Grounding benefits: what earthing research shows, and what time outdoors can do

I grow much of what I eat on my farm near Durham, so the ground is part of my days. It is also one of the five plots in the Garden Check-in, where I call it Ground: time outside and movement. Grounding is a popular search, and many people in Raleigh, Durham, Chapel Hill and Cary wonder if it is real. This article goes through what the research says, where it is thin, and what is better supported.

If you want the wider picture of how daily habits affect stress, start with the guide to nervous system regulation. This post goes deeper on one habit.

What is grounding, or earthing?

Grounding, also called earthing, means direct skin contact with the surface of the earth, such as bare feet on grass, soil or sand. Indoor versions use conductive products such as mats, sheets and patches that connect to the ground through a wall outlet.¹

The idea behind it is that the earth carries a supply of electrons, and that contact with them may affect the body. Cleveland Clinic describes this as the claim of people who promote earthing, and it lists the claimed benefits as better mood and stress, sleep, pain, inflammation and immune function.¹ Those are claims, not established results.

Grounding is also a word used for something else. Cleveland Clinic's psychologist uses "grounding" as the broader term for techniques that help you refocus on the present moment, such as stretching, breathwork or engaging your senses, and sees earthing as one more specific, physical practice within it.¹ This article is about earthing.

What does the research say about grounding?

The research is small and early. Cleveland Clinic states that there is not much research on earthing, and that existing studies often have small samples, weak designs or flawed analysis, so they are too preliminary for firm conclusions.¹

Here is what the best-known papers look like when you open them.

The 2012 review. A review in the Journal of Environmental and Public Health pulled together several small studies. One was a month-long blinded pilot of 60 people with sleep problems and chronic pain who slept on a grounded or a sham mat. Another had 12 people sleep grounded for 8 weeks and compared their cortisol before and after. A third tested stress responses in 58 healthy adults.² Several of these studies were called pilots, and many outcomes were self-reported symptoms.² Three of the authors disclosed that they are independent contractors for the company that sponsors earthing research, and that they own a small share of it.² That does not make the work wrong. It does mean you should not read it as independent proof.

A 2022 sleep pilot. A small, randomized, sham-controlled trial put 22 people with mild Alzheimer's disease on a grounding mat or a sham mat for 30 minutes, five times a week, for 12 weeks. Only 15 finished, 8 in the grounding group and 7 in the sham group.³ Sleep scores were better in the grounding group at 12 weeks, but anxiety and depression scores did not differ between groups.³ In a second analysis, the sleep effect was not quite statistically significant (p = 0.053).³ The authors noted that the study was small, and that people's contact with the earth outside the study was not tracked.³

A 2022 trial in runners. Ten highly trained male runners ran in a regular shoe and in a grounding shoe, in random order, in a double-blind crossover. Running economy, blood lactate and heart rate did not differ between the shoes.⁴ The trial was funded by the shoe company, and four authors worked for it.⁴

The Sleep Foundation reaches a similar conclusion about sleep. It says studies on grounding and sleep are limited and that more robust studies are needed.⁵

Do grounding mats and sheets work?

Nobody can say yet. The evidence for mats and sheets is limited, and Cleveland Clinic notes that a 2023 review argued indoor experiments often cannot control factors such as the quality of the electrical ground connection, so a product's effect may vary widely.¹

If you are thinking about buying one, three points matter.

• The studies are small. The grounding studies described above ranged from 10 to 60 people.²³⁴
• No study described here shows that a mat changes the course of any condition. I do not make that claim, and you should be wary of any seller who does.
• There is a safety question. Sheets and mats plug into the grounded port of a wall outlet.⁵ Cleveland Clinic says earthing advocates recommend having an electrician check any outlet you plan to use, because faulty wiring could cause shock, and that these products should never be used during a thunderstorm. It adds that people with reduced feeling in their feet may not notice burns or shocks from a faulty mat.¹

My view is plain. You do not need to buy anything to try this. I would start with time outside, on real ground, before any product, and none of it replaces sleep, movement, food or care from your own doctor.

Is time outdoors good for stress?

It appears so. The evidence for time outdoors is stronger than the evidence for earthing, though most of it is observational. Time in green places is linked with lower stress markers and better self-reported health.⁶⁷⁸

Here is what the studies say.

• A small field study. In a study of 36 city residents, people spent at least 10 minutes outdoors in a place that felt like nature, at least three times a week for eight weeks. Their salivary cortisol, a stress marker, dropped more than the normal daily decline. The biggest effect appeared at 21 to 30 minutes, where cortisol fell 18.5 percent beyond the daily drop. Shorter visits of 7 to 14 and 15 to 20 minutes did not show a statistically significant change.⁶ The authors list limits: a small group, mostly women and mostly white, people who chose to take part and may already like the outdoors, and no randomization.⁶
• A large survey. Among 19,806 adults in England, spending 120 minutes or more in nature in the past week was linked with higher odds of reporting good health and high well-being. The odds ratio for 120 to 179 minutes was 1.59 for health. Less than 120 minutes was not significantly linked to either. It did not matter whether the time came in one long visit or several short ones.⁷ The design cannot show cause. Healthier or happier people may simply go outside more, and nature contact explained only about 1 percent of the variation in the outcomes.⁷
• A broad review. A systematic review of 103 observational and 40 interventional studies linked more green space with lower salivary cortisol, lower heart rate and lower diastolic blood pressure. The authors cautioned that several pooled results were limited by weak study quality and high variation between studies.⁸

The studies above measured time in green places. They do not tell us whether bare skin adds anything.

Cleveland Clinic draws a similar line. Its psychologist says connecting with nature can benefit physical and mental health, and that this is not the same as claiming earthing can prevent or cure disease.¹ The article's bottom line is that there is some evidence earthing is good for health but the claims are not backed by high-quality research, while there is a growing body of evidence that being outside, with or without touching the earth, benefits physical and mental health.¹

How can you try it safely?

Start with shoes on. Walk, sit or garden in a park, on a greenway or in your yard for 20 to 30 minutes, a few times a week. If you want to take your shoes off, pick a clean, soft, familiar patch of grass and look at the ground first.

Here is a simple way to build it into a week.

1. Pick one spot you can reach on foot or by a short drive. A yard, a park, a trail or a greenway in the Triangle all work.
2. Choose a time you already have. A lunch break or the first part of the evening works well for many people.
3. Leave the phone in a pocket. The people in the cortisol study were asked to avoid social media, the internet, phone calls, conversations and reading during their sessions.⁶
4. Move if you like, or sit if you do not. The CDC suggests that adults who are not active work up to 150 minutes a week of moderate activity, and says some brain health benefits happen right after a session.¹² Sitting still outside is fine too.
5. Start with one change. One 20-minute outing a week is a fine start. Add more later if it feels good.

If you go barefoot, these cautions apply.

• Watch the ground. Cleveland Clinic lists injury, allergic reactions and infection as risks of going barefoot, and suggests sitting or standing still if balancing on uneven ground is hard for you.¹
• Keep your tetanus vaccination current. Tetanus bacteria live in soil and enter through broken skin. The CDC recommends tetanus vaccination for everyone.¹⁰ Clean even minor cuts, and see a doctor for a deep or puncture wound or one that contains dirt or soil.¹⁰
• Do not use a mat that looks damaged, and never use one in a thunderstorm.¹

People in some groups should check with their own doctor before going barefoot. Cleveland Clinic names foot conditions, nerve damage, life-threatening insect-sting allergies, pregnancy and a weakened immune system.¹

When should you see your own doctor?

See your own doctor before trying barefoot grounding if you have diabetes, numb or tingling feet, a foot wound or a weak immune system, and sooner if stress or low mood is getting in the way of daily life. The CDC says people with diabetes should never go barefoot, because nerve damage can hide a cut or sore.⁹

Here are the specific signs to act on.

• Diabetes or numb feet. The CDC advises wearing shoes and socks or slippers, even indoors, and checking your feet every day. If you notice foot pain, tingling, loss of feeling, sores or color changes, do not wait for your next appointment.⁹
• A wound after being outside. See a doctor for a deep or puncture wound, or one with soil in it. Tetanus symptoms, which often start with jaw muscle spasms, need immediate attention.¹⁰
• A mat that sparks, smells hot or gives a shock. Stop using it and have the outlet checked.
• Medicines. The 2012 review itself noted that grounding combined with the blood thinner warfarin could add to the blood-thinning effect and should be supervised by a doctor.² If you take any blood thinner or other medicine, ask your own doctor before you rely on a grounding product. Never stop or change a medicine on your own.
• Stress or low mood that will not lift. Time outdoors is a helpful habit, not a replacement for care. If you feel sad or low most days, or it is hard to get through your day, talk with your own doctor. NIMH notes that depression can cause severe symptoms that affect how you feel, think and handle daily activities.¹¹

Call 911 for chest pain, trouble breathing, fainting or any life-threatening emergency. Call or text 988 (the 988 Suicide & Crisis Lifeline) if you are struggling or having thoughts of suicide.¹¹

A closing thought from the farm

Grounding is an interesting idea with weak evidence. Time outside has better evidence, and it is free. If you want help finding which of your five plots (Soil, Roots, Rhythm, Ground and Circle) to tend first, the Garden Check-in takes about three minutes. For quick tools that work on a hard day, see how to calm your nervous system, and for a ranked look at what else helps, see stress relief techniques.

This article is general education. It does not replace advice from your own doctor.