Are dietary supplements bad for you? They can be, but it depends on many factors. What is your overall health? Do you eat a poor diet or a good diet? Do you take any medications? How many supplements are you taking, and which ones? Supplements include vitamins, minerals, herbs, and many other preparations. While most people are aware that they can take too much of a particular supplement and overdose on a vitamin, for example, few are aware that supplements may be masking their problems or adding to a body already struggling to remove toxins.