Niacin
"I recently watched the movie Food Matters and learned that Niacin can be used to treat depression and alcoholism in addition to high cholesterol. I began taking last week, and have noticed a gradual improvement in my mood as I increase the dosage. Make sure you start low and increase gradually, though: the first time I took it I took 100mg with a light snack and ended up stripping down and standing in my kitchen panting, but there were no lasting negative effects."