Is Inflammation Always Bad? Can We Use it to Heal?
Inflammation gets a bad rap. Consider the various anti-inflammatory diets, supplements, medications, and lifestyle tips aimed at providing some degree of relief from uncomfortable symptoms like redness, pain, heat, or swelling from an injury or infection.
“People definitely associate [inflammation] with something that’s negative,” says Wolfgang Marx, a senior research fellow and expert in nutritional psychiatry at Deakin University in Melbourne, Australia.
But the truth is far more complicated—and potentially beneficial. After centuries of debate and research, scientists now know that inflammation is as much a hero as it is an enemy. Ideally, the physiological process conquers infections, prevents cancer from taking hold, allows injuries to heal, turns vaccines into long-lasting disease protection, and more. In fact, we could not survive without the many roles that inflammation plays in the daily functioning of our bodies.
“Every facet of human health impinges on inflammation,” says Bali Pulendran, an immunologist at Stanford University. “Without the appropriate type and level of inflammation, the immune system would not be capable of launching effective immunity against pathogens.”
As with many biological reactions, though, the danger lies in how much. When inflammation persists at chronically elevated levels after an initial infection or injury has passed, it can shift functions, leading to long-term illnesses such as heart disease, cancer, type 2 diabetes, depression, and Alzheimer’s. Many of these conditions become more common with aging, which is also linked to rising levels of inflammation. The immune system is capable of attacking the body’s own tissues, resulting in autoimmune conditions such as rheumatoid arthritis, multiple sclerosis, and Crohn’s disease. Some researchers are also exploring whether there’s a connection between excessive inflammation and long COVID.
Over the past two decades, such major yet often contradictory health impacts have galvanized scientists to dig deeper into understanding this process. When geriatrician and epidemiologist Luigi Ferrucci started looking into the links between inflammation and aging in 1999, there were five or six known molecules, called markers or mediators, that were used as measures of inflammation in the body. Today there are thousands.
