Fats are the most energy dense of the three macronutrients. They provide about 9 calories per gram, while carbohydrates and proteins provide about 4 calories per gram. There are a variety of different types of fat. Fats are broken down into animal-based fats (saturated fats) and non-animal fats (unsaturated fats).
Specific examples for the types of fat are listed below with a brief description of whether a particular fat is healthy or unhealthy.
Types of Fat: A Complete Visual Breakdown
Saturated fats contain single bonds between carbon atoms; therefore, all the remaining bonds attach to hydrogen and are fully “saturated”. They are present primarily in animal products such as beef, pork, chicken, shellfish, egg yolks, and dairy such as cream, milk, and butter. They are also present in coconut oil, palm oil, lard, and vegetable shortenings. In general, saturated fats are unhealthy while unsaturated fats are healthy with the notable exception on trans fat, which is highly unhealthy.
Unsaturated fats are fats that contain a at least one double bond in between carbon atoms. They are broken down into monounsaturated fats and polyunsaturated fats. Monounsaturated fats are extremely healthy. Examples of foods high in monounsaturated fats include almonds, nuts, avocados, olive oil and canola oil. Polyunsaturated fats both healthy fats and fats that are generally healthy but unhealthy when consumed in excess.
There are two mains types of polyunsaturated fats: omega-3s and omega-6s. Omega-3s are considered very healthy. Examples of foods high in omega-3s include fish, nuts, pumpkin seeds and flaxseeds. Omega-6s are also generally considered healthy but can be unhealthy when consumed in excess. Examples of foods high in omega-6s include corn, soybean, safflower, sunflower, and cottonseed oil. Trans fat is a special type of polyunsaturated fat that is man-made and formed by “transforming” polyunsaturated liquid fats (corn, soybean, safflower, sunflower, and cottonseed oils) to solid fats. (See Polyunsaturated Fat).
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