Trans fats are widely considered unhealthy dietary fats that should be limited or avoided. These fats are often found in processed foods, such as baked goods, margarine, and fried items, and can increase levels of LDL cholesterol while decreasing levels of HDL cholesterol, leading to higher risks of heart disease. It is recommended to choose healthier fats, such as monounsaturated and polyunsaturated fats, and incorporate sources like nuts, seeds, and fish into the diet to support overall heart health.