Yes. Most multivitamins are designed to be taken every day. There haven’t been many studies that look at long-term multivitamin use (every day for several years), but preliminary research suggests that there aren’t many side effects from long-term use. Our bodies don’t develop a tolerance to vitamins, so they don’t stop making them naturally (especially when it comes to essential vitamins, which they don’t make at all). As long as your doctor agrees, there aren’t any problems with taking a multivitamin every day. In fact, taking them for several years may help to ease the aging process, helping you feel younger as your vitamin levels stay strong.