Mental Health and Mood Skin, Hair, and Nails: Biotin, collagen, and antioxidants like vitamin E can enhance the health and appearance of your skin, hair, and nails. Mental Health and Mood: Omega-3 fatty acids, vitamin D, and some herbal supplements like St. John's Wort may have a positive impact on mood and mental health. Digestive Health: Probiotics can help maintain a healthy gut microbiome and aid digestion,...