You should try harder to improve your diet. Your current reading shows that you are not yet eating enough fruits and vegetables. If you find it difficult to increase your value solely through the consumption of fruits and vegetables, you can also take a good dietary supplement. In any case, avoid stressful loads and protect your body. Healthy sleep will also help you improve your readings. If you smoke, reduce your consumption or, better still, stop smoking completely. If you progress along this path and are healthy, your antioxidant levels will visibly increase in time. But don't expect sudden changes, give your body some time.