Is writing poetry theraputic?

Here is a website which says so:

http://www.poeticmedicine.com/

Some people say it is but poets have a much higher suicide rate than any other  people/

I read:It is diagnostic but not therapeutic [Sylvia Plath]

I also read that writing to a strict form is more likely to help you then writing free verse...seems intriguing.I believe if you have suffered a lot in life,writing may bring it to the surface.Fiona Sampson in  The Expert Guide to Poetry Writing advises one to keep the phone number of the Samaritans to hand!That tells you a lot.I wonder what T.S.Eliot would say or Ted Hughes?What do you think?