Dietary supplements have been known to cause unsuspecting consumers to end up in a hospital with a variety of severe health problems. These supplements deceive people into buying them due to their supposed benefits, but they have toxic substances hidden within the ingredients. Studies by Pieter Cohen, a Harvard graduate, have revealed a variety of flaws within supplements including liver toxicity, etc., but companies continue to incorporate untested ingredients such as yohimbe, acacia, and St. John's wort into their supplements that have not been tested for safety or FDA approved. Many people are still taking acacia in various forms in order to heal wounds, help indigestion, cure colds and coughs, and just as a source of fiber. Others take yohimbe in order to increase athletic performance, aid weight loss, exhaustion, chest pain, help blood pressure and diabetic nerve pain, and minimize depression. The majority of people are swayed by the promising effects of St. John's wort to help minimize the conditions of depression including anxiety, tiredness, loss of appetite and trouble sleeping. By studying the toxicity and effects of certain supplements on Dugesia dorotocephala, I hope to model the effects that these supplements may have on humans. Planarian were chosen since they are invertebrates that share a similar nervous system to that of humans and other vertebrates. The purpose of this experiment is to determine the effects of three different concentrations of yohimbe, acacia, and St. John's wort extracts on the mobility rate and catalase activity of Dugesia dorotocephala. The planarians were fed three days prior to the experiment, and after 72 hours, groups of ten were exposed to 30 mL of a supplement solution. There were 10 groups total including a control group, three different concentrations of acacia (25, 30, 35), three different concentrations of yohimbe (15, 20, 25), and three different concentrations of St. John's wort (5, 7.5, 10). The solutions for each petri dish was changed every 24 hours, and their mobility rate was also taken by placing each dish on a 0.6 cm square grid and videoing each dish for 5 minutes. The video was then used to count the total number of gridlines crossed by the planarians within the time frame for each dish. This mobility assay was repeated every 24 hours for 96 hours. Once this regeneration assay is finished, a catalase assay was performed on all 10 dishes to compare differences in catalase activity. The results from an ANOVA test showed a highly significant decrease in the mobility rate of planarian in the experimental groups compared to the control all having a p-value less than 0.01. Another ANOVA was performed on the data collected from the catalase assay, which proved to be insignificant due to the supplements due to the high variation between individual planarians and the lack of a sufficient number of planarian to perform accurate tests.