Supports mood regulation and emotional wellbeing. Promotes a feeling of calmness. Full Spectrum® Whole Herb Formula. Science-Backed Quality Since 1969. Vegan, Gluten Free, Non-GMO. Swanson St. John's Wort leads the way in supplements for mental and emotional health. The leaves and flowers from this shrub are used to support mood and emotional health while helping your body when you're feeling stressed and nervous. St. John's Wort has become one of the world's most popular herbal supplements, thanks to the unique support it provides for emotional wellbeing.