Nature exposure that fights stress

Unemployment, work strain, financial constraints and dysfunctional social networks are some of the challenges afflicting people in urban areas, especially busy cities like Nairobi.

Without adequate coping mechanisms, these pressures take a toll on people, enhancing production of a stress hormone known as cortisol that contributes to mental health problems like anxiety, depression and low moods.

Affected individuals often seek services from mental health experts such as psychiatrists and psychologists.

In most cases, medication will be required. It comes at a cost.

For individual grappling with financial constraints and unable to afford the recommended care, the situation is usually dire.

Such people suffer in silence as the ailments render them unproductive in the society.

To address these challenges and nip stress in the bud before it progresses to mental illness, health experts are advising use of nature that comes without or little financial implications.

A new study published in the Frontiers in Psychology Journal says taking at least 20 minutes daily to stroll or sit in a place where one is in contact with nature significantly lowers the stress hormone levels.

The research is the first to establish the optimum dose of nature required by urban dwellers for mental health benefits.

"We know that spending time in nature reduces stress, but until now it was unclear how much is enough, how often to do it, or even what kind of nature experience will benefit us," says Mary Carol Hunter, lead author of the study and associate professor at the University of Michigan.

She stated: "Our study shows that for the greatest payoff, in terms of efficiently lowering levels of the stress hormone cortisol, you should spend 20 to 30 minutes sitting or walking in a place that provides you with a sense of nature."

In a country where approximately one out of every four people suffer from mental illness, such stress management can come in handy for most Kenyans.

During the study, the overarching goal for the researchers was to assist healthcare practitioners looking for evidence-based guidelines on the amount of nature time that can be prescribed to patients for the management of stress and other mental health challenges.

As such, Hunter and her colleagues designed an experiment that would give a realistic estimate of an effective nature dose.

Over an eight-week period, participants were asked to spend time in nature for the duration of 10 minutes or more, at least thrice weekly.

Thereafter, levels of the stress hormone cortisol were measured from saliva samples taken before and after the interaction with nature, once every two weeks.

Participants were at liberty to choose the time of day, duration, and the place of their nature experience.

The location could be anywhere that participants feel like they had interacted with nature.

To minimise factors known to influence stress, the participants were required to interact with nature in daylight and avoid performing aerobic exercises, using social media, browsing the Internet, making phone calls, engaging in conversations or reading as they spent time in nature.

"We accommodated day to day differences in a participant's stress status by collecting four snapshots of cortisol change due to nature," says Dr Hunter.

"This also allowed us to identify and account for the impact of the on-going, natural drop in cortisol levels as the day goes on, making the estimate of effective duration more reliable."

To make it attuned to real life settings, the study was designed to allow for flexibility that incorporates participants’ hectic schedules as well as the specific times and places they chose for their nature experience.

The study revealed that just a twenty-minute nature experience was enough to significantly reduce cortisol levels.

But for those that spent a little more time immersed in a nature experience, such as 20 to 30 minutes sitting or walking, cortisol levels dropped at their greatest rate.

Dr Hunter notes that the results of the study provide the first estimates of how nature experiences impact stress levels in the context of normal daily life.

It breaks new ground by addressing some of the complexities of measuring an effective nature dose that would guide doctors seeking to recommend it as a therapy for fighting stress and other mental health challenges.

"Healthcare practitioners can use our results as an evidence-based rule of thumb on what to put in a nature-pill prescription," she says.