The Fat Facts: Unpacking Dietary Fats for a Healthier You

Dietary fats often get a bad rap, with many people equating “fat” with “unhealthy.” However, fats are essential macronutrients that play critical roles in our bodies. From providing energy to supporting cell growth, protecting our organs, and helping our bodies absorb certain nutrients, fats are vital). But not all fats are created equal. In this article, we’ll dive into the different types of dietary fats, distinguish the “good” from the “bad,” explore their various sources, and discuss their impact on health.

Understanding Dietary Fats

Dietary fats are divided into four main categories: 

1. Saturated fats
2. Trans fats
3. Monounsaturated fats
4. Polyunsaturated fats

Each type has different effects on health, and knowing the difference can help you make better dietary choices. Let’s explore each type in more detail. 

Saturated Fats

Saturated fats are typically found in animal products such as meat, butter, cheese, and other dairy products. These fats are solid at room temperature and are known for their distinctive texture and flavour, which is why they are often used in cooking and baking. Beyond animal products, saturated fats are also present in some plant oils like coconut oil and palm oil. These plant-based saturated fats have unique properties and benefits, such as providing a stable cooking oil that can withstand high temperatures without breaking down (American Heart Association, n.d.).

For many years, saturated fats have been associated with increased levels of LDL (low-density lipoprotein) cholesterol in the blood, which can raise the risk of heart disease (American Heart Association, n.d.). LDL cholesterol, often referred to as “bad” cholesterol, can contribute to the buildup of plaques in the arteries, leading to atherosclerosis, a condition that can result in heart attacks and strokes (National Heart, Lung, and Blood Institute, n.d.). This has led to widespread dietary recommendations to limit the intake of saturated fats in favour of unsaturated fats (U.S. Department of Health and Human Services, 2015). However, recent research suggests that the relationship between saturated fats and heart disease is more complex than previously thought. Some studies have indicated that not all saturated fats have the same impact on health, and the effects can vary depending on the specific type of saturated fat and the overall dietary context (Siri-Tarino et al., 2010). For example, dairy fats, which contain a mixture of different types of saturated fats, may have a more neutral or even beneficial effect on heart health compared to saturated fats from processed meats (Dehghan et al., 2018).

The role of other dietary factors, such as the presence of refined carbohydrates and sugars, is becoming more apparent in the context of heart disease risk. Replacing saturated fats with highly processed carbohydrates does not seem to provide the same cardiovascular benefits as replacing them with healthy unsaturated fats (Harvard T.H. Chan School of Public Health, n.d.). This has led to a more nuanced understanding of dietary recommendations, emphasising the importance of overall dietary patterns rather than focusing solely on reducing saturated fat intake (Astrup et al., 2011).

It’s also worth noting that saturated fats play important roles in the body, including being a component of cell membranes and a precursor for certain hormones (U.S. Department of Agriculture, 2020). Therefore, completely eliminating saturated fats from the diet is neither practical nor advisable. Instead, a balanced approach that includes moderate consumption of saturated fats within the context of a diverse and nutrient-rich diet is recommended.

Trans Fats

Trans fats are a type of unsaturated fat that can be found in two forms: naturally occurring and artificial. Naturally occurring trans fats are found in small amounts in some meat and dairy products, produced in the stomachs of ruminant animals like cows and sheep. However, the primary concern regarding trans fats comes from artificial trans fats, which are found in partially hydrogenated oils. These oils have been widely used in many processed foods such as baked goods, snacks, fried foods, and margarine due to their ability to enhance flavour, texture, and shelf life. The process of creating artificial trans fats involves hydrogenation, a chemical process that adds hydrogen atoms to liquid vegetable oils, converting them into a more solid form. Hydrogenation increases the stability of oils, making them less likely to spoil and more suitable for high-temperature cooking. This process involves heating the oil and exposing it to hydrogen gas in the presence of a catalyst, typically a metal such as nickel. As a result, the oil becomes partially hydrogenated, forming trans fatty acids with a structure that is not naturally found in most foods. Hydrogenation alters the chemical structure of the fat (Harvard T.H. Chan School of Public Health, n.d.). This structural change transforms the oils into semi-solid or solid fats, which can withstand higher cooking temperatures and have a longer shelf life. The resulting trans fats are found in a variety of processed foods, contributing to their desirable taste and texture.

Despite their functional benefits in food production, trans fats are widely considered the worst type of fat for your health. They have been shown to not only raise levels of LDL (low-density lipoprotein) cholesterol, often referred to as “bad” cholesterol, but also lower levels of HDL (high-density lipoprotein) cholesterol, known as “good” cholesterol (American Heart Association, n.d.). This dual impact significantly increases the risk of heart disease, stroke, and type 2 diabetes. High levels of LDL cholesterol can lead to the buildup of fatty deposits in the arteries, known as atherosclerosis, while low levels of HDL cholesterol reduce the body’s ability to remove LDL cholesterol from the bloodstream (National Heart, Lung, and Blood Institute, n.d.).

The adverse health effects of trans fats have prompted many countries to implement regulations to reduce or eliminate them from the food supply. These regulations include mandatory labelling of trans fats on nutritional information panels, restrictions on the use of partially hydrogenated oils in food production, and outright bans on trans fats in certain jurisdictions. For example, in 2015, the U.S. Food and Drug Administration (FDA) determined that partially hydrogenated oils were no longer “generally recognised as safe” for use in food, leading to their gradual removal from the U.S. food supply (U.S. Food and Drug Administration, 2015). Efforts to eliminate trans fats have led to the development of alternative fats and oils that can provide similar functional properties without the associated health risks. This includes fully hydrogenated oils, which do not contain trans fats.

In summary, trans fats, especially those found in partially hydrogenated oils, pose significant health risks due to their impact on cholesterol levels and overall cardiovascular health. The process of hydrogenation, which creates these fats, has been widely used in food production but is now being phased out in favour of healthier alternatives. Reducing trans fat consumption is a critical step in promoting heart health and reducing the incidence of diet-related diseases (American Heart Association, n.d.).

Monounsaturated Fats

Monounsaturated fats are a type of unsaturated fat that is beneficial for overall health, particularly cardiovascular health. These fats have one double bond in their chemical structure, which makes them more stable than polyunsaturated fats but still liquid at room temperature. They are found in a variety of foods and oils, including olive oil, avocados, nuts such as almonds, peanuts, and cashews, and seeds like pumpkin and sesame.

One of the primary health benefits of monounsaturated fats is their ability to improve blood cholesterol levels. Specifically, they can help reduce levels of LDL (low-density lipoprotein) cholesterol, often referred to as “bad” cholesterol, which can lead to the buildup of plaques in the arteries and increase the risk of heart disease and stroke. At the same time, monounsaturated fats can help maintain or even increase levels of HDL (high-density lipoprotein) cholesterol, known as “good” cholesterol, which helps remove LDL cholesterol from the bloodstream (American Heart Association, n.d.).

The heart-healthy benefits of monounsaturated fats have been well-documented in scientific research. For example, studies have shown that diets rich in monounsaturated fats, such as the Mediterranean diet, are associated with a lower risk of cardiovascular diseases. The Mediterranean diet emphasises the consumption of olive oil, a rich source of monounsaturated fats, along with fruits, vegetables, whole grains, and lean proteins. This dietary pattern has been linked to lower rates of heart disease, reduced blood pressure, and better overall health (Estruch et al., 2013).

Incorporating monounsaturated fats into your diet can also have additional health benefits beyond cholesterol management. These fats can help improve insulin sensitivity, which is important for blood sugar control and can reduce the risk of type 2 diabetes (Esposito et al., 2010). They also have anti-inflammatory properties, which can help reduce chronic inflammation in the body, a contributing factor to many diseases including heart disease, cancer, and arthritis (Estruch et al., 2013). Monounsaturated fats also play a crucial role in the absorption of fat-soluble vitamins such as vitamins A, D, E, and K. These vitamins are essential for various bodily functions, including vision, bone health, immune function, and antioxidant protection (Harvard T.H. Chan School of Public Health, n.d.). By including sources of monounsaturated fats in your meals, you can enhance the absorption of these important nutrients and support overall health.

To reap the benefits of monounsaturated fats, it’s important to make mindful dietary choices. Here are some practical tips for incorporating more monounsaturated fats into your diet:

• Use olive oil as your primary cooking oil and for salad dressings.
• Add avocados to salads, sandwiches, and smoothies.
• Snack on a handful of nuts such as almonds, peanuts, or cashews.
• Include seeds like pumpkin and sesame in your meals and snacks.
• Opt for nut butters as spreads or ingredients in recipes.

By making these simple dietary adjustments, you can enhance your intake of monounsaturated fats and enjoy their numerous health benefits. Remember that while monounsaturated fats are heart-healthy, they are still fats and should be consumed in moderation as part of a balanced diet. 

Polyunsaturated Fats

Polyunsaturated fats are another type of healthy unsaturated fat, characterised by having more than one double bond in their chemical structure. These fats remain liquid at room temperature and are found in a variety of plant and animal sources, including vegetable oils like soybean, corn, and sunflower oil, as well as fatty fish such as salmon, mackerel, and trout. Polyunsaturated fats are especially important because they include essential fatty acids that the body cannot produce on its own: omega-3 and omega-6 fatty acids. These essential fats must be obtained through the diet, and they play critical roles in maintaining overall health.

Omega-3 fatty acids are a group of polyunsaturated fats that have been extensively studied for their numerous health benefits. The three main types of omega-3 fatty acids are:

1. Alpha-linolenic acid (ALA), which is found in plant sources such as flaxseeds, chia seeds, and walnuts
2. Eicosapentaenoic acid (EPA), which is primarily found in fatty fish and algae
3. Docosahexaenoic acid (DHA), which is also found in fatty fish and algae

Omega-3 fatty acids are particularly renowned for their numerous health benefits. These essential fats play a crucial role in brain function, supporting cognitive development and maintenance throughout life. Omega-3s are also known for their powerful anti-inflammatory properties, which can help reduce the risk of chronic diseases such as heart disease, arthritis, and certain types of cancer. Additionally, omega-3s have been shown to support heart health by reducing triglyceride levels, lowering blood pressure, and preventing the formation of blood clots (National Institutes of Health, n.d.). Sources of omega-3 fatty acids include fatty fish, flaxseeds, chia seeds, walnuts, and algae-based supplements. The three main types of omega-3s are alpha-linolenic acid (ALA), found in plant sources, and eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), found in marine sources. Incorporating a variety of these foods into your diet can help ensure you receive an adequate amount of omega-3s to support overall health (Harvard T.H. Chan School of Public Health, n.d.).

Omega-6 fatty acids, on the other hand, are also essential for health but must be balanced with omega-3 intake. These fats play a role in brain function, growth, and development, and they are involved in maintaining healthy skin and hair, regulating metabolism, and supporting the reproductive system. However, omega-6s can promote inflammation when consumed in excessive amounts, which can contribute to chronic diseases such as heart disease, diabetes, and arthritis. It is important to maintain a proper balance of omega-6 to omega-3 fatty acids in the diet to optimise health outcomes (National Institutes of Health, n.d.). Common sources of omega-6 fatty acids include vegetable oils like soybean, corn, and sunflower oil, as well as nuts and seeds. To achieve a healthier balance, it is recommended to increase the intake of omega-3-rich foods while moderating the consumption of omega-6-rich foods.

In addition to their specific health benefits, polyunsaturated fats can help improve cholesterol levels by lowering LDL (low-density lipoprotein) cholesterol, often referred to as “bad” cholesterol, and raising HDL (high-density lipoprotein) cholesterol, known as “good” cholesterol. This can reduce the risk of heart disease and stroke. Polyunsaturated fats also support healthy cell membrane function, enhance the absorption of fat-soluble vitamins, and play a role in hormone production.

To incorporate more polyunsaturated fats into your diet, consider these tips:

• Use vegetable oils like soybean, corn, and sunflower oil for cooking and baking.
• Include fatty fish in your diet at least twice a week.
• Add flaxseeds, chia seeds, and walnuts to your meals and snacks.
• Consider omega-3 supplements, especially if you do not consume enough fatty fish.
• By making these dietary adjustments, you can increase your intake of polyunsaturated fats and enjoy their numerous health benefits.

In summary, polyunsaturated fats, including omega-3 and omega-6 fatty acids, are essential components of a healthy diet. They provide numerous health benefits, particularly for heart and brain health, and play vital roles in reducing inflammation and supporting overall well-being. By incorporating a balanced variety of these fats into your diet, you can improve your health and reduce the risk of chronic diseases.

The Importance of Moderation and Balance

While understanding the different types of fats and their effects on health is important, achieving a healthy diet ultimately comes down to balance and moderation. This approach ensures that you reap the benefits of healthy fats while minimising the potential risks associated with excessive consumption. Here are some practical tips to help you incorporate fats into your diet wisely:

• Moderate Total Fat Intake
  Although fats are essential for numerous bodily functions, they are also calorie-dense. Consuming fats in moderation helps maintain a healthy weight, preventing the negative health consequences associated with obesity. Aim for fats to make up about 20-35% of your daily calorie intake, as recommended by dietary guidelines.
  
• Focus on Quality
  Prioritise healthy fats from whole foods like nuts, seeds, avocados, and fatty fish over processed foods and fried items. Whole foods provide not only healthy fats but also essential nutrients, fibre, and antioxidants, contributing to overall health. Replace sources of saturated and trans fats with monounsaturated and polyunsaturated fats to improve heart health and reduce the risk of chronic diseases.
  
• Combine with a Balanced Diet
  Healthy fats should be part of a balanced diet that includes a variety of fruits, vegetables, whole grains, and lean proteins. This diversity ensures you get a wide range of essential nutrients necessary for optimal health. For instance, pairing healthy fats with fibre-rich vegetables and whole grains can help regulate blood sugar levels and support digestive health.
  
• Portion Control
  Even healthy fats should be consumed in appropriate portions. Nuts and seeds, for example, are nutritious but high in calories, so a small handful is usually sufficient. Being mindful of portion sizes helps prevent excessive calorie intake while still providing the benefits of healthy fats.
  
• Read Labels
  When buying packaged foods, read nutrition labels to check for trans fats and high levels of saturated fats. Many processed foods contain hidden fats that can add up quickly and negatively impact your health. Choose products with lower amounts of these unhealthy fats and higher amounts of beneficial fats.
  
• Cooking Methods
  Opt for healthier cooking methods like grilling, baking, steaming, or sautéing with small amounts of healthy oils like olive or canola oil. Avoid deep-frying or using excessive amounts of butter and lard, which can increase your intake of unhealthy fats.
  
• Incorporate Omega-3 Fatty Acids
  Ensure you’re getting enough omega-3 fatty acids by including fatty fish in your diet at least twice a week or considering omega-3 supplements if necessary. Omega-3s are particularly beneficial for reducing inflammation and supporting heart and brain health.
  
• Stay Informed
  Nutritional science is constantly evolving, so staying informed about the latest research and dietary recommendations can help you make the best choices for your health. Consulting with a registered dietitian can provide personalised advice and guidance.

In conclusion, while fats are an essential part of a healthy diet, the key lies in moderation and making informed choices. By focusing on the quality of fats you consume and incorporating them into a balanced diet, you can enjoy their health benefits without the associated risks. Understanding the importance of different types of fats and how to balance them effectively will empower you to take control of your health, leading to better overall well-being and a reduced risk of chronic diseases. Remember, the goal is not to eliminate fats but to choose them wisely and enjoy them as part of a nutritious and varied diet.

References

1. American Heart Association. (n.d.). Healthy eating: Fats. Retrieved from https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/fats
2. Astrup, A., Dyerberg, J., Elwood, P., Hermansen, K., Hu, F. B., Jakobsen, M. U., … & Willett, W. C. (2011). Saturated fats and health: a reassessment and proposal for food-based recommendations: JACC state-of-the-art review. Journal of the American College of Cardiology, 58(14), 1553-1566.
3. Dehghan, M., Mente, A., Zhang, X., Swaminathan, S., Li, W., Mohan, V., … & Anand, S. S. (2018). Associations of fats and carbohydrate intake with cardiovascular disease and mortality in 18 countries from five continents (PURE): a prospective cohort study. The Lancet, 390(10107), 2050-2062.
4. Esposito, K., Kastorini, C. M., Panagiotakos, D. B., & Giugliano, D. (2010). Mediterranean diet and metabolic syndrome: an updated systematic review. Reviews in Endocrine and Metabolic Disorders, 11, 1-16.
5. Estruch, R., Ros, E., Salas-Salvadó, J., Covas, M. I., Corella, D., Arós, F., … & Martínez-González, M. A. (2013). Primary prevention of cardiovascular disease with a Mediterranean diet. New England Journal of Medicine, 368(14), 1279-1290.
6. Harvard T.H. Chan School of Public Health. (n.d.). The Nutrition Source: Fats and cholesterol. Retrieved from https://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/fats-and-cholesterol/
7. National Heart, Lung, and Blood Institute. (n.d.). Cholesterol. Retrieved from https://www.nhlbi.nih.gov/health-topics/cholesterol
8. National Institutes of Health. (n.d.). Omega-3 fatty acids. Retrieved from https://ods.od.nih.gov/factsheets/Omega3FattyAcids-Consumer/
9. 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.
10. U.S. Department of Agriculture. (2020). Dietary guidelines for Americans 2020-2025. Retrieved from https://www.dietaryguidelines.gov/
11. U.S. Department of Health and Human Services. (2015). Dietary guidelines for Americans 2015-2020. Retrieved from https://health.gov/dietaryguidelines/2015/guidelines/
12. U.S. Food and Drug Administration. (2015). Final determination regarding partially hydrogenated oils. Retrieved from https://www.fda.gov/food/food-additives-petitions/final-determination-regarding-partially-hydrogenated-oils

• Bio

Ellyn Johnson

Ellyn is an Exercise Scientist specialising in youth Strength and Conditioning. She holds her Bachelor's degrees in Science and Exercise and Sports Science. She has previously worked as a Strength and Conditioning Coach for Academy level athletes at the Brisbane Lions Football Club. She has a background in Personal Training, coaching a range of clientele with diverse goals, including weight loss, body recomposition as well as recreational endurance athletes. In addition to her Strength and Conditioning experience, Ellyn currently works as a Learning Designer at the Australian Institute of Fitness. Here she works as a subject matter expert in the design and implementation of a range of health- and fitness-related courses and learning materials.