Going outside is one of the cheapest things you can do for your body and mind, and almost all of it is free. A single walk in a green place lifts mood and eases repetitive, self-focused worrying; short spells outdoors sharpen working memory; and children who spend more of the school day outdoors become short-sighted less often. The larger claims, that people in greener neighborhoods live longer and that forest air changes the immune system, are weaker than they sound: they rest on who can afford to live near a park, or on a study of twelve men.
Almost every finding here also involves walking, and walking has stronger evidence than the setting does. Get the walk in, take the green version when you can, and skip the grounding mats.
Findings & Outcomes
What It Is
Time in nature means spending time outdoors in green or natural places: a park, a wood, a garden, a coast path, or a walk to work routed through the trees. It is among the cheapest practices on this site, and most of it is free. It is also one of the hardest to measure, because time outdoors almost always comes with a walk, with daylight, and often with company, so separating the effect of the setting from the effect of everything around it is the central difficulty in the research that follows.
What It Does
These findings are ranked by one question: how cleanly a study separates the natural setting from the walk, the daylight, and the company that usually come with it. The ladder below runs from the strongest evidence at the top down to the claims that rest mostly on who can afford to live near a park.
The strongest cause-and-effect result is about children and daylight, not trees. Adding outdoor time to the school day cut the two-year rate of childhood short-sightedness from about 27% to 23% in randomized trials, an effect of daylight and distance viewing.
Structured outdoor programs, the kind a doctor can refer you to, showed the strongest mood effect. Pooled randomized trials lifted depressed mood and positive feeling most over eight-to-twelve-week courses of 20-to-90-minute sessions, and referral schemes lowered systolic blood pressure by about 4.8 mmHg and added roughly 900 steps a day. Gardening scores well on mood, life satisfaction and weight, and time near water shows a similar signal.
The experiments that changed only the setting sit in the middle. The green version of the same walk comes out ahead on how people say they feel, while blood pressure and cortisol show no reliable difference. The cleanest single test sent healthy city-dwellers on a 90-minute walk through oak grassland or beside a four-lane road; only the grassland walkers came back ruminating less.
The largest effects rest on the weakest studies, which cannot separate the greenery from the kind of place it grows in:
- Living amid more greenery tracks lower death rates, and for children lower later psychiatric risk, but greener neighborhoods also carry higher income, cleaner air and safer streets.
- Forest bathing eases anxiety in the short term, though the studies are small and positive results are the ones that get published.
- The forest immune finding, a rise in natural killer cells, comes from a three-day trip taken by twelve men.
- Grounding, walking barefoot to draw electrons from the earth, rests on small, mostly vendor-funded studies, and does not hold up.
The Research & Studies
Everything here is based on the research we have collected and checked, sorted into groups and ordered with the strongest evidence first. Click any claim to open the studies behind it.
Longevity And Mortality
Each step up in neighborhood greenery tracks about 4% lower death risk
Across nine studies following more than eight million people, those living amid a little more greenery near home were slightly less likely to die over the follow-up, about 4% for each step up the greenness scale. It is an association, and greener areas differ from others in many ways that also affect health.
Pooling nine cohort studies of 8,324,652 people in seven countries, each 0.1 rise in satellite-measured vegetation within 547 yards (500 meters) of home carried 4% lower all-cause mortality (HR 0.96, 95% CI 0.94 to 0.97). Heterogeneity between the studies was severe and two of the nine found no association at all, so the pooled figure is a rough central tendency rather than a stable dose-response. The unit is a greenness index, not the same as living near a park, and greener neighborhoods differ from less green ones in income, air quality, noise, safety and access to care, all of which affect mortality on their own.
Who this may not transfer to:The pooled analysis does not report a sex breakdown.
Read it as a reason to plant and protect green in cities more than as something you change for yourself by moving nearer a park; the vegetation is one ingredient among income, cleaner air and safer streets, and a single reader will not shift their own risk by a satellite index.
The study · 1
Rojas-Rueda et al., green spaces and mortality, systematic review and meta-analysis of cohort studies · Lancet Planet Health 2019;3(11):e469-e477
Mood & stress
Structured outdoor programs lifted mood most over 8-to-12-week courses
Pooling the randomized trials of structured outdoor programs, mood lifted and positive feeling rose, most over eight to twelve weeks of short sessions. Physical-health measures barely moved.
Across the 16 randomized trials inside a review of 50 studies, structured outdoor nature activities improved depressed mood (SMD -0.64, 95% CI -1.05 to -0.23) and positive affect (SMD 0.95, 95% CI 0.59 to 1.31), with a large but statistically fragile effect on anxiety (SMD -0.94, upper CI near zero) and a smaller effect on negative affect (SMD -0.52). Programs of 8 to 12 weeks with 20-to-90-minute sessions did best, and physical health outcomes moved much less. Risk of bias was low to moderate in the randomized subset and moderate to high in the 34 non-randomized studies. Every program bundles the outdoors with exercise, a group, a leader and a routine, and none of the trials separates the setting from the rest of the package.
Who this may not transfer to:The review reports no pooled sex breakdown across its 50 studies.
Build in the whole package, the routine, the movement and the group, rather than expecting the setting alone to lift mood; that is the form the evidence actually tested.
The study · 1
Coventry et al., nature-based outdoor activities for mental and physical health, systematic review and meta-analysis · SSM Popul Health 2021;16:100934
The least childhood greenery tracked up to 55% higher later psychiatric risk
Following nearly a million Danes, children who grew up with the least greenery nearby carried up to 55% higher risk of a later psychiatric disorder than those with the most, after adjusting for family income and history. Two of the conditions looked at showed no link.
943,027 Danes born 1985 to 2003, with satellite greenness measured around every childhood address up to age 10. Those in the lowest green-space band carried up to 55% higher risk of later psychiatric disorders than those in the highest, strongest for depression and stress-related disorders, after adjustment for parental income, education, employment, psychiatric history and urbanization. Cumulative green space across childhood predicted more strongly than any single year, which fits an accumulating exposure and also fits a stable family staying in one place. Intellectual disability and schizoaffective disorder showed no clear association, and the authors still name green-space quality, crime rates and neighborhood disadvantage as unmeasured.
Who this may not transfer to:Sex was adjusted for in the models; results are not reported separately for men and women.
It is a strong argument for green in the places children grow up; where a family lives is not random, so read it as an advantage of greener neighborhoods rather than a dose you can prescribe.
The study · 1
Engemann et al., residential green space in childhood is associated with lower risk of psychiatric disorders from adolescence into adulthood · Proc Natl Acad Sci U S A 2019;116(11):5188-5193
120 minutes a week in nature tracks better self-rated health and wellbeing
In a large English survey, people who spent at least two hours a week in nature reported better health and wellbeing than people who spent none, and it made no difference whether that came as one long visit or several short ones. The benefit stopped climbing past three to five hours.
A nationally representative survey of 19,806 adults in England. Compared with no time in nature, 120 minutes a week or more was associated with better self-reported health (OR 1.59) and wellbeing (OR 1.23), plateauing between 200 and 300 minutes, with no difference between one long visit and several short ones. It is a single cross-sectional snapshot with both exposure and outcome reported by the same person, so healthier people getting outside more explains part of it. The association held among older adults and people with long-term conditions, and survived adjustment for local green space, neighborhood, physical activity and demographics.
Who this may not transfer to:Sex was adjusted for but no breakdown is reported.
Treat 120 minutes a week as a reachable target rather than a proven threshold, and split it however the week allows, since short visits added up as well as one long one. The snapshot cannot show the time outdoors caused the health.
The study · 1
White et al., spending at least 120 minutes a week in nature is associated with good health and wellbeing · Sci Rep 2019;9(1):7730
The green setting adds to mood, but not to blood pressure or cortisol
When researchers had people do the same walk or run in a green place and in a built-up one, the green setting came out ahead on how people said they felt, while blood pressure and stress hormone showed no reliable difference and an attention edge faded once the groups were matched.
Of 25 included studies, most compared the same activity, usually a walk or run, in a natural setting against a built or indoor one. Pooled self-reported emotion favored the natural setting; the attention advantage did not hold after adjusting for pre-walk differences between groups, and blood pressure and cortisol showed no consistent difference. Nobody can be blinded to which environment they are in, and the outcome that moved most is the self-reported one, the most open to expectation. The review dates from 2010, and the design problem it named is still present.
Who this may not transfer to:The review does not pool a sex breakdown across the 25 included studies.
The setting adds something to mood, and the walk carries the rest, with much stronger evidence behind it, so prioritize getting the walk in and take the green version when you can.
The study · 1
Bowler et al., systematic review of evidence for the added benefits to health of exposure to natural environments · BMC Public Health 2010;10:456
Time near water leaned toward better wellbeing across 35 studies
Across thirty-five studies of lakes, rivers and coast, time near water leaned toward better mental wellbeing and more physical activity, while general health and heart measures were mixed. Nothing could be pooled because every study measured it differently.
Thirty-five quantitative studies of lakes, rivers, canals and coast, mostly European. The balance of evidence favored better mental health and wellbeing (12 studies) and higher physical activity (13 studies), with general health, obesity and cardiovascular outcomes less consistent. No pooling was possible because exposure was measured differently in almost every study, from straight-line distance to the coast to self-reported visits, and coastal and waterside housing tracks income the way green neighborhoods do. The reviewers call for longitudinal work before causation is read into it.
Who this may not transfer to:The review does not pool a sex breakdown across the 35 included studies.
The study · 1
Gascon et al., outdoor blue spaces, human health and well-being, a systematic review of quantitative studies · Int J Hyg Environ Health 2017;220(8):1207-1221
Gardeners scored better on mood, weight and life satisfaction across 22 studies
Pooling twenty-two studies, gardeners scored better on mood, life satisfaction and body weight. Signs of publication bias were present and the effect shrank after correction, and gardening brings physical work, daylight and often company along with the plants.
Twenty-two studies giving 76 comparisons found a positive pooled effect of gardening across a wide spread of outcomes, including lower depression, anxiety and body mass index, and higher life satisfaction and sense of community. Egger's test detected publication bias, and the effect held at a smaller size after a trim-and-fill correction. Many comparisons are before-and-after in the same people with no control group, and gardening supplies physical work, daylight and often company alongside the plants.
Who this may not transfer to:About 68% female, mean age 52.
Read gardening as one of the richer versions of time outdoors, since it loads the body and usually adds company, rather than as an effect of the plants by themselves.
The study · 1
Soga, Gaston and Yamaura, gardening is beneficial for health, a meta-analysis · Prev Med Rep 2016;5:92-99
A 90-minute grassland walk lowered rumination where the same road walk did not
Healthy city-dwellers who took a 90-minute walk through grassland came back dwelling less on their problems, while those who walked the same distance beside a four-lane road did not, with a matching change in a brain region tied to brooding. It was one walk each and no follow-up.
38 healthy urban adults, 18 of them women, mean age 27, randomly assigned to a 90-minute 3.3 mile (5.3 km) walk through oak grassland or along a four-lane road. Self-reported rumination fell in the grassland group and did not change in the road group, and blood perfusion in the subgenual prefrontal cortex fell alongside it. Heart rate and respiration did not differ between groups, so the effect was not a difference in exertion. Nineteen people per group, one walk, no follow-up, so it says nothing about a lasting change, and rumination was self-reported by people who knew which walk they had taken.
Who this may not transfer to:Results are not reported separately for the 18 women and 20 men.
The study · 1
Bratman et al., nature experience reduces rumination and subgenual prefrontal cortex activation · Proc Natl Acad Sci U S A 2015;112(28):8567-8572
Forest bathing eased anxiety short-term across 20 studies, with publication bias
Pooling twenty studies, an unhurried forest visit reduced symptoms in the short term, clearest for anxiety. The studies are small and short, and the reviewers found that positive results were more likely to be published, so the real effect is probably smaller.
Twenty studies covering 2,257 participants, most in Asia and Europe. Shinrin-yoku reduced symptoms in the short term, with the clearest signal on anxiety and a weaker one on depression, and no study followed participants beyond a few weeks. The authors found indications of publication bias in nearly every analysis they ran, and the included studies are small, short and mostly without an active comparison, so the pooled figures likely sit above the true effect.
Who this may not transfer to:The review does not pool a sex breakdown; several of the largest included studies used men only.
The study · 1
Kotera, Richardson and Sheffield, effects of shinrin-yoku (forest bathing) and nature therapy on mental health, systematic review and meta-analysis · Int J Ment Health Addict 2022;20:337-361, published online 2020
Surgery patients facing trees left hospital sooner, across 23 matched pairs
In a much-quoted 1984 study, surgery patients whose room faced trees went home a little sooner and asked for fewer strong painkillers than matched patients facing a brick wall. It was 23 pairs at one hospital, drawn from old records, and has not been repeated at scale since.
Records of 46 gallbladder-surgery patients at one suburban Pennsylvania hospital between 1972 and 1981, matched into 23 pairs. Patients whose window faced trees left hospital sooner, took fewer strong painkillers, and drew fewer negative comments in nurses' notes than their matched pair facing a brick wall. Room assignment was not random; which room a patient got depended on what was free when they arrived, and rooms that face grounds differ from rooms that face a wall in ward position, noise and light as well as view. It is quoted far more often than anything else in this field and has not been repeated at scale in the four decades since.
Who this may not transfer to:The paper does not report the overall sex split of the 46 patients.
The study · 1
Ulrich, view through a window may influence recovery from surgery · Science 1984;224(4647):420-421
Cognition
Time in nature gave a small lift to working memory across 42 studies
Across dozens of studies, time in natural settings gave a small-to-moderate lift to working memory and mental flexibility, with real places beating photos and video. Most tests were brief lab tasks rather than a change across a working day.
Pooling 49 outcome measures from 42 studies across eight cognitive domains, exposure to natural environments improved working memory and cognitive flexibility at low to moderate effect sizes, with attentional control less reliable and the other five domains flat. Real places produced larger effects than photographs or video, though the real-place exposures also ran longer, which the authors say they cannot separate from the setting. Most exposures last minutes and the outcomes are laboratory tasks, so this does not show a change in how someone works the next day.
Who this may not transfer to:The pooled analysis reports no sex breakdown; the underlying samples are mostly university students.
Use a short spell outside to reset tired attention; the effect is modest and measured over minutes, so treat it as a break rather than a substitute for rest or sleep.
The study · 1
Stevenson, Schilhab and Bentsen, Attention Restoration Theory II, systematic review and meta-analysis · J Toxicol Environ Health B Crit Rev 2018;21(4):227-268
Vision
Extra outdoor time cut two-year child myopia from 26.7% to 22.5%
Adding time outdoors to the school day cut the share of children becoming short-sighted over two years from about 27% to 23%. This is the strongest cause-and-effect finding on the page, and it is about daylight and looking at distant things rather than about trees.
Five randomized trials, four randomized by school, covering 10,733 children aged six to nine. Adding outdoor time cut two-year myopia incidence from 26.7% to 22.5% (RR 0.84, 95% CI 0.72 to 0.98) and slowed the refractive shift by 0.13 diopters over two years; the single three-year trial reported 30.5% against 39.8%. Certainty was moderate at two years and the three-year result rests on one trial, and neither children nor teachers can be blinded to extra time outside. The exposure is daylight and distance viewing rather than woodland.
Who this may not transfer to:All five trials were run in East Asia, where baseline myopia rates are much higher than in Europe or North America.
For children, protecting daily outdoor time is well worth it for the eyes; all five trials ran in East Asia, where short-sightedness is far more common, so the size of the gain elsewhere may differ.
The study · 1
Kido, Miyake and Watanabe, interventions to increase time spent outdoors for preventing incidence and progression of myopia in children (Cochrane review) · Cochrane Database Syst Rev 2024;6(6):CD013549
Heart And Vascular
Nature prescriptions lowered systolic blood pressure 4.8 mmHg and added about 900 steps a day
When a doctor or social worker referred people to an outdoor program, blood pressure fell a few points, depression and anxiety scores improved, and people walked about 900 more steps a day.
Ninety-two studies identified, 28 pooled. Referral programs lowered systolic blood pressure by 4.8 mmHg (95% CI -8.9 to -0.7) and diastolic by 3.8 mmHg, improved depression scores (SMD -0.50) and anxiety scores (SMD -0.57), and added about 900 steps a day (95% CI 790 to 1,010). Most included studies carry a moderate to high risk of bias, the programs range from a walking group to a therapeutic garden, and someone who accepts a referral to spend time outdoors differs from someone who declines one.
Who this may not transfer to:The review reports no pooled sex breakdown across the 28 studies contributing to meta-analysis.
If your health service offers a nature or green-social prescription, it is a low-risk thing to accept; the gains ride on the exercise, routine and company built into the programs as much as on the setting.
The study · 1
Nguyen et al., effect of nature prescriptions on cardiometabolic and mental health, and physical activity, systematic review and meta-analysis · Lancet Planet Health 2023;7(4):e313-e328
Counts once: this finding and 1 other here come from the same source, so they are one body of evidence, not separate confirmations.
Behavior Change
Weekly minutes of moderate activity did not rise under nature prescriptions
In the same programs, device-counted steps rose by about 900 a day while questionnaire-recalled weekly exercise did not budge. The two measures disagree because one is counted and one is remembered.
In the same review, weekly time in moderate physical activity did not improve (mean difference 25.9 minutes, 95% CI -10.3 to 62.1), while daily step counts in the same programs rose by about 900. The two disagree because steps usually come from a device and weekly moderate activity is usually recalled on a questionnaire; either the added walking sat below moderate intensity or the questionnaires did not capture it.
Who this may not transfer to:No pooled sex breakdown is reported for the physical activity outcomes.
Trust the step count over the recalled minutes; the extra walking was real, it may simply have sat below what people label as exercise.
The study · 1
Nguyen et al., effect of nature prescriptions on cardiometabolic and mental health, and physical activity, systematic review and meta-analysis · Lancet Planet Health 2023;7(4):e313-e328
Counts once: this finding and 1 other here come from the same source, so they are one body of evidence, not separate confirmations.
How it works
Grounding and earthing rest on small, mostly vendor-funded studies
Small studies report changes in blood and inflammation markers after bare skin touches the ground, but the samples are tiny and much of the work comes from people who sell grounding products. Walking barefoot on grass is pleasant and harmless; the electrical claim behind the products is not settled.
The measured literature is individual studies of eight to fifty-eight people, mostly pilots, reporting changes in inflammation markers, heart-rate variability and blood measures after skin contact with the ground or a grounded surface. A large share comes from the same few authors, and several of the review authors have financial ties to a company that sells earthing products and funded the research. The specific electron-transfer mechanism has not been tested at any scale that would settle it.
Who this may not transfer to:Sex is reported for only one of the underlying studies, which used eight men aged 20 to 23.
Walk barefoot on grass or sand for the pleasure of it and watch where you step; there is no need to buy a grounding mat or sheet on the current evidence.
The study · 1
Chevalier et al., earthing, health implications of reconnecting the human body to the Earth's surface electrons · J Environ Public Health 2012;2012:291541
Salivary cortisol ran lower after a forest visit, and lower still before it began
Salivary cortisol, a stress marker, was lower in forest groups than city groups after a visit, but it was already lower before anyone entered the forest, by a wider margin. Groups that differ at the start cannot tell you much about the forest.
Eight studies pooled out of 22 reviewed. Salivary cortisol was lower in forest groups than urban groups after the visit (MD -0.05 ug/dl, 95% CI -0.06 to -0.04), and also lower before the visit began (MD -0.08 ug/dl, 95% CI -0.11 to -0.05), a larger gap. The groups already differed before anyone entered a forest, the review's own authors attribute part of the effect to anticipation, and heterogeneity after the intervention was 88%.
Who this may not transfer to:The pooled studies do not report a combined sex breakdown, and single-sex male samples are common in this literature.
Take the stress-hormone forest claims lightly; the design cannot separate the forest from who chose to be there and what they expected of it.
The study · 1
Antonelli, Barbieri and Donelli, effects of forest bathing (shinrin-yoku) on levels of cortisol as a stress biomarker · Int J Biometeorol 2019;63(8):1117-1134
Immune Function
Natural killer activity rose about 50% after a three-day forest trip
Twelve men on a three-day forest trip showed a roughly 50% rise in natural killer immune cells that lasted over a week, with no rise on a matched city trip, and tree compounds were measurable in forest air. It is twelve people, unblinded, from one research group, and no study has shown the cell change alters anything a person notices.
Twelve healthy Japanese men aged 35 to 56 took a three-day forest trip and, separately, a matched three-day city trip. Natural killer activity rose about 50% after the forest trip and stayed raised more than seven days, did not rise after the city trip, and urinary adrenaline fell after the forest trip only. Alpha-pinene and beta-pinene were measurable in forest air and near-absent in city air. Twelve people, no randomization, no blinding, fixed trip order, and almost the entire body of this work comes from one group at Nippon Medical School; a companion study in 13 nurses found the same rise in women without a city comparison. A three-day trip away from a Tokyo office differs from an ordinary day in many ways besides the trees, and natural killer activity is a laboratory measure.
Who this may not transfer to:A separate study by the same group in 13 Japanese nurses aged 25 to 43 found the same rise in natural killer activity, without a city comparison trip.
This is the most repeated and the thinnest claim on the page; take a forest trip on its own merits rather than for a laboratory immune number.
The studies · 2
Li et al., visiting a forest, but not a city, increases human natural killer activity and expression of anti-cancer proteins · Int J Immunopathol Pharmacol 2008;21(1):117-127
Li et al., a forest bathing trip increases human natural killer activity and expression of anti-cancer proteins in female subjects · J Biol Regul Homeost Agents 2008;22(1):45-55
How It Works
Several things happen at once when you go outside, which is why the setting is so hard to score on its own:
- Daylight reaches the eyes and sets the body clock, the subject of the morning light page.
- The body moves, and walking by itself has a large, well-measured effect on mood, blood pressure and how long people live, covered on the walking page.
- Attention gets a rest, because a natural scene occupies the eye without much effort and lets the directed, effortful kind of attention recover.
- A structured outdoor session usually adds other people.
Anatomy of the Practice
1The first minutes
You step outside and daylight reaches your eyes. Mood lifts and repetitive, self-focused thinking eases, because a natural scene occupies attention without much effort. This is the change a single short visit delivers.
2Over a session
Twenty minutes to an hour or two outdoors brings movement, daylight and often company along with the setting. Mood improves, blood pressure eases a little, and the day gets broken up. Most of the measured effect comes from the walk; the setting adds to reported mood.
3Over months and years
Living where nature is close tracks lower psychiatric risk in childhood and lower death rates in adults. This accumulates slowly and is bound up with who can afford to live near a park, so it reads best as an advantage of greener places, with the greenery one ingredient among several.
Because a forest walk measured against sitting indoors captures all of that at once, the studies to read first are the ones that held the activity constant and changed only the setting. Pooling twenty-five such studies, the same walk or run done among trees came out ahead of one done in a built-up place on self-reported mood, while blood pressure and cortisol showed no consistent difference, and an early attention advantage faded once the groups were matched for how they differed beforehand.
The best-controlled single experiment held distance and effort equal across a 90-minute walk through oak grassland or beside a four-lane road, and only the grassland walkers came back ruminating less. That is a small number of people and one walk each, and it is still the best available answer to what the setting adds by itself.
The largest signal in the field is residential, and it is the most confounded. Greener neighborhoods also carry higher income, cleaner air, less traffic noise, safer streets and better access to care, and every one of those affects health on its own. Studies adjust for what they can measure, and income and education are captured crudely next to how strongly they shape a life, so part of the green-space advantage is an advantage of the kind of place greenery tends to come with. That makes the residential data a strong argument for planting cities and a weak one for any single reader, who will not change their own risk by reading a satellite index.
The walk carries most of the measured benefit and has far stronger evidence than the setting. Prioritize the walk, and take the green version when it is there.
Getting Outside
Ways to Do It
Nothing here is bought or built. A walk in a park is free, and what changes between the rungs is the dose and the kind of nature, from a few minutes at a window to a standing weekly visit. Start wherever your week already has room and add from there.
Take your break outside instead of at your desk, and sit where you can see something green if you can. A window facing a tree is the smallest version anyone has studied, and even a few minutes of daylight and weather counts. The first coffee taken on the step gets you this and the body-clock benefit of [morning light](/go/integrative/practice/morning-light) at once.
Route an ordinary walk, the commute or a phone call taken on foot, through the nearest green: a park, a canal path, a cemetery, a tree-lined street. The green-space research measures vegetation within 547 yards (500 meters) of a front door, so a square or a row of street trees counts as the thing that was studied. Where you can, keep to the greener side away from heavy traffic, since cleaner air carries part of the benefit.
A weekly hour or two in a wood, a large park or by the water, walked slowly with attention on what you can see, hear and smell. This is the unhurried forest visit the Japanese call shinrin-yoku, and it is also roughly the 120 minutes a week that a large survey linked with better self-rated health. One long visit and several short ones worked equally well, so split it however the week allows.
A plot on an allotment, a gardening group, a walking club, a conservation morning, or a program your doctor can refer you to. Gardening adds physical work, and structured outdoor programs are where the randomized mood trials and the rise in daily step counts show up. The company is part of why they work, which the [connection and belonging](/go/integrative/practice/social-connection) page covers.
Go Deeper
- Walking: the part of almost every nature study that has the strongest evidence of its own, and the thing to prioritize.
- Morning light: the daylight half of going outside, and how it sets the body clock.
- Connection and belonging: the company that most group outdoor programs are also delivering.
- Depression: where outdoor activity sits among the things with better evidence behind them for low mood.
The Chinese Medicine View
Yang Sheng, 養生, nourishing life, puts living in step with the natural world at the center of health, and the tradition's founding text opens with it. The second chapter of the Suwen gives conduct for each season:
- In spring, rise early and walk in the courtyard with the hair loose and the body unhurried.
- In summer, rise early and let the Qi move outward without resenting the long day.
- In autumn, sleep earlier and gather the mind inward.
- In winter, sleep early and rise late, wait for the sun, and keep the pores closed.
Getting outside is not a modern discovery here, and it is conditional: the counsel is as much about when and how as about whether.
Wind, Cold, Damp, Summerheat, Dryness and Fire are the six external factors, 六淫, the tradition's account of the outdoors turning into illness. The picture it treats as risky is a specific one, sweating with the pores open in a cold wind, or long sitting on cold wet ground, not time outdoors in itself. Read as description rather than mechanism, this is an account of dose and timing arrived at by observation, and it agrees with the modern reading in some places and not in others.
The tradition parts from the modern enthusiasm most clearly in winter, where it counsels conserving, rising after the sun and avoiding a sweat, which runs counter to a January dawn-hike and cold-plunge routine. It also treats the same weather differently for different people. Someone who runs cold, tires easily and feels heavy and foggy in humidity is the constitution it would keep warm and dry and out of the damp, while someone with heat signs and a restless Shen does better in shade and the early morning than in midday sun. Neither system validates the other.
Cautions For This Practice
Everything to be aware of is here, in one place. This practice suits most healthy people; a few situations call for real care.
Sun: the same hour can burn
The hour outdoors that gives you daylight can also give you sunburn, and sunburn is the exposure most associated with melanoma risk. Ultraviolet is strongest between roughly 10am and 4pm, and stronger again at altitude, near the equator, and reflected off water, sand and snow. Cover up, use shade, and use sunscreen on what stays bare. Daylight for the body clock works through the eyes and needs no burn: even an overcast morning outdoors delivers far more light than any indoor room.
Ticks in long grass and woodland
In wooded and long-grass country across much of Europe, North America and northern Asia, ticks can carry Lyme disease and, in some regions, tick-borne encephalitis. Walk the middle of the path, tuck trousers into socks, and check the whole body when you get home, including the scalp, behind the knees, the groin and the waistband. Transmission usually takes many hours of attachment, so removing a tick the same day matters. Grip it close to the skin with fine-tipped tweezers and pull straight out, and see a doctor for an expanding rash, or for fever, headache or joint pain in the weeks after a bite.
Heat on long summer walks
Long walks in hot, humid weather can bring on heat exhaustion or heat stroke, and the risk runs higher for older adults, young children, anyone with heart or kidney disease, and anyone taking diuretics, anticholinergics, beta-blockers or antipsychotics. Go early or late, carry water, rest in shade, and stop at dizziness, nausea, headache or a sudden halt in sweating.
Cold, wind and wet
Wet and windy is harder on the body than dry and cold. Cold air raises blood pressure and can bring on angina, so anyone with Raynaud's, peripheral vascular disease or a heart condition has reason to dress for it and take care. The traditional caution against sitting on cold, wet ground is a sensible one for anyone prone to stiff, achy joints.
A few more, by situation
Pollen can set off hay fever and asthma in season; poor air-quality days are a reason to stay in for anyone with lung disease; uneven ground calls for care from anyone unsteady on their feet, which the [balance and falls](/go/integrative/practice/balance-and-falls) page covers; and tell someone your route if you are walking alone somewhere remote.
Start slow, be smart, read the research, and consult a professional if you have any concerns. This is here to inform your choice, not make it for you.
Common Questions
How much time in nature do I need?
The much-quoted figure is 120 minutes a week, from a survey of 19,806 English adults in which that amount marked better self-reported health and wellbeing than none at all. The benefit leveled off between 200 and 300 minutes, and splitting it across several short visits worked as well as one long one. The survey was taken at a single point in time, so it can show the link but not that the time outdoors caused the health.
Does forest bathing actually do anything?
Short-term mood and anxiety improve in the pooled studies, with signs of publication bias in most of the analyses, so the true effect is probably smaller than the figures suggest. The famous immune findings, natural killer cells and tree volatiles, come from studies of twelve men run by one research group, without randomization or blinding. Going for an unhurried walk in a wood is a fine thing to do on much simpler grounds.
Is it the nature or the walking?
Mostly unseparated. The reviews that held the activity constant found the natural setting added something to self-reported mood, no consistent difference in blood pressure or cortisol, and an attention advantage that did not survive adjustment. Walking on its own has far stronger evidence than the setting does, so the walk is the part to prioritize, and the green version is the one to take when you can.
Does grounding or walking barefoot have evidence behind it?
The measured studies are small, mostly from the same authors, and several are funded by a company that sells grounding products whose staff are among the authors. Walking barefoot on grass or sand is free and safe if you watch where you step. The specific electrical mechanism has not been tested at a scale that would settle it, so there is no need to buy a mat on what is known so far.
What if I live in a city with no forest?
You are already looking at what was studied. A park, a campus, a canal path, a cemetery, street trees, a window facing a tree. The green-space cohorts measure vegetation within 547 yards (500 meters) of home, and the best-controlled walking experiment used oak grassland at the edge of a suburb. Route around heavy traffic where you can, since air quality carries part of the benefit.
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Thomas Dehli, Founder & Editor, Sacred Lotus
Sacred Lotus has published Chinese medicine reference material since 2001. Integrative pages are held to the same standard as the herb and formula library: cite the source, grade the claim at its real strength, and say where the research has not looked. This page is educational and it is not medical advice. Last reviewed and updated August 9, 2026.
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