Lignans are a type of phytonutrient that have a high content of vitamins, mineral enzymes, fiber and antioxidants. They are found in the outer seed coat or covering of seeds and grains such as flax, barley, rye and millet where flax is by far the richest source that has been identified. The powder that you receive and intake is actually the waxy coating of the flax hull that has been knocked off through a gentle tumbling process.