But you also have people who specialise purely in the physical illnesses, known as a herbalist, inyanga in Zulu.

BBC: Witnessing a South African healer at work

These men are also struggling with mental and physical illnesses, addictions and other issues related to combat, service and life.

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Many people with severe mental health problems miss out on the care they should receive for physical illnesses, researchers say.

BBC: Mental health medication concern

The physical illnesses, and medications used for them, also can complicate treatment.

MSN: Boomers will be in need of mental health care, report finds

Liberal Democrat Lord Alderdice, who co-sponsored the amendment, said the issue was about making "absolutely clear" that concern for those with mental health issues "is every bit as great" as for people suffering from physical illnesses.

BBC: Government suffers defeat over NHS Bill

The phrase nature deficit disorder was coined in 2005 by author Richard Louv, who argued that the human cost of "alienation from nature" was measured in "diminished use of the senses, attention difficulties and higher rates of physical and emotional illnesses".

BBC: Nature deficit disorder 'damaging Britain's children'

Studies indicate as many as 40% of patients with serious illnesses like cancer struggle with spiritual concerns, which can harm emotional and physical well-being, says George Fitchett, research director in the Department of Religion, Health and Human Values at Rush University Medical Center Chicago.

WSJ: Hospital Chaplains Seek Bigger Roles on Patient Medical Teams