Most of us would agree that it always feels good being out in nature. But what does the research say? Is it really healthier? This article discusses what researchers in The Netherlands have found out about the health benefits of “going green”.
A short walk or just hours wandering through nature, growing vegetables together in a community vegetable garden or working in an office full of plants: green feels good. And: green is good. Contact with nature increases happiness and reduces stress.
It promotes vitality, creativity and stimulates encounters between people. Researchers from Wageningen University & Research are therefore working on various Green for Health projects.
For example, ‘We discovered that the greener the living environment in poor neighborhoods, the fewer children aged five to twelve use ADHD medication’.
When in the 1980s the effect between green space and health was investigated, the results were so remarkable that the top science magazine (1984) made room for them. The American Roger Ulrich showed that patients who had a view of green trees after gallbladder surgery recovered faster than those who looked out on a stone wall.
This study was the starting shot for many studies into the healing powers of nature. Dutch research also shows that people who live in green areas feel healthier more often and are sick less often. Green reduces stress, for example because seeing nature alone has a calming effect.
Green encourages encounters between people and provides more varied play for children
says researcher Sjerp de Vries. For example, children in green neighbourhoods are fifteen percent less likely to be overweight.
The greener the living environment, the fewer children aged five to twelve use ADHD medication. Together with two research institutes in the field of health, the NIVEL and the Julius Centre (UMC), Wageningen University & Research studied the relationship between how green the living environment is and the use of ADHD medication such as Ritalin. Data from the Achmea Health Database on almost 250,000 children were used. The living environment is defined as a circle with a radius of 250 meters around the house.
The greener the living environment, the lower the incidence of ADHD medication use within this age group. The relationship turned out to be strongest in the poorest neighbourhoods and absent in the richest neighbourhoods (based on the REV (Real Estate Value) value of the homes).
The results are therefore consistent with those of other research in which the relationship between the presence of green space and health was also found to be stronger with a lower socio-economic status.
But not everyone has easy access to a garden, park or street green. Researcher Jan Hassink: ‘For vulnerable groups, such as the elderly and people with a low socio-economic status, the use of greenery is important. It improves their health and well-being. Access to green space can contribute to reducing socio-economic health differences.
These are differences in health and mortality between people with a high and people with a lower (socio-economic) position in society. But the latter group often has less access to green space. And the quality and maintenance level of green space in their living environment is often lower, so the effect of green space is probably also lower’.
In Arnhem and Nijmegen the researchers are therefore looking at how, together with residents, they can make vulnerable neighbourhoods greener in such a way that all residents come into contact with greenery and actively use it.
Researcher Lenneke Vaandrager is project leader of the PARTIGAN consortium: ‘We are investigating how residents use and value parks. We are following redevelopment projects in which streets are made greener. And we want to know how residents experience green civic initiatives: we measure the effect on health and well-being.
Think, for example, of a neighbourhood vegetable garden, set up by the residents themselves, where they roll up their sleeves together and prepare meals using vegetables and herbs from their own garden.
What do we expect? That when people work in the vegetable garden, they get more social contacts, experience less stress and feel healthier. They will also live healthier lives because they are more active and eat healthier food’.
It is not only in Arnhem and Nijmegen that residents may be more actively involved with nature and eat healthier food. Children in Amsterdam see apples and pears growing in the orchard on a daily basis and are allowed to help maintain the trees and harvest the fruit themselves.
Here, Wageningen University & Research is involved in Fruit4Schools, an initiative that brings social institutions, parents and children into contact with healthy food in a playful and above all natural way. Primary and secondary schools, local businesses, municipalities and other interested parties work together so that fruit can be produced on schoolyards.
Project leader Marc Ravesloot: ‘This is linked to environmental education: the children eat the cultivated fruit in the classrooms, if necessary supplemented by the local greengrocer. In this way, children and their parents become more aware of how our daily food is produced and what the influence of healthy food is on a healthy lifestyle’.
A healthy lifestyle also includes plenty of exercise. Several schools are therefore undergoing a metamorphosis into “Healthy Schoolyard”. A square where you can hide in the bushes, where you can climb over tree trunks or stomp into puddles with your boots. In short: where children have the space to play in a challenging and green environment.
Together with TNO, Wageningen University & Research has conducted research into the effect of this redesign at four primary schools. The researchers looked at the degree of physical activity, cognitive functioning, the social climate on the square and in the classroom and, more generally, the socio-emotional well-being of the children.
The outcome: according to the children there is less bullying on the square and fewer children are on the side during the break. This is probably mainly due to the greater variety that the new squares offer.
Several schools exchange the grey tiles for plants and trees. This also happens in health care. Jan Hassink: ‘For example, clients work at care farms, 1200 of which are already in the Netherlands. They feed the animals or work in the vegetable garden. The farmers and farmers’ wives provide the care. The peace and quiet and the space of the countryside contribute to the well-being of these people: they experience less stress, fear or pain.
These activities are popular with different groups of clients such as people with mental disabilities or psychological problems, vulnerable elderly and young people with behavioural and emotional problems. In this way they can take part in society in a meaningful way’.
The researchers want to know how participants and their informal carers experience this form of care. Where participants used to be cared for in care institutions, nowadays care mainly takes place at home. This is only possible if informal carers are relieved, for example by the availability of appropriate day care. Together with stakeholders, we look at the effective principles and points for attention and improvement, which we jointly translate into a quality framework for care agriculture,’ says Hassink.
A meaningful daytime activity is also important for people living at home with dementia and their carers. According to Vaandrager, it is still a problem to find something suitable. When looking for day care, you quickly end up with games and coffee.
Many people with dementia actually benefit from something else. They become happier when they are active, spend a large part of the day outside and choose for themselves what to do. We see that in the city recently several green initiatives are popping up: from gardening to caring for animals.
Because this is a relatively new way of spending the day, little is known about the diversity and value of these green initiatives. The aim of our research is to investigate the characteristics of green initiatives in urban areas and to find out what the significance of these green initiatives is for people with dementia and their carers’.
Green also makes us feel comfortable on a hot summer day in the city. A good and dispersed amount of city green combats city heat. PhD student Wiebke Klemm studied the contribution of city green to so-called thermal comfort: how (un)pleasant the interplay of temperature, wind, humidity and radiation feels. Her conclusion is clear: ‘Urban green ensures that we feel ‘thermally’ pleasant.
In our experience, water or the shade of buildings does not match the cooling effect of trees. The measurement data we have gathered from cycling around with two cargo bikes full of measuring equipment also show that green spaces are the cooling islands in a city.
Ten percent more tree cover, for example, results in a radiation temperature that is more than three degrees lower. Climate change will increase the heat in cities and thermal comfort will become increasingly important in the design of outdoor spaces’.
The air we breathe outdoors on such a sunny day is often of better quality than the air indoors. It is often downright bad. This is due to poor ventilation, high CO2 concentrations and volatile substances emitted by, for example, floor coverings, wall panels or electronic equipment. Sick building syndrome was first mentioned in the 1980s.
Unhealthy indoor air causes health complaints such as headaches, irritation of mucous membranes or allergies. Project leader Tia Hermans: ‘Healthy air is important for a good learning climate for children and a good working climate for employees. The more CO2 there is in the air, the harder it is to concentrate. With green plants, you can purify the indoor air and increase work pleasure’.
Burnout is becoming more and more common among young people between 18 and 35 years of age. Costs due to work-related stress-related absenteeism in the Netherlands amount to around €1.8 billion. Recent research shows that green rehabilitation programmes, such as hiking coaching, can reduce burnout complaints and promote reintegration.
At the same time, there are still many questions about the effectiveness of the programmes and working mechanisms, as a result of which health insurers do not recognise this form of care. The goal of Roald Pijpker’s PhD research is therefore to identify mechanisms that can explain the rehabilitation of young workers with burn-out.
In addition, it will be investigated whether programmes built on these mechanisms are actually effective. If the results are positive, the evaluated programme will be submitted to the Healthy Life Window in order to make green rehabilitation a recognized (effective) intervention available to professionals and policy makers.
Working in a green oasis therefore has its advantages: it brings moisture into the air, plants can clean the air and create a fine environment. Wageningen University & Research carried out research at three locations, where a control and intervention space were compared.
This gave striking results: after planting and hanging plants, the relative humidity improved by an average of five percentage points, in winter even by seventeen percentage points. People rated the workplace as more attractive.
The mood of employees is more positive after planting and they are more positive about their own functioning. Employees report sick less often – the drop is twenty percentage points – and people’s recovery needs are unexpectedly higher after planting.
Hermans: ‘These results are promising. That’s why research is currently being done at ten locations into the introduction of plants’ business case. After all, less artificial climate control (energy savings) or improved employee performance (labour productivity) or lower absenteeism due to sickness can result in economic savings.
A green office environment can also create an image advantage for a company and make it easier to recruit customers or staff, or to retain staff. The results of this project will be delivered in 2021′.
In addition to all the benefits, making the living environment greener can entail health risks. Think of the explosive increase of the oak processionary caterpillar or the fact that 1 in 5 tick bites are already contracted in the city.
The city is also experiencing increasing problems with water quality due to longer warm periods, causing the blue-green algae problem to increase. Researcher Bertram De Rooij: ‘Not to forget, more green also means more pollen. In urban areas there is a strong interaction between air quality and pollen, which makes hay fever problems worse’.
There are also indirect health risks in and around the urban environment related to greenery in public spaces or on and around buildings, such as fire safety.
Together with, among others, the Institute for Physical Safety and the Netherlands Fire Brigade, Wageningen is working on an integrated approach to natural fire (prevention), which now also focuses on the relationship with the urban area.
De Rooij: ‘Despite the risks, we have to be especially positive about green. In the coming years, we are going to take up the challenge of reversing the potential risks and combining them with the major positive effects of green space in order to arrive at clear, integral management and design principles. We want to interest more people in green space. After all, green space can be used in many fantastic ways’.