About 60% of U.S. Armed Forces personnel regularly used dietary supplements.   A study found those using multivitamin/protein supplements were more awake, relaxed, cheerful, clearheaded, and coordinated.  These people were also more likely to report their general health, eating habits, and fitness level as excellent or good.  In contrast, those who used protein supplements and purported steroid analogs were less friendly or more aggressive.Multivitamin is known to provide many health benefits and protein supplements help grow muscle mass and increase physical strength.  (David Liu PHD)Austin KG, McGraw SM, Lieberman HR.  Multivitamin and Protein Supplement Use Is Associated With Positive Mood States and Health Behaviors in US Military and Coast Guard Personnel.   J Clin Psychopharmacol. 2014 Aug 13.