When it comes to diet control or weight loss programme, the first solution that comes to our mind is to completely remove or banish fat from our diet. It is true that certain types of fat and its products e.g. saturated fat (SFA), cholesterol and trans-fat are harmful as their high intake may play a role in cardiovascular disease, diabetes, cancer and obesity. However, it is to be noted that not all fats are created equally. Some fats are infact essential (MUFA and PUFA) meaning they're required for normal body functions and can't be synthesized by our body and therefore should be present in our diet. Also fat is present in every cell in our body, and is required for their proper functioning. It's a major source of energy (9 kcal per gram) and provides satiety.
Certain bodily functions also rely on the presence of fat e.g. some vitamins (Vitamin A, D, E and K) require fat in order to dissolve into bloodstream and provide nutrients. Thus, fats are important and we cannot survive without them. Indian Recommended Dietary Allowances (RDA) recommends a minimum intake of total fat of 15-30% and SFA of <10% in diet. The U.S. Department of Agriculture's Dietary Guidelines recommend that adults get 20-35% of their calories from fats and limit saturated fats to 10% or less of total calories and trans-fat to less than 2 grams per day, while the American Heart Association (AHA) recommends keeping saturated fats to just 7% of total calories and trans-fats consumption as low as possible.
Under healthier or good fat categories come monounsaturated and polyunsaturated fats and omega fats.
Monounsaturated Fat (MUFA)
MUFA are fatty acids that have one double bond in the fatty acid chain with all of the remainder carbon atoms being single-bonded. These can improve blood cholesterol level and decrease risk of cardiovascular disease. Some foods rich in monounsaturated fats are nuts (almonds, cashews, hazelnuts, peanuts, pecans, etc.), vegetable oils (olive oil, canola oil, peanut oil, etc.), avocado, sesame seeds, pumpkin seeds etc. Monounsaturated fats are typically liquid at room temperature but solidify if refrigerated. These heart-healthy fats are typically a good source of the antioxidant vitamin E.
Polyunsaturated Fat (PUFA)
PUFA are fatty acids that have more than one double bond in the fatty acid chain. They are of two main types: omega-3 fatty acids and omega-6 fatty acids. The numbers refer to the distance between the beginning of the carbon chain and the first double bond. Plant-based foods and oils are the primary source of this fat. Like MUFA, polyunsaturated fat can decrease risk of heart disease by lowering blood cholesterol levels. Especially, omega-3 fatty acids (ALA, DHA, and EPA), have been shown to be particularly beneficial. Omega-3 fatty acids not only appear to decrease the risk of coronary artery disease, but also may help lower blood pressure levels and guard against irregular heartbeats. They are also important for ensuring good brain function and structural integrity. They are found in fatty fish (salmon, herring, sardines, trout, catfish, mackerel), as well as flaxseed, chia seeds, walnuts and canola oil, although plant foods contain a less active form of this fat than fish. Indian RDA recommends intake of PUFA to be 8-10% of energy intake from fat and remaining fat calories from MUFA. A minimum intake of omega-3 of 200 mg/day in diet is also recommended.
Overall, we can conclude that healthier fats should be an important part of our diet and like everything should be taken in moderation to yield their full benefits.