Flaxseed oil, also known as linseed oil, is a natural oil derived from the seeds of the flax plant. It is rich in alpha-linolenic acid (ALA), an omega-3 fatty acid that is beneficial for heart health. Flaxseed oil is commonly used in cooking and as a nutritional supplement due to its high levels of healthy fats and antioxidants. It has a delicate nutty flavor and is also used in cosmetics, paints, and varnishes due to its drying properties when exposed to air.