Mental health benefits | More about mental health benefits of forests
Text is extract from the Report for the Health Council of the Netherlands and Dutch Advisory Council for Research on Spatial Planning, Nature and the Environment. 2004. Nature and Health. The influence of nature on social, psychological and physical well-being. 
The whole report (pdf)
Recovery from stress and attention fatigue. A first way to look into an indirect influence on health is to establish whether exposure to nature is instrumental in recovering from stress and attention fatigue. If so, this is of great importance. Chronic stress plays an important role in the aetiology and course of severe, common physical and mental illnesses and health problems. Stress-related mental problems such as anxiety disorders and depression are common. They are major causes of absenteeism and work disability. A large number of studies, all using sound methodology, have produced strong evidence of the positive effect of nature on recovery from stress and attention fatigue. Exposure to nature has proved to have a positive effect on mood, for example, as well as on concentration, self-discipline and physiological stress. The studies were conducted both in the laboratory and under field conditions. The beneficial effects occur even after brief exposure to a view of nature.
Facilitating social contact. Can nature facilitate social contact? If so, this would also establish a positive link between nature and health. People with many social contacts feel healthier, have a lower risk of cardiovascular disease and live longer. Among older people, more social contacts are linked to a longer life and reductions in the prevalence of depression and cognitive impairment. Social contact not only prevents loneliness, it also results in more social support and concrete assistance in difficult situations and encourages healthy behaviour. Individualisation in society is making social contact more difficult.
Encouraging optimal development in children. The healthy development of children contains many keys to the physical, psychological and social well-being of adults. To what extent does exposure to nature contribute to a healthy development in children, resulting in better health later in life? Opportunities to play and learn are important for the cognitive, socio-emotional and motor development of children. The elimination of natural environments from the immediate living environment and a reduction in the freedom of movement are depleting the opportunities for contact with nature. It is possible that children cannot recover from stress as quickly when there are not enough green spaces in their surroundings, and stressful experiences early in life can have a long-term effect on their behaviour and health.
Providing opportunities for personal development and a sense of purpose. Studies of leisure time spent in natural surroundings have indicated that nature creates the conditions for a sense of purpose; stimulating feelings of relaxation, autonomy and competence makes people more open to reflection. In addition, because of its symbolic significance, nature can contribute to a sense of purpose. Natural elements and locations can refer symbolically to convictions and values that give meaning to life.