I would say that the methods leading to enlightenment will help with stress, but only indirectly. Once you've begun to do away with the delusions that cause you suffering, life starts to go a lot more smoothly. But the practice that most directly aims at that is not a relaxing one and is not one that I would ever recommend to someone to control their stress levels for immediate relief.

Parenthetically, some people find that, with partial enlightenment, the practices that directly improve mood and stress levels become ridiculously easy (for those who care to indulge). Most beginners typically find the same practices hard to execute successfully.