Anthocyanin contained in blueberry is also an antioxidant. If you want to talk about side effects, you can't take it too much, and it can't exceed 12mg per day. Generally, each product is marked with a dose. An aunt has a serious cataract, and she relies on lutein to improve and relieve it, but she eats the brand of Xinyang in Taiwan Province Province. I wonder if other brands have the same effect.