I started taking the spice turmeric a month ago at 4.5 grams per day (actually it's two 720 mg capsules three times per day or 4.32 gm) and turmeric is known for improving mood which it does for me. I can vouch for turmeric and although I wasn't depressed, I can't imagine turmeric not helping a depressed person.
I also had some muscle pain which improves with taking turmeric.
Turmeric increases new brain cell formation by 80%, so it is thought that turmeric protects against and helps recovery from dementia and Alzheimer's.
I plan to take turmeric powder soon and probably will take 1.5 level teaspoons three times per day. A half level teaspoon is 500 mg turmeric, is what I read, so I will be taking probably around 4.5 grams per day of the powder and may even increase it if I can. It did cause loose bowels at first, but that seems a good way to determine dose is to stay below bowel tolerance.
People are advised not to take blood thinners or anticoagulants while taking turmeric.