After the low-fat diet craze of the 1990s, fad diets moved on to other targets like carbohydrates. But ever-changing diet marketing might have you confused: Is fat the nutritional villain? Or is it okay, or even good, to consume it every now and then?
As a registered dietitian and licensed nutritionist, I hear these questions all the time from my patients. Let’s get the facts straight.
Is dietary fat good or bad?
Nutrients cannot be simply categorized as good or bad. It’s the amount and type of fat in your diet that matters.
Eating too much of any macronutrient (the main ones being carbohydrates, protein and fat) can be potentially harmful. When you eat more calories from fat, carbohydrates and protein than you burn, the excess calories are stored as body fat.
Having some fat stored in the body is good because it protects your organs and keeps you warm. Your body also needs fat to absorb fat-soluble vitamins, like vitamin D. Fat also plays a role in hormone production and cell function. But having too much fat stores is a risk factor for diseases like diabetes, heart disease and some cancers.
As science evolves, medical professionals continue to adjust their recommendations to align with the latest evidence. Many years ago, medical professionals recommended a low-fat diet to prevent chronic diseases such as heart disease. Recent evidence suggests that it is important to focus on the types of fats you consume, rather than the total amount of fat you consume.
What are the types of fat?
There are many different types of fats, which are classified based on their chemical composition.
Trans fats They are formed when hydrogen is added to unsaturated fats. Hydrogenated fats are found in packaged foods like cookies and cakes. To find out if a food contains trans fats, look for partially hydrogenated oils on the ingredients list.
Trans fats can have a negative impact on cardiovascular disease and are so bad for your health that the U.S. Food and Drug Administration has banned food manufacturers from adding artificial trans fats to foods and beverages.
Some meat and dairy products contain small amounts of naturally occurring trans fats. It is not clear what effect these fats have on your health.
Saturated fats Saturated fats are found in meat, dairy products, butter, and coconut oil. Saturated fats are generally associated with an increased risk of cardiovascular disease. However, it is important to consider the type and source of saturated fat. For example, dairy products contain saturated fat, but they also contain important nutrients such as calcium and protein. It is important to consider the overall composition of your diet rather than focusing on individual nutrients or foods. The American Heart Association recommends limiting saturated fat intake to 5% to 6% of daily calories.
More and more research is coming out that shows just how complex this topic is. You can find out more about this topic on fat and dairy here.
Unsaturated fats It can be divided as follows:
- Monounsaturated fatty acids. Experts speculate that these fats contribute to better cardiovascular outcomes, at least compared to saturated fats. However, monounsaturated fats can be found in foods that are also rich in saturated fats, such as red meat and dairy products. This is one reason why there is no clear consensus on how much monounsaturated fat you should have in your diet. However, many vegetable oils and plant foods, such as avocados, pumpkin seeds, almonds, cashews, and peanuts, are high in monounsaturated fats and low in saturated fats.
- Polyunsaturated fatty acids. Nearly all fatty acids can be produced by the body. However, some polyunsaturated fats cannot be produced by the human body and must be obtained from the diet. These fats are known as omega-3 and omega-6 fatty acids. These fatty acids are found in fatty fish such as salmon, cod and lake trout, shellfish, soybeans, walnuts and canola oil. Dietary polyunsaturated fatty acids have been associated with a lower risk of cardiovascular disease and may also be linked to a lower risk of Alzheimer’s disease and improved biomarkers for type 2 diabetes.
What foods should you focus on to improve your heart health?
To improve heart health:
- Focus on a diet rich in foods high in unsaturated fats, such as fish and walnuts.
- Limit your intake of foods high in saturated fats, such as meat and butter.
- Read ingredient lists and avoid foods that contain trans fats.
Organizations such as the United States Department of Agriculture (USDA) and the American Heart Association recommend a diet high in lean and plant-based proteins, whole grains, fruits, vegetables, and low-fat or non-fat dairy products for overall health and wellness.
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