What are the positive effects of gambling?

There are none. 

Total waste of time, money. Save and invest the money. 

There are no positive effects of gambling.

There aren't any.

There aren't any, except for the bookmakers.  They get filthy rich.

Well if you are good at it, professional gamblers make good incomes even at an expected success rate of about 55%.  Too much of anything can make people addicts, so as far as addictions go, there are certainly worse ones than gambling.  Also, I agree with Jonathan's response for happiness, and social well being.

Health benefits of gambling

Makes you Happier. Studies by the Behavior analysis and therapy program at Southern Illinois University have shown that gambling can positively improve your mood and cause happiness

Improves your Skills. Gambling enables you to pick up skills while playing

Helps with Socialization

http://www.mynetsohbetci.net/bedava-spin-veren-bah...