The start of a new year is the perfect time to set professional plans and physical fitness goals, and it's also a great opportunity to make a commitment to better your mental health. But often, that's much easier said than done.

Mehmet Oz — famously known as Dr. Oz — has dished out health and wellness advice for nearly a decade on his talk show, "The Dr. Oz Show." And, in his expert opinion, the most beneficial thing you can do for your mental health in 2019 is simple and straightforward. The best part? It won't cost you a cent.