Why being outdoors can make you healthier and happier
Looking for an easy way to improve your health? Spending time in nature might be the answer
Hi there,
It’s sunny and warm (19 degrees!) in London today. For many, this will be the first time in a while that they’ve decided to spend time outside, emerging from winter hibernation to feel the warming rays of the sun.
Our modern, screen-centric lifestyles mean that we don’t often experience nature.
On average, we spend 90% of our time indoors. I’ve always enjoyed hiking and being outdoors, but I can see how this happens. For years my day-to-day involved being at home or work, on the tube, and in pubs and restaurants - with brief moments outside between locations.
This changed in 2020.
During lockdown, I started going for walks. The fresh air, spring sunshine, and awkward attempts to maintain a 2 metre distance from other people provided a temporary escape from the loneliness of my flat. I always returned home feeling better.
Lockdown is over, but my walking habit (some say obsession) continues. In trying to convince people to join me, I’ve discovered the prospect of going for a walk doesn’t fill everyone’s heart with joy.
Am I just being weird? Should I stop coercing my loved ones to go for a walk with me? What does the science say?
The benefits of being outdoors
A lot of research has been conducted on the benefits of being in nature.
A systematic review of 143 studies showed that exposure to green spaces is associated with a variety of health benefits. This includes improved health stats (lower blood pressure, cholesterol, cortisol, heart rate, and heart rate variability), as well as lower incidence of disease (type 2 diabetes, stroke, hypertension, and coronary heart disease). This is compelling evidence that benefits exist, but doesn’t explain why.
Here are three ways that being in nature improves our health and well-being, looking at what happens in our bodies when we go outside:
Feel happier
Have you ever felt like you’re happier when the sun’s out?
Serotonin is a neurotransmitter that has a positive impact on mood, emotions and sleep. A review on how to increase serotonin in the human brain without drugs found that exposure to sunlight is associated with higher serotonin levels in the brain.
If you live in the UK and go weeks without seeing the sun, all hope is not lost.
You can benefit from natural light even if the forecast is cloudy. Light levels outside can be greater than 1000 lux even when it’s overcast (much higher than you’d typically get indoors).
Another benefit of sunlight exposure is that it triggers our bodies to produce vitamin D. This is important for a variety of reasons, including impacting our mood. Studies (like this one) suggest that vitamin D deficiency can be linked to depression.
Reduce stress
Research shows that being outside can help you feel less stressed.
Cortisol is the body’s main stress hormone. A 2019 study showed that after spending time outside, people’s cortisol levels dropped (21.3%/h beyond the typical 11.7%/h daily drop). The most benefit per time spent was seen after about 20-30 minutes being outside. Cortisol levels continue to drop with more time spent outside, but at a reduced rate.
Another study on deprived communities showed similar findings.
Improve sleep
Getting outside and viewing natural light has been shown to improve the quality and duration of sleep. This is because the cells in your eyes need this light to wake up your circadian clock.
This is the suggested protocol for using light exposure to improve sleep from Dr. Andrew Huberman (more on this in his podcast on light and circadian rhythms):
Go outside within 30-60 minutes of waking up
Go outside again in the late afternoon, prior to sunset
On bright, cloudless days doing this for 10 mins is sufficient. On cloudy days you’ll need 20 mins and on very overcast days 30-60 mins.
How long do you have to spend outside?
Those of you who don’t love the outdoors may be wondering how long you have to endure nature to reap the benefits.
One study of almost 20,000 people (a representative sample of the adult population of England) showed that spending at least 120 minutes a week in nature is associated with better health and well-being. The key findings:
The benefits peaked around 200-300 minutes and then plateaued
It didn’t matter whether it was a long period or a few shorter periods of being outside - the total time was the important factor
Less than 120 minutes a week was essentially the same as nothing
This pattern was consistent across a variety of demographic factors: urban or rural environment, age, deprivation, gender, if you had a long-term illness or disability, and whether or not you performed the generally recommended amount of physical activity.
Question of the week
Improving your health isn’t always easy.
Eating well and developing exercise habits are important, but they can be difficult. Getting outside won’t miraculously give you abs, but it’s one small, achievable step towards a healthier, happier life.
With that, my question: what’s one thing you currently do inside that you could do outside?
Link of the week
One of my favourite podcasts is Steven Bartlett’s ‘Diary of a CEO’, and his episode with Israel Adesanya was one of the best I’ve heard recently.
But I almost didn’t listen to it.
If you’ve never heard of Adesanya, you’re not alone - I hadn’t either. Glancing at the description, I discovered he’s the UFC middleweight champion - I’m not particularly interested in MMA. In the past, I would have skipped an episode like this, but I’m glad I didn’t.
Adesanya has a refreshing take on life and makes funny, interesting observations about how we behave. Here’s one of my favourite bits, on being a role model (20-second clip).
That’s all for now. Have a wonderful week!