Final answer:
St. John's Wort is an herbal supplement that is commonly used to treat depression and improve mental health.
Step-by-step explanation:
St. John's Wort is an herbal supplement that is commonly used to treat depression. It is thought to improve mental health by increasing the levels of certain neurotransmitters, such as serotonin, in the brain. Depression is a common mental disorder that affects many people, and St. John's Wort can be a helpful treatment option for some individuals.