Over-the-counter vitamins and supplements are good ways to obtain additional nutrients needed for health but not all brands are the same.
Since the vitamin and supplement industries are not regulated by the FDA, consumers need to do their homework. Many of the brands available in your local grocery stores or pharmacies do not provide the highest quality ingredients, some of their supplements (i.e. fish oil may also be rancid !) or packed with fillers, which for people with autoimmune illnesses can be a problem.
It is best to get these vitamins, nutrients through foods. However, due to many factors supplementation is often needed. Utilizing a manufacturer that tests its products and avoids fillers, soy, gluten, artificial colors and genetically modified organisms (GMOs) are important.