Research has shown that meditation can help improve sleep.

In a study on older adults with sleep disturbances, a meditation program for 6 weeks saw significant improvements in their ability to fall and stay asleep.

Patients from another study with chronic primary insomnia indicated improvements in sleep latency, total sleep time, total wake time, wake after sleep onset, sleep efficiency, sleep quality and depression.

In general, hyperarousal is a causative factor in insomnia. Meditation triggers the relaxation response in the body, which is the polar opposite of the fight/flight response.

For the scientists among us, links to specific research papers can be found here, here, here, and here.