If it feels like everyone is suddenly talking about inflammation, you’re not imagining it. The term pops up everywhere from wellness podcasts and social media to grocery store packaging promoting “anti-inflammatory” ingredients.
Despite all the buzz, many people still aren’t sure what inflammation actually is – or whether it’s something they should be worried about.
While the answer is more nuanced than many headlines suggest, understanding what inflammation is – and the role your diet plays – can help you make more informed choices without falling for the hype.
What is inflammation?
While it gets a bad rap, inflammation is actually “the body’s natural immune response to injury, infection or toxins, aimed at protecting and healing tissue,” says Caroline Susie, a registered dietitian and national spokesperson for the Academy of Nutrition and Dietetics.
When you cut your finger, catch a virus or sprain an ankle, inflammation is the short-term response your body uses to fight infection, remove damaged cells and begin the healing process. In this way, inflammation is beneficial and normally resolves once the threat has passed.
But problems arise when inflammation becomes chronic, meaning it persists even when there is no injury or infection to fight, or “when the response persists too long and starts attacking healthy tissues,” says Susie.
Chronic inflammation, she explains, has been linked to conditions such as heart disease, type 2 diabetes, arthritis, certain cancers and Alzheimer’s disease. “In addition to physical diseases, chronic inflammation is implicated in the development of mental illness, including depression,” adds Susie.
People with chronic inflammation may also experience symptoms such as persistent fatigue, joint pain or stiffness and digestive problems.
Left unchecked, chronic inflammation can gradually damage healthy tissues and organs, increasing the risk of long-term disease and reduced physical function.
What are the most common causes of inflammation?
Although diet receives much of the attention, it’s only one of many factors that can contribute to inflammation.
“Other common causes of inflammation include infection, chronic disease, excess body fat, stress, poor sleep and inactivity,” says Amy Goodson, a nutritionist and registered dietitian at the Sports Nutrition Playbook.
She explains that infections caused by bacteria, viruses, fungi or parasites naturally trigger inflammation as the immune system works to eliminate harmful invaders. Excess body fat, particularly around the abdomen, also produces inflammatory chemicals that can keep the immune system activated over time. Chronic stress contributes by “increasing hormones that influence immune function,” Goodson explains, while inadequate sleep disrupts the body’s normal regulation of inflammation.
“And medical conditions such as autoimmune diseases like rheumatoid arthritis and lupus, plus obesity, type 2 diabetes and metabolic syndrome all involve and perpetuate chronic inflammatory states,” adds Susie. This is largely because they cause ongoing immune-system activation and metabolic dysfunction that continually signals the body to produce inflammatory compounds.
She adds that smoking, excessive alcohol consumption and exposure to environmental pollutants have likewise been associated with higher levels of chronic inflammation because they increase oxidative stress, damage cells and continually stimulate the body’s immune response.
How to reduce inflammation
Beyond these other causes, “diet also plays a major role,” notes Goodson, “as what you eat can either fuel inflammation or help calm it, depending on nutrient quality and overall eating patterns.”
Foods that increase inflammation, or make existing inflammation worse, include highly processed foods, added sugars and fried foods, which can all “trigger inflammatory pathways and cause oxidative stress,” she explains.
Partially hydrogenated oils, also known as trans fats, can also contribute. “Although largely phased out in the U.S., they still appear in some imported or shelf-stable products,” cautions Susie. “If you see ‘partially hydrogenated’ anywhere in a foods’ ingredient list, avoid it.”
Processed meats such as bacon, sausage, hot dogs and deli meats may also contribute to inflammation because they’re high in sodium, preservatives and compounds formed during processing that have been linked to increased inflammatory activity. They can also contribute to weight gain, which further promotes chronic inflammation.
Susie also recommends limiting refined grains because they digest quickly, can cause repeated spikes in blood sugar and insulin levels and are lower in the fiber that helps support a healthy gut microbiome. “If it just says ‘enriched wheat flour,’ ‘bleached flour’ or simply ‘wheat flour,’ it’s refined,” she explains.
On the other hand, “fruits, vegetables, whole grains, nuts, seeds, olive oil and spices like turmeric provide antioxidants and omega-3s that help lower inflammation,” says Goodson. These foods also help neutralize damaging free radicals, support a healthier gut microbiome and provide nutrients that help regulate the body’s inflammatory response.
For the same reasons, Susie recommends eating fatty fish such as salmon, sardines and mackerel; legumes such as beans, lentils and chickpeas; and healthy fats from foods like olive oil and avocados.
Rather than trying to eliminate individual foods entirely or focusing on a handful of “superfoods,” Goodson says it’s better to build an overall eating pattern centered on “more products with whole-food ingredients.”
Whole dietary patterns can make this easier. For example, Susie points to a meta-analysis of 22 randomized controlled trials that found a Mediterranean-style diet was the most effective dietary pattern for reducing inflammation, producing significant reductions in several major inflammatory markers.
Ultimately, no single food causes – or cures – chronic inflammation on its own, but over time, Goodson says, “consistently choosing a diet rich in minimally processed, nutrient-dense foods while maintaining healthy habits like regular exercise, quality sleep and stress management can go a long way toward keeping inflammation in check and supporting long-term health.”