Never heard of flaxseed? Flaxseed is the seed of the flax plant, and it's high in fiber, omega-3 fatty acids and phytochemicals. It can help reduce total blood cholesterol and low-density lipoprotein (LDL) cholesterol, which may reduce your heart disease risk. Buy whole, raw flaxseed at your local grocery or health food store and grind it in a coffee grinder, or buy pre-ground flaxseed. Add a spoonful of flaxseed to your cereal, oatmeal or yogurt, or mix into cookies, muffins and other baked goods.