Have you heard of 'grounding' or 'earthing'? What it is and why it's getting attention.

Jeannie Sindicic remembers being just 4 or 5 years old when she would feel a sense of calm and belonging by simply planting her bare feet on the Earth.

"I loved being barefoot. Anytime I was barefoot – walking on soil, walking on grass – it made me personally feel at a very young age very connected to Mother Earth," she says, recalling how her grandmother would tell her anytime you're barefoot on the ground you're "vibrating with the natural frequency of the earth and the benefits of what that was."

It wasn't until much later that Sindicic, now an intuitive life coach based in the Midwest, learned the name for this very practice: earthing.

"We would call it grounding," she says, another term people still use for it today.

And she is far from alone.

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Earthing, or grounding, is a practice that has likely existed in certain communities for generations even if there wasn't an exact label for it. Now, thanks to an interest in natural healing and further discoveries in this area, the practice is gaining more attention. On social media platforms like TikTok, the hashtag #earthing has more than 66 million views and #grounding has 199 million. The 2019 documentary "The Earthing Movie: The Remarkable Science of Grounding" has 4.6 million views on YouTube.

What exactly is 'earthing'?

Clint Ober, author of "Earthing: The Most Important Health Discovery Ever?" and earthing expert, explains earthing has to do with the Earth's slight negative charge and abundance of free electrons.

"Anything that is conductive (like a ground rod, metal, a human body, an animal) that touches the earth, the body absorbs electrons from the Earth and equalizes with the Earth." These electrons are thought to be used by the body to help improve function and reduce inflammation, leading to myriad health benefits.

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While Ober is credited as discovering earthing and bringing it to the masses through his work, he acknowledges the act of connecting to the ground in this way is not something he necessarily invented. Instead, he was inspired by his knowledge of electrical stability in the communications industry as a retired pioneer of the American cable TV industry and his childhood growing up near Native American communities.

He recalls one time being at the home of a Native American friend whose mom told them to take off their shoes.

"They'll make you sick," he recalls her saying, a concept that stuck with him as he later began thinking about the potential consequences of people no longer being naturally grounded to the Earth with the invention and use of rubber or synthetic soled shoes.

According to an article shared on the American Academy of Arts and Sciences website, Sicangu and Oglala Lakota author and educator Luther Standing Bear, writing in the 1930s, noted: "The old people came literally to love the soil and they sat or reclined on the ground with a feeling of being close to a mothering power. It was good for the skin to touch the earth and the old people liked to remove their moccasins and walk with bare feet on the sacred earth. ... The soil was soothing, strengthening, cleansing, and healing."

USA TODAY has reached out to Native women-led organization IllumiNative for comment.

What benefits can 'earthing' provide?

Once Ober started playing around with the idea of electrical charges in the home, body and ground, he started to note the "very apparent" effects he found, including improved sleep and reduced body pain.

Now 78, he says he stays grounded about 80% to 90% of the time with both outdoor grounding as well as tools he's helped develop that allow people to ground indoors through grounding rods and says he doesn't suffer from any inflammation-related health disorders.

There is plenty of research on the benefits nature can have on someone's mental health, but less on earthing specifically, especially in terms of physical health.

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In a study published in 2012, researchers found "emerging evidence shows that contact with the Earth – whether being outside barefoot or indoors connected to grounded conductive systems – may be a simple, natural and yet profoundly effective environmental strategy against chronic stress, ANS dysfunction, inflammation, pain, poor sleep, disturbed HRV, hypercoagulable blood, and many common health disorders, including cardiovascular disease."

Critics argue there are too few studies and not sufficient evidence to support these claims, pointing to a potential placebo effect that makes it difficult to validate from a scientific point of view.

"Unfortunately, we probably won't have the type of robust randomized-control trials on earthing that we would have for other medical and wellness interventions, but that doesn't mean there's no benefit," says Dr. Michael Daignault, an emergency room physician based in Los Angeles and USA TODAY medical columnist.

But for those like Sindicic who practice earthing, she tells skeptics to look at what the soil can provide for proof.

"Even vegetables are created in soil. Trees are created in soil, flowers, food, fruits ...  it's important to recognize the power of soil, the power of connecting to nature and Earth."

Sindicic says she's also experienced physical health benefits from grounding.

"Any of the electrons that come from Mother Earth are very healing, and it's a really beautiful experience," she says, adding she's seen a reduction in swelling in her feet and ankles while earthing.

The metaphysical and spiritual effects, she says, are "through the roof," explaining earthing was part of her own meditative emotional healing journey when she was younger.

Now, it's become embedded in her daily routine and helps with her mental health.

"When I wake up in the morning ... I'll go outside with my dogs and I will walk on the grass. That's how I begin my day," she says. "It may sound corny ... (but) that's a form of meditation to me. I can feel beneath my feet, the vibration of the earth and I feel very sound, I feel grounded. I feel like I can really start my day."

Daignault says any time spent in nature will "pay dividends on your mental and physical health."

"There's something inherently wellness-boosting about being outside."

Tips on giving 'earthing' a try:

If you're interested in exploring earthing, Sindicic suggests these simple steps:

• Take your socks off.

• Walk outside, even if it's just on some soil or grass in your backyard.

• Stand there for a moment and be quiet for three to 10 seconds.

• Take three deep breaths from your solar plexus chakra, which about 2 inches above your belly button.

"That's how you can begin this whole journey and how people try to figure out (their) place in this world," she says.

Sindicic also suggests earthing as a form of meditation or a launching pad for those who find it difficult to meditate.

Ober adds it's easy and free to give it a try, no matter who you are or how much time you have, though he suggests at least 30 minutes a day.

"Just walk outdoors, take your shoes off and put your bare feet on the ground. And if you're older and you have to sit, grab a chair and sit it in the backyard or even on the concrete patio," he says. "You will notice all of that tension in your body release."

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This article originally appeared on USA TODAY: Earthing, grounding has TikTok's attention. What you need to know.