Billions of people around the world live with chronic pain — and a staggering 40% of them also experience depression and anxiety.

"People usually assume that pain is a purely physical phenomenon," said Dr. Gary Small, a brain health expert and chair of psychiatry at Hackensack University Medical Center in New Jersey. "They focus on the part of the body affected. And certainly nerve cells, muscle tissue and joints are involved," said Small.

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"But you need a functioning brain to experience the sensation of pain. So, the brain and pain are very much linked," Small explained to Newsmax’s "National Report."

Chronic Pain and the Brain

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Chronic pain doesn’t just affect the body — it can also change the brain. "When pain becomes chronic, anybody who’s experienced that knows it’s debilitating," he said. "There are much higher rates of anxiety and depression with chronic pain. A condition called fibromyalgia, where you can’t locate a specific pain source, has even higher rates of depression and anxiety."

Even more striking: brain scans have shown that "with chronic pain, parts of the brain actually shrink — areas in the cortex, the outer rim of the brain," Small noted. "The good news is, with effective treatment of pain, that atrophy partially reverses."

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Therapies That Make a Difference

Psychological treatments can help reduce the physical sensation of pain. "Cognitive behavioral therapy helps people reframe their thinking about pain so they develop better coping strategies," explained Small, who is also the physician in chief for Behavioral Health Services at Hackensack Meridian Health. "Acceptance and commitment therapy increases mental flexibility so people can endure the pain rather than avoid it."

Antidepressants and anti-anxiety medications can help with the mental symptoms that often accompany pain, explained Small.

Do-It-Yourself Strategies

For those looking for self-help approaches, Small emphasized getting a proper medical evaluation first to rule out any underlying medical issues. But there are proven strategies people can use at home.

"Stress is something many people can handle themselves with meditation, breathing exercises, or other relaxation techniques that will help reduce that pain sensation," he said. "Exercise is very important. When we exercise, our body produces natural analgesics called endorphins, which also reduces inflammation, which can exacerbate that pain," said Small, editor of Dr. Gary Small’s Mind Health Report.

He also recommends a multi-pronged approach: "You can combine meditation with exercise. Sometimes acupuncture makes a difference as well as massage."

A Surprising Pain Reliever

Small also shared a surprising — and slightly humorous — finding. "When you swear, it actually reduces your pain," he said. Citing research from University of Oxford, he explained that "swearing led to a 33% increase in pain tolerance."