Fish is an excellent source of protein and omega-3 fatty acids. Americans don't get nearly enough omega-3 fatty acids or fish in their diet. We do love our fried foods, though, so when we do eat fish, chances are it has been fried. If you're going to fry your fish, canola is one of the better oils to use. The question remains as to whether the oil contributes fat or calories that detract from the value of the fish, or if the frying causes damage to the omega-3 fatty acids that contribute to the healthfulness of the dish.
Omega-3 Fatty Acids and Fat
Fat has a bad reputation, but the fact is that omega-3 fatty acids, a form of polyunsaturated fat, are essential to your health. Fats help you dissolve and use certain vitamins. You need fatty acids to regulate blood clotting and to build cell membranes, as well as for numerous other functions. Omega-3 fatty acids, in particular, reduce free radicals in your blood. Free radicals are unstable molecules that alter LDL cholesterol so it damages arterial walls, which leads to the formation of artery-clogging plaque. Omega-3 fatty acids reduce your risk of high cholesterol, high blood pressure, diabetes, coronary heart disease and stroke, as well as inflammatory bowel disease, cancer and autoimmune diseases such as rheumatoid arthritis and lupus.
Canola oil, made from rapeseed, a cousin to cabbage and Brussels sprouts, ranks as one of the healthiest oils. It is much lower than most oils in saturated fat, the kind of fat that increases bad cholesterol and contributes to coronary heart disease. Like fish it is high in polyunsaturated fat, and it is also high in monounsaturated fat. Monounsaturated fats improve cholesterol level and control blood sugar and insulin levels. Also like fish, canola oil is high in omega-3 fatty acids. Monounsaturated fats improve cholesterol level and control blood sugar and insulin levels.
Frying fish in canola oil presents two potential problems. First, though canola oil has health benefits, it is high in calories, so it is healthful only in small quantities. Second, all oils, including canola oil, have a temperature at which point the oil begins to smoke. The omega-3 fatty acids in canola oil can start to burn around 400 degrees F. When the omega-3 fatty acids break down they become oxidized into trans fatty acids, a form of fat that lowers your good cholesterol and elevates your bad cholesterol. High temperature cooking affects the flavor of the oil and reduces the nutritional benefits. Also, the smoke contains a toxic compound that might contribute to cancer risks, according to a 2001 study reported in "Journal of Food Protection."
To minimize the amount of oil that is absorbed, do not deep fry the fish. People often batter or bread their fish before frying it. Breading and batter add carbohydrates and also cause greater absorption of oil during frying. If you already struggle with weight, the extra calories diminish the health value significantly. If you sauté the fish, which means cooking at a very high temperature with a small amount of oil, you reduce the amount of oil, and also oxidize some of the omega-3 fatty acids. If you pan fry the fish in a small amount of oil, cooking at a somewhat lower temperature, you spare more of the omega-3 fatty acids. Frank Sacks from the Harvard School of Public Health says that even after frying, fish still has intact omega-3 fatty acids. So, though carefully fried fish is still healthy, you obtain the greatest benefits by baking it.