OTC and vitamin e will not have any side effects unless they are taken in ultra-high doses for a long time. Just take it according to the instructions. The human body's tolerance to vitamin E is not generally high. In addition, OTC is cheaper than those health care products, and the production process of vitamin E is not a difficult technology. Health care products are so expensive that almost all of them pay IQ tax ... the extra money is used to buy brands and additives.