Understanding Chronic Inflammation: Recognizing Its Prevalence and Identifying Symptoms

Inflammation is a natural part of the body’s healing process—but when that inflammation lingers, people are at risk for a cascade of health concerns. So, how can you figure out if you have it?

Whether it presents as a red, swollen, stubbed toe or a runny, stuffed-up nose, inflammation is something everyone experiences. Simply, it’s your immune system responding in real time to defend against infections, the presence of toxins or foreign objects, or other health threats.

However, sometimes, this inflammation can persist for months or even years at a time. Chronic inflammation is a marker of many health conditions, from rheumatoid arthritis to ulcerative colitis (UC), and has recently been linked to cognitive and brain health concerns.

A study published in Neurology in July found having elevated levels of inflammation in one’s 20s and 30s could be associated with issues with memory and thinking later in life. Specifically, the study participants who had higher levels of C-reactive protein (CRP)—an inflammation marker generated by the liver—had more cognitive issues in midlife.

Plus, a JAMA Psychiatry study from August showed that children with chronic inflammation were found to be at higher risk of mental health conditions such as depression and psychosis by early adulthood.

Given how dangerous and common systemic inflammation is—one study revealed nearly 35% of U.S. adults have it—people might find it surprising that doctors don’t typically administer inflammation tests at annual physicals. Too often, inflammation can remain unchecked and under-treated.

Here’s what experts had to say about inflammation’s impact on the body, why detecting inflammation can be a challenge, and what you can do if you think you might be experiencing chronic inflammation.

In many ways, inflammation’s impact on the body—especially when it comes to memory or mental health issues—is something researchers are “still learning about, honestly,” said Thad Stappenbeck, MD, PhD, the chair of Inflammation and Immunity at Cleveland Clinic.

But based on the research that has been conducted so far, Stappenbeck told Health that it seems “pretty clear” that having inflammation early in life will go on to directly impact your health as you age.

When a person is experiencing inflammation, the cells responsible for the immune response (such as white blood cells) invade tissue and produce inflammatory proteins and other enzymes. This is a “beneficial response” in the short-term and can help protect against harmful microorganisms or other problems, said Helen Lavretsky, MD, a professor-in-residence in the Department of Psychiatry at UCLA. This acute inflammation usually brings redness, heat, swelling, and pain, she added.

However, a prolonged immune response can actually damage the tissue, leading to a host of health issues.

“Inflammatory processes accelerate brain aging, causing gray and white matter atrophy and vascular changes that can result in reduced cognitive function and impaired emotion regulation,” Lavertsky told Health. “Inflammation is linked to various neuropsychiatric disorders like depression, anxiety, insomnia, autism spectrum disorders, dementia, stroke, and many other brain disorders.”

Lavretsky said inflammation is also associated with a wide range of physical disorders—these include arthritis, diabetes, gut disorders, chronic pain disorders, and kidney issues, among many more.

In fact, research has shown that higher levels of the inflammation marker CRP are associated with a higher risk of coronary heart disease and death from cardiovascular disease. And three in five people globally die of diseases linked to chronic inflammation, including obesity, diabetes, cancer, and heart disease.

There are a number of things that can trigger problematic inflammation, Jennifer Frankovich, MD, clinical professor in the Division of Allergy, Immunology, and Rheumatology at Stanford University/Lucile Packard Children’s Hospital, told Health.

Inflammation can start from an infection or some kind of physical injury, said Lavertsky. Environmental exposures to chemicals can also trigger inflammation, as can psychological trauma, she said.

But for some people, this inflammation doesn’t go away. This could be because they have a dysregulated or heightened immune system, Frankovich said, which can stem from in-utero exposures or infections early in life.

Others might be predisposed to immune system imbalances or have some genetic predispositions that make it harder to fight off infections. On the flip side, some people might have immune systems that are “too robust,” said Frankovich, which can also lead to chronic inflammation.

Diet can also play a role in the development of chronic inflammation, particularly for people who have gut health issues, she added.

Despite the wide-ranging consequences associated with inflammation, researchers are still learning more about how to diagnose and address it.

Most of the guidepost research on inflammation has been conducted in animals, so additional research in humans is needed to better understand the mechanisms behind inflammation, as well as pave the way for improved preventive measures, Frankovich said.

“We have a whole armory of sorts of medications that can be used to calm inflammation,” said Frankovich. “If we can identify who is at risk for these awful conditions like schizophrenia, depression, psychosis, if we know that early inflammation predisposes people to this, then we can figure out who is really at risk [and] we can prevent it. It’s a beautiful thing.”

This is something Frankovich does currently in her work at the Immune Behavioral Health Clinic at Stanford, where she helps determine if treating kids for inflammation could ease their psychiatric conditions.

However, this dual approach of addressing both a certain health issue and the underlying inflammation is unique to her clinic. For that approach to be the norm, Frankovich said the medical system itself would have to evolve.

On the patient side, there’s also a need for a better understanding of what inflammation looks like and how it works.

One issue with diagnosing inflammation is that many people “are very stoic” when it comes to explaining changes in their health, Frankovich said. Plus, since chronic inflammation can persist for years, it can seem normal for patients—the condition can be “insidious; [people] don’t realize they have it,” she explained.

Signs of inflammation also tend to be subtle—they include morning sickness, stiffness or pain in the back, pain in the knees, ankles, elbows, or bottom of the feet, or joints feeling like they’re “getting stuck” after sitting still for a while, Frankovich said. People might also experience redness of the skin, difficulty breathing or moving, swelling (edema), or the loss of smell, added Lavertsky.

Inflammation testing likely won’t be a routine part of your annual checkup, experts said. That being said, people may want to ask their healthcare provider about testing, particularly if they’re experiencing any symptoms of inflammation.

“As a medical field, we need to do a better job of screening for these inflammatory conditions so we can diagnose them early and treat them early,” said Frankovich.

Blood testing is the simplest to assess if someone has an inflammatory condition, Lavertsky explained. These are the four most common tests, she said:

Outside of blood tests, ultrasounds or other imaging can also be performed to look for inflammation, Frankovich said.

Treating inflammation can be similarly complex—there isn’t a one-size-fits-all approach since the conditions manifests itself so differently from person to person, said Lavertsky.

Medications are one option, but healthcare professionals might also recommend lifestyle changes to reduce inflammation, including losing excess weight, reducing stress, and getting enough sleep, Lavertsky explained. Beyond this, sticking to an anti-inflammatory diet high in green leafy vegetables, grapes, and omega-3 oils can be helpful. That also means reducing consumption of added sugars, red meat, and fried foods, which can be inflammatory, she said.