About 50% of adults believe cannabis relieves symptoms from anxiety, stress, and depression, a 2018 national survey reported. One rat study reported cannabis could relieve stress-induced depression and Canadian researchers found marijuana was an effective anti-depressant at low doses. But using marijuana dramatically spiked, particularly for those with depression. A new study found people with depression were double the risk of using marijuana than those without, and were more likely to consume at a near-daily rate. In 2005, those with depression were 46% more likely to consume marijuana, but by 2015 they were 130% more likely to do so.