A shared universe › Blog › What a while among trees does · Español
Spending time in nature is linked to less stress and feeling better: in a large survey, people who spent at least two hours a week in natural spaces reported better health and greater well-being. Almost everyone notices that a walk in the countryside does them good. The hard part was measuring it, and one of the first studies was carried out in a hospital.
In 1984, the researcher Roger Ulrich went through the records of patients who had had gallbladder surgery between 1972 and 1981 at a hospital in Pennsylvania, in the United States. He compared 23 who had been in rooms whose window looked out on some trees with another 23, similar in age and circumstances, whose window faced a brick wall.
According to his study, published in the journal Science, those who could see trees went home sooner, took fewer strong painkillers and had fewer unfavourable comments in the nursing notes. It was a small study based on records, not an experiment, but it opened up a field of research that is still growing.
The psychologist Stephen Kaplan was one of the figures who proposed an explanation, known as attention restoration theory, which he brought together in a 1995 paper on the restorative benefits of nature. In the city and in front of screens, attention has to make a constant effort not to be distracted. In nature, attention drifts without effort: leaves, water and clouds draw the eye without demanding anything. That time allows tired attention to recover.
The idea has been tested many times, with more modest results than are usually reported. In 2016, a review of 31 studies found improvements in three of the attention tests analysed, but not in the rest, and concluded that it is still unclear which aspects of attention improve.
In 2019, the researcher White and colleagues analysed a survey of nearly twenty thousand people. Those who had spent at least 120 minutes in nature in the previous week more often reported good health and high well-being than those who had not been at all. The benefit stopped growing at around three to five hours a week, and it made no difference whether the two hours came in one long outing or several short ones.
Another 2019 study, with 36 people who lived in a city, measured a stress-related hormone before and after spells in green spaces. The greatest benefit per minute came between 20 and 30 minutes, although there was still a little more after that.
The authors themselves urge caution: these are associations and small studies, and more research is needed before nature can be prescribed in minutes. But they point in the same direction.
What is known suggests looking for whatever nature you have to hand, often and without big plans:
If you have limited mobility or live far from a park, small things count too: a square with trees, a balcony with pots, opening the window and spending a while looking out. Small things, repeated often, also add up towards those two hours a week.
As you walk, notice one detail: the smell after rain, the sound of the leaves, the light between the branches. Pausing on what is good makes it last longer, as we explain in savouring the good moments.
The sky is the nature we all have, wherever we live. Why looking at it does us good is in awe.
A shared universe was born from that idea: looking at a night sky and knowing that others are looking at it at the same time. There you can light a star with “What I’m grateful for” for that walk, that tree or that time outdoors that gave you back your calm. It will shine for seven days, and other people can keep it company.