However, these depressing figures show that these difficulties really exist. The prevalence of mental illness, which affects 46.6 million Americans or one in five people, has been rising recently, particularly among young adults. Significant disparities also exist: Communities of color are frequently provided with lower-quality mental health care, have less access to mental health services, and are less likely to receive a diagnosis and treatment for their mental illness, according to the U.S. Department of Health and Human Services.