Monthly Archives: October 2026

Could Forest Bathing Be One of Public Health’s Most Overlooked Tools?

Could Forest Bathing Be One of Public Health’s Most Overlooked Tools?

By Thom Hartmann, educator and commentator.

Scientists are discovering that spending time in forests may help prevent disease before treatment is ever needed…

Nature is powerful medicine. Multiple studies over the years have found that people in hospitals with windows overlooking nature recover and heal faster than those without. And I remember the years when Louise and I ran a community for abused kids that was out in the woods of rural New England, it always seemed that taking them on nature walks calmed them down more than anything else, including most of the meds.

Last month, a team of researchers from six countries published an argument in Communications Health that nature should be thought of as a therapeutic tool in and of itself, and should be available to everybody. They point out that worldwide anxiety is up 63 percent and depression up 26 percent just over the past 15 years, and argue that much of this is the result of what they call “nature deprivation.”

The solution, they recommend is something called “nature-based mental healthcare” or NBMHC, citing multiple studies showing the power of regular immersion in nature as a psychological tool every bit as important and effective (and sometimes more so) as pharmaceuticals.

Ralf Buckley, the lead author, points out that more than half of all doctor visits these days are now about some aspect of mental rather than physical health, but mental health gets roughly half of one percent of public health funding.

— A 2007 study found that “forest bathing”—a Japanese concept that’s taken hold around the world, basically standing in the forest and pausing to take it all in—measurably reduces levels of cortisol, the “stress hormone.”

— A 2010 study discovered that the anti-cancer immune system “killer cells” (NK cells) in our bloodstream jacked up by exposure to nature:

“…2-night/3-day trips to forest parks enhanced human NK activity, the number of NK cells, and intracellular anti-cancer proteins in lymphocytes, and that this increased NK activity lasted for more than 7 days after the trip in both male and female subjects.”

Follow-up research found that even a one-day trip to the forest similarly increased killer cell activity, helping prevent cancer in people for at least a week thereafter.

I’ve been drawn to nature my entire life, from exploring forests and a nearby stream as a kid to Louise and my weekend trips to Portland’s Forest Park to climb the foothills of the Tualatin mountains.

And it’s not just the physical activity; when “forest bathing” is compared to working out in a gym both produce physical improvements, but the psychologically positive effects of forest bathing far outstrip those of simple exercise.

Louise and I, however, live in a city with the largest urban park in the world with over 80 miles of trails in it. And we have a good enough income to afford a car to drive to it, something many people simply can’t do.

Pointing specifically to this imbalance in access to nature caused by financial status, the authors of that first study I mentioned argue that nations should start thinking of natural spaces as part of the panoply of psychotherapeutic tools available to society, rather than decorations or recreational opportunities for people who can afford to get to them (or pay for a park pass, like in many parts of America; here in Portland, Forest Park is free).

I wrote a while back about awe being the cheapest medicine we’ve got, but cheap isn’t the same thing as accessible. In the medical context, we spend a fortune on both physical and psychological tools to repair people, but nature is almost never (other than the hospital windows studies and changes in new hospital construction) considered as a therapy.

Buckley’s team calculated back in 2019 that national parks contribute upwards of five trillion dollars a year to the global economy through the mental health benefits to visitors alone; that’s roughly five hundred times what the world spends maintaining protected areas that, it turns out, can be so critical to improving mental health (with considerable side-benefits for physical health).

Nature, it turns out, is the cheapest, safest, best-tolerated intervention in the entire mental health toolkit, but has been quietly reclassified as, essentially, a consumer good, now only available to people who have a car, a weekend, and enough disposable income.

Teddy Roosevelt understood the importance of wilderness areas instinctively and intuitively, having used nature for years to treat his own asthma and “weak constitution.” It’s why he set aside over 230 million acres of wilderness as national parks, land that sadly today’s administration is trying to sell off to donor drilling and mining operations as fast as it can.

China, on the other hand, having examined this type of research and drawing on centuries of folk medicine pointing in the same direction, has, according to researchers, a “national health strategy includes nature-therapy infrastructure in 1200 forest reserves, to provide a billion person-hours per year.”

Nature should be available to everybody, and our urban planning and policies should make sure that we have wild spaces and public transportation cheap enough to get pretty much everybody to the wild spaces.

Let your state legislators and city council know, and put together a plan to get yourself into nature at least once a week!

Copyrighted by Thom Hartmann, educator and commentator. Thom has written many respected books. Reprinted with permission from The Wisdom School of August 5th, 2026 by Thom Hartmann. All articles are free and available to everyone in The Wisdom School: What it Means to be Human. Wisdom School is a reader-supported publication. To receive new posts and support Thom’s work, consider becoming a free or paid subscriber to The Wisdom School.

Share

What If Some of Our Depression Is Coming from the Grocery Store?

What If Some of Our Depression Is Coming from the Grocery Store?

No country should have to accept a food supply that makes its people sick and sad because that’s what’s most profitable, and the science is now on our side when we say so out loud.

 
By Thom Hartmann, author, educator and commentator.
 
 

Back in the late 1970s, when Louise and I were running a residential treatment program and school for abused and emotionally disturbed kids, we took the children off the standard institutional diet. Out went the dyes, the artificial flavors, the sugary cereals and the boxed dinners, and in came real (vegetarian) food cooked fresh every day from scratch.

While it’s impossible to know how big a factor that was (we were also on a remote forest-covered lake and had some great therapists), kids who were given up on as being incorrigible or uneducatable were soon ready for reintegration into the normal school system and a foster home.

While Ben Feingold told me diet was a huge factor in kids’ behavior, and we did a small study on salicylates in their diet that I published in 1980 in the Journal of Orthomolecular Psychiatry, I was always skeptical. Until now.

Last week, researchers at UC San Francisco published a small trial in JAMA Psychiatry that looked at what happened to people clinically diagnosed with depression stopped eating ultra-processed food (UPF). For four weeks they ate a diet that cut their UPF consumption by more than 85 percent.

And, sure enough, their depression eased with their depression eased, with moderate to large improvements showing up on three separate measures. Their anxiety scores got a little better, as well.

Similarly, in 2017 an Australian team led by Felice Jacka ran the SMILES trial, taking 67 people with moderate to severe depression and giving half of them coaching toward a Mediterranean-style diet (fresh foods, mostly vegetarian/pescatarian) while the other half got supportive counseling from trained professionals. After twelve weeks, 32 percent of the food group were in full remission from their depression, compared with of the the people who just got counseling.

Two years later, researchers at Macquarie University tried a three-week version of the same study with depressed university students. The students who cut back on processed food and ate more vegetables, fish and olive oil reported significantly less depression, and the improvement was still clinically evident a full three months later.

Then came the really big large-population studies, a gold standard in health science.

Harvard researchers followed almost 32,000 nurses for decades and found that the women eating the most ultra-processed foods had about a 50 percent higher risk of developing depression than those eating the least. (Of particular interest: artificial sweeteners stood out as the worst offenders.)

A massive review in The BMJ pulled together 45 separate analyses and tied these UPF foods to 32 different kinds of harm, with anxiety and other common mental disorders at the top of the list.

And just this week another British study looked at more than 46,000 people born around the end of postwar sugar rationing. Those who spent their first thousand days of life—from the womb to their second birthday—under sugar and meat rationing were less likely to be diagnosed with depression or anxiety as adults.

Why would a bag of potato chips or too many sodas slam into your mood with such impact? The UCSF team suspects the gut-brain connection.

Their idea is that the emulsifiers, preservatives and other industrial additives in these products wear down the gut’s protective lining, which sets off low-grade inflammation that travels through the whole body and triggers a freak-out (my term, not theirs) in the brain. Dr. Nyasha Chagwedera, who led the study, put it this way:

“Junky processing may harm your gut in ways that ripple up to your brain.”

Older cultures wouldn’t find any of this surprising. They were not just careful about what they ate, but had a story about every edible plant or animal in their world; it’s how both cultural and “safe-to-eat” information was transmitted from generation to generation. And it worked until we turned our food system over to the giant corporations and their “food scientists” to figure out how to make things more profitably.

As a result, today the CDC says fully 55 percent of the calories Americans eat now come from ultra-processed products, and for our kids it’s closer to a shocking 62 percent. We—and our kids—are up against some of the most well-paid scientists and greedy capitalists on the planet.

So try this: give yourself four weeks, the same stretch the UCSF volunteers got. Read the ingredient list on everything you buy, and if it’s got anything on the list that you wouldn’t find in your own kitchen, put it back. Cook simply, and notice how you feel in week one and again in week four. And if someone you love is struggling with depression or anxiety, pass this along and offer to do it with them.

No country should have to accept a food supply that makes its people sick and sad because that’s what’s most profitable, and the science is now on our side when we say so out loud.

By Thom Hartmann, educator and commentator. Thom has written many respected books. Reprinted with permission from The Wisdom School of October 7th, 2026 by Thom Hartmann. All articles are free and available to everyone in The Wisdom School: What it Means to be Human. Wisdom School is a reader-supported publication. To receive new posts and support Thom’s work, consider becoming a free or paid subscriber to The Wisdom School.

Share