Harnessing the power of nature to extend your lifespan
One of the main aims throughout the development of human civilization has been to escape from the harsh conditions of the great outdoors into the warmth and communal comforts of urban environments. We’ve been remarkably successful too, with more people than ever now living in cities. While this has financial and social benefits, it means that it has become harder and harder for many of us to experience the sights, sounds, smells and sensations of nature.
Going extended periods without exposure to any green or open-air space has always been felt to be unhealthy, but a strong body of science now proves just how important experiences of nature are for our mental and physiological health.
The health benefits of nature
The biggest studies of how nature affects our health have looked at how peoples’ home environments impact their risk of long term degenerative diseases. For example, a large meta-analysis, including data from over 100 million people, found that greater exposure to green spaces significantly decreases the risk of death by heart disease and stroke . Other large-scale studies have shown that spending time in nature lowers blood pressure and heart rate, and can help prevent hypertension (damagingly high blood pressure) [2, 3].
There have also been numerous controlled studies comparing the effects of a walk in a natural environment against a walk of the same length in an urban environment. These have shown that walking in nature results in a significant reduction in brain activity linked to stress, depression, rumination and other negative mental traits, and can improve working memory [4, 5, 6]. Another study demonstrated that spending at least two hours a week out in nature is associated with significantly improved health and general wellbeing .
These positive effects are especially powerful if you spend most of your time in a city, since sustained exposure to the same environment is known to increase stress, while varied sensory input from a range of different environments promotes positive feelings, such as tranquillity . As such, people who visit green spaces within their cities more often are less likely to use medications for depression, anxiety, hypertension and asthma . It has also been shown that stress-related biomarkers (such as cortisol) in the saliva are directly reduced in the hours after an urban nature experience (e.g. a walk in a city park) .
We challenge you
Given all these amazing benefits, for this month’s challenge we’re encouraging you to get out in nature as much as possible and share your experience with our community, hopefully motivating you to ensure that nature experiences are a regular part of your routine.
To help guide you, we’ve devised three challenge levels based on scientific studies:
Beginner: Go for a 60-minute walk in a natural environment, such as a park, forest or beach
60 minutes of walking in nature has been shown to decrease activity in the amygdala, a brain area associated with emotional stress , while a 50-minute walk has been shown to decrease anxiety and improve working memory performance . After reviewing the literature, we think that an hour in nature is the minimum time needed to achieve many of the benefits discussed above and would make a good start for those struggling to spend enough time in nature.
Intermediate: Spend a total of two hours outside in nature during a week
A study found that people who spent at least 120 minutes a week in contact with nature were significantly more likely to have good general health and wellbeing than those who were exposed to nature for less than 120 minutes . So while an hour in nature will have a positive effect, research shows that two hours can have a much greater impact and would be a good intermediate challenge for those looking to reap more benefits.
Advanced: Spend a total of five hours outside in nature during a week
The same study discussed above found that the positive association between nature exposure and good health peaked when participants spent five hours a week outside in nature . Above five hours, benefit appears to plateau, so this is a great number to aim for in your longevity protocol.