Each of these Quest Support Vitamin E capsules provides 400iu of Vitamin E. Vitamin E is required to fight off oxidative stress and damage. It protects the brain, nerves, muscles, heart, arteries, glands, reproductive system, and digestive system from such activity. Vitamin E may also protect the lungs against air pullution and environmental damage. It may also provide cellular protection from damage by toxic chemicals found in food and water. Vitamin E can also help to slow down the ageing process and prevent premature ageing. Vitamin E is naturally found in foods such as vegetable oils, nuts, whole grains, wheat germ, liver, avocados and asparagus. However the modern day diet often means that we are left deficient in this key nutrient.