When it comes to mental health, what goes on in your gut matters. And, according to Dr. Uma Naidoo, that includes consuming things like chocolate! "Fiber is extremely important for your gut health and you can get it from vegetables, berries, fruit, colorful salad — but you can also get it from extra-dark natural chocolate, (which is) rich in things like serotonin," Naidoo said in an interview with CBS News. Naidoo added that foods like chocolate can be useful in battling depression, saying, "A population-based study of more than 13,000 individuals showed an improvement of more than 70% in depression. So your gut health is also your mental health — it's your physical health, but it improves things like your mental well-being as well."Naidoo did specify that natural dark chocolate would be the most beneficial and warned people to stay away from candy bars.