Perhaps the next prescription from your doctor will be for something a little different: contact with nature.

Many studies have looked at the positive impact of nature on emotional and physical health. Some research has suggested that we are genetically hard-wired to seek green surroundings for our health and well-being.

What are some health benefits of contact with nature and greenery?

Here are surprising findings from studies over the past few years:

* Green environments improve mental acuity. Children who play in playgrounds seem to have higher scores for attention than those who play on asphalt. In a study of 96 children diagnosed with attention-deficit hyperactivity disorder, the greener the play area, the better the concentration and mental functioning.

* Green environments reduce aggression and crime. A 2001 study showed that housing blocks in Chicago with high levels of greenery had about 50 percent fewer property and violent crimes, compared with housing areas with little vegetation.

* Green environments reduce stress, depression and anxiety. A 2005 study in Sweden found that the more often one visits green areas, the less often one reports stress-related sickness. Other studies have shown that doing exercise in nature reduces depression and anxiety in adults.

* Green environments improve the functioning of the body's immune system. A 2007 study in Japan showed that a three-day exposure to nature increased the body's natural "killer cells" by 50 percent. A 2008 study showed that enhanced activity of white blood cells lasted more than a week after exposure to nature.

* Green environments lower blood pressure. In a study this year of 280 people in Japan, scientists found that walking through a forest or other wooded area for a few hours lowered concentrations of the stress hormone cortisol, lowered the pulse rate and lowered blood pressure.

* Green environments make one feel healthy. A 2006 epidemiological study in the Netherlands on more than 250,000 people showed that the percentage of green space in a living environment has a positive association with residents' perceived general health. This was most apparent among the elderly, housewives and lower socioeconomic groups.

In fact, the Japanese have a name for exposure to greenery, "Shinrin-yoku" -- roughly translating as taking in the forest atmosphere or forest bathing. We think this is a great prescription for overall good health and should be taken often.

So go ahead and take one Shinrin-yoku and call us in the morning.