid arthritis. Omega-3 fats are also important in the growth and development of a fetus and an infant. EPA and DHA play a significant role in forming the brain and nervous system. Pregnant women are advised to consume seafood frequently but should not consume fish that may have high mercury content.
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Saturated fats are beneficial when their intake is in moderation. It is mostly found in animal foods (red meat, chicken skin) and dairy products such as cream, cheese, and butter. It is also found in some tropical oils, such as coconut and palm oil.
The Dietary Guidelines for Americans suggest that less than 10 percent of the daily calorie intake should come from saturated fats. At the same time, the American Heart Association suggests less than 7 percent of calorie intake from saturated fats.
For decades it was believed that reducing the intake of saturated fats could lead to better heart health; however, this notion is being questioned. A meta-analysis was done to evaluate the link between intake of saturated fats and heart diseases (Coronary heart disease, stroke, cardiovascular disease).
The follow-up was done for 5 to 23 years of 347,747 participants. The meta-analysis of the epidemiological studies revealed that there is no significant evidence suggesting a link between the intake of dietary saturated fats and heart diseases. It is important to note that more research is needed to suggest the benefits of saturated fats.
However, the benefits of cutting back on saturated fats are dependent on which fats we are replacing them with. If replaced with good fats, it reduces the bad cholesterol and thus reduces the incidence of heart disease.
A study done in Sweden suggests that when saturated fats in the diet are replaced with unsaturated fats, it has a favorable effect on insulin sensitivity. This might even lower the risk of type 2 diabetes.
Related: Trans Fat in Food
These are considered bad fats and have a lot of harmful effects on the body. Trans fat raises bad LDL and lowers HDL. Subsequently, they are deadly for heart health. Studies show that when even 2% if calories are consumed from trans fat, it increases the risk of heart disease by 23%. Additionally, they play a role in increasing inflammation and insulin resistance.
Unsaturated fats are the healthiest fats and have several benefits. Most significant is the role it plays in heart health. Saturated fats may have some benefits when consumed in moderation, while trans fat harms overall health. The health benefits of Omega-3 fatty acids are also worth noting and must be consumed through seafood frequently.
7 healthy fats to add to your diet Play
Types of Fats. Harvard T.H Chan School of Public Health. https://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/fats-and-cholesterol/types-of-fat/
Siri-Tarino, P. W., Sun, Q., Hu, F. B., & Krauss, R. M. (2010). Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. The American journal of clinical nutrition, 91(3), 535–546. https://doi.org/10.3945/ajcn.2009.27725
Risérus, U., Willett, W. C., & Hu, F. B. (2009). Dietary fats and prevention of type 2 diabetes . Progress in lipid research, 48(1), 44–51. https://doi.org/10.1016/j.plipres.2008.10.002
Mozaffarian, D., Micha, R., & Wallace, S. (2010). Effects on coronary heart disease of increasing polyunsaturated fat in place of saturated fat: a systematic review and meta-analysis of randomized controlled trials. PLoS medicine, 7(3), e1000252. https://doi.org/10.1371/journal.pmed.1000252
Mensink, R. P., Zock, P. L., Kester, A. D., & Katan, M. B. (2003). Effects of dietary fatty acids and carbohydrates on the ratio of serum total to HDL cholesterol and on serum lipids and apolipoproteins: a meta-analysis of 60 controlled trials. The American journal of clinical nutrition, 77(5), 1146–1155. https://doi.org/10.1093/ajcn/77.5.1146
Appel, L. J., Sacks, F. M., Carey, V. J., Obarzanek, E., Swain, J. F., Miller, E. R., 3rd, Conlin, P. R., Erlinger, T. P., Rosner, B. A., Laranjo, N. M., Charleston, J., McCarron, P., Bishop, L. M., & OmniHeart Collaborative Research Group (2005). Effects of protein, monounsaturated fat, and carbohydrate intake on blood pressure and serum lipids: results of the OmniHeart randomized trial. JAMA, 294(19), 2455–2464. https://doi.org/10.1001/jama.294.19.2455
7 Things To Know About Omega-3 Fatty Acids. National Centre for Complementary and Integrative Health. https://www.nccih.nih.gov/health/tips/things-to-know-about-omega-fatty-acids
Further Reading