Published 9th June 2026
Inflammation explained: How to manage your levels
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If you've typed "what is inflammation" into a search bar, you've probably heard the word thrown around a lot. It's often brought up in the context of chronic disease, gut health, aging, and the foods you eat.
But the term covers a lot of ground, and the science is more specific (and more interesting) than most wellness content lets on.
Inflammation is your immune system doing its job. The short-term version is essential to survival.
On the other hand, long-term, low-grade versions, the ones you often can't feel, are one of the drivers of some of the most serious conditions we face.
Understanding the difference matters because how you manage it is different, too.
This article explains what inflammation is, how acute and chronic types differ, which conditions it's linked to, what causes it to persist, and what the evidence says you can actually do about it.
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What is inflammation?
Inflammation is the body's immediate response to tissue injury, infection, or any signal that something is wrong.
When your immune system detects a threat (whether that's bacteria, a damaged cell, or a foreign substance), it triggers a cascade of events designed to contain the threat and start repair.
You've seen this in action. A sprained ankle swells. A paper cut turns red and warm. A throat infection makes swallowing painful. These are the classic signs: redness, heat, swelling, pain, and sometimes loss of function.
They have Latin names that date back to ancient Rome (rubor, calor, tumor, dolor, functio laesa), and they're still how we teach the basics today.
Behind the scenes, blood vessels dilate and become more permeable, allowing immune cells (mainly neutrophils in the first wave) to flood the site.
Signaling proteins called cytokines (including IL-1, IL-6, and TNF-alpha) coordinate the response, calling in more cells, amplifying the attack when needed, and then, crucially, winding it down when the threat has passed.
Inflammation is meant to resolve. There are specialized molecules called pro-resolving mediators (including resolvins and protectins) that actively shut the response down and restore normal tissue function.
This resolution isn't passive; it's a tightly regulated biological program. When it works properly, you heal.
Acute vs chronic inflammation
The distinction between acute and chronic inflammation is important because they’re fundamentally different processes. They have different causes, different symptoms, and different consequences.
Acute inflammation is fast and purposeful. It kicks in within minutes to hours, peaks, and in most cases resolves within days.
Bacterial pneumonia, a wound infection, appendicitis, and a gout flare all involve acute inflammation.
The symptoms tend to announce themselves: pain, visible swelling, and fever. Neutrophils are the dominant players.
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Chronic inflammation is slower and often silent. It develops when the acute response fails to resolve (because the triggering stimulus persists or the resolution mechanisms aren't functioning properly).
Alternatively, it can develop gradually on its own, without a clear trigger event.
The symptoms are less dramatic and can include fatigue, low-grade fever, and unexplained weight loss over time. The cells involved shift from neutrophils to macrophages and lymphocytes.
The tissue changes are progressive, causing ongoing damage, fibrosis, and scarring.
What makes chronic inflammation particularly concerning is that it can cause significant organ damage long before any symptoms are obvious.
Atherosclerosis, for instance, involves decades of quiet vascular inflammation before it shows up as a heart attack. Similarly, chronic hepatitis can silently progress to cirrhosis.
Inflammation and chronic conditions
Inflammation plays a role in a surprising number of serious health conditions:
Cardiovascular disease
The 2025 ACC Scientific Statement on Inflammation and Cardiovascular Disease is unusually direct.
The authors explain that the link between inflammation and heart disease is "no longer exploratory but compelling and clinically actionable."
Inflammatory proteins damage the lining of blood vessels, drive the build-up of plaques, and can trigger those plaques to rupture, causing heart attacks and strokes.
Elevated CRP levels (a marker of inflammation) predict future cardiovascular events, even in people already taking statins.
The CANTOS trial — a large study that specifically targeted an inflammatory protein called IL-1 beta — reduced major cardiovascular events without affecting cholesterol levels.
This is significant because it confirms that inflammation is a cause, not just a symptom.
Type 2 diabetes
A 2001 JAMA study found that elevated CRP and IL-6 predicted the development of type 2 diabetes years before it was diagnosed.
This relationship is partly driven by visceral fat (the fat stored around your organs), which releases inflammatory signals that interfere with how your body responds to insulin.
Once diabetes develops, it further amplifies inflammation, creating a cycle that's hard to break.
Cancer
Chronic inflammation creates conditions that make it easier for abnormal cells to survive, grow, and spread.
The same CANTOS trial that targeted inflammation for heart disease incidentally found a reduction in lung cancer incidence, providing direct evidence that lowering inflammation can reduce cancer risk.
Neurodegeneration
The brain has its own immune cells, called microglia. When these are chronically activated, they can damage neurons rather than protect them.
This is increasingly recognized as a factor in Alzheimer's disease, Parkinson's disease, and multiple sclerosis (MS).
Researchers use the term "inflammaging" to describe how this low-grade brain inflammation accumulates with age, contributing to cognitive decline.
Autoimmune conditions
In rheumatoid arthritis, inflammatory bowel disease (IBD), lupus, and psoriasis, the immune system mistakenly attacks healthy tissues.
These conditions also raise the risk of heart disease, partly because sustained systemic inflammation accelerates blood vessel damage over time.
What connects all of these conditions is that the same inflammatory pathways are active across very different diseases.
This is why researchers increasingly treat cardiovascular disease, diabetes, cancer, and neurodegeneration not as separate problems, but as conditions that share a common root.
What causes inflammation?
The immune system triggers inflammation when it detects two types of danger signals, as described in a 2025 paper in Immunological Reviews.
The first are molecules from invading pathogens — bacteria, viruses, fungi — that the body recognizes as foreign.
The second comes from your own cells when they're injured, stressed, or dying; these trigger what's called "sterile inflammation." This is an immune response with no infection involved.
Either way, once the alarm is sounded, immune cells are recruited and inflammatory proteins are released to deal with the threat.
Common causes of acute inflammation:
Infections: Bacterial, viral, fungal, parasitic.
Physical trauma, burns, or frostbite.
Chemical injury or toxin exposure.
When tissue is starved of oxygen, and then blood rapidly returns (as occurs in a heart attack or stroke).
Foreign bodies: Splinters, inhaled particles, implanted devices.
Crystal deposition: Uric acid crystals (as in gout) can directly trigger an inflammatory response.
For chronic inflammation, the picture is more complex. Persistent infections (hepatitis B or C, tuberculosis, HIV) maintain ongoing immune stimulation.
Autoimmune dysregulation also sustains inflammatory attacks on healthy tissue. But many of the causes are modifiable:
Obesity. Fat stored around the organs (visceral fat) actively releases inflammatory signals. Immune cells accumulate in this fat tissue, driving a chronic inflammatory state that impairs the body's response to insulin.
Poor diet. Western diets high in refined carbohydrates, saturated fats, and ultra-processed foods consistently promote inflammation. Mediterranean-style diets do the opposite.
Physical inactivity. Sedentary behavior is independently associated with elevated systemic inflammatory markers, independent of weight.
Smoking. This is a major driver of inflammation, both through direct tissue irritation and by impairing healing. Smoking reduces the body's production of resolvins, making it harder to switch off inflammatory responses.
Psychological stress. Chronic stress activates the body's stress-response systems (including the hormonal and nervous system pathways involved in the fight-or-flight response), which sustains elevated inflammatory signals over time.
Aging ("inflammaging"). As we get older, cells accumulate damage, energy production in cells becomes less efficient, and the gut microbiome shifts in ways that all nudge the immune system toward persistent activation.
Gut dysbiosis. Disrupted gut microbiome composition and increased intestinal permeability allow microbial products to enter the bloodstream, driving systemic low-grade inflammation. Eating more fermented foods is one of the most practical ways to support gut barrier health and microbial diversity.
Environmental exposures. Air pollution, pesticides, and heavy metals cause chronic tissue irritation and oxidative stress.
These factors rarely act in isolation. They interact and amplify each other, and combined, they represent the upstream, modifiable determinants of much of the chronic disease burden we see today.
Can food help reduce inflammation?
Yes, and this is one of the areas with the strongest and most clinically relevant evidence in nutrition science.
The Mediterranean diet has the most consistent data. A 2025 meta-analysis of randomized controlled trials found it produced significant reductions in multiple inflammatory markers compared with control diets.
The PREDIMED trial, one of the largest dietary RCTs conducted, showed that Mediterranean diets supplemented with extra-virgin olive oil or nuts produced sustained reductions of at least 16% in key inflammatory markers at both 3 and 5 years.
A low-fat control diet showed no significant change over the same period.
A 2026 review of 30 systematic reviews covering 225 studies confirmed that the Mediterranean and vegetarian dietary patterns have strong evidence for reducing low-grade inflammation, with the Mediterranean diet showing the strongest.
The foods that do the most work
Omega-3 fatty acids. Found in fatty fish (salmon, mackerel, sardines), algae oil, flaxseeds, and chia seeds.
They dampen inflammatory signaling, and the body uses them to produce the molecules that actively switch inflammation off. The 2025 American College of Cardiology (ACC) Statement recommends two to three fish meals per week, prioritizing fatty fish high in EPA and DHA.
Polyphenols and flavonoids. Found in berries, grapes, green tea, extra-virgin olive oil, turmeric (curcumin), dark chocolate, and colorful vegetables.
These compounds block key inflammatory triggers in the body. Clinical trials have confirmed the anti-inflammatory effects of cranberries, pomegranate, strawberries, and green tea specifically.
Dietary fiber, particularly cereal fiber. Whole grains and oats are fermented by gut bacteria into short-chain fatty acids (SCFAs), including butyrate, which strengthens the gut barrier and suppresses inflammation.
A 2022 study in JAMA Network Open in older adults found that cereal fiber was the primary driver of anti-inflammatory effects across all fiber sources.
Vegetable and fruit fiber showed weaker or no associations, a nuance worth knowing if you're relying on fruit and veg for your fiber. There's also a growing body of evidence connecting fiber intake to reduced risk of heart disease.
Other lifestyle interventions
Aside from diet, many other lifestyle factors can really make a difference to your inflammation levels.
Exercise
Long-term exercise training significantly reduces circulating inflammatory markers, with the greatest effects observed at moderate-intensity training sustained for more than 12 weeks.
This is partly because muscles release anti-inflammatory signals as they work, which helps protect blood vessels and support repair.
Worth noting: Research suggests that higher exercise intensity may reduce inflammation to a lesser extent, suggesting moderate intensity may be optimal if reducing inflammation is the specific goal.
The ACC recommends a minimum of 150 minutes of moderate aerobic exercise or 75 minutes of vigorous exercise per week.
For a closer look at how movement targets inflammaging, this ZOE Science & Nutrition episode with Prof. Janet Lord is worth your time.
Quitting smoking
Smoking is one of the most significant modifiable drivers of systemic inflammation.
In the Multi-Ethnic Study of Atherosclerosis, current smokers had significantly higher levels of inflammatory markers than never-smokers, with a clear dose-response: The more someone had smoked over their lifetime, the higher their inflammation.
Every 5 years of not smoking reduced the odds of elevated CRP by 9%. Even 14 days of stopping smoking significantly reduced inflammatory markers toward non-smoker levels.
CRP reductions take longer; one prospective study found the effect on CRP became significant only after 4 or more years of sustained abstinence. But the direction is clear from day 1.
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Alcohol
On inflammatory markers specifically, the Whitehall II study, which included data from 8,209 participants, found that stable moderate drinkers had lower CRP than both non-drinkers and heavy drinkers over 12 years.
Also, stable heavy drinkers had both higher IL-6 and faster rates of IL-6 increase over time. That J-shaped pattern is real in the data. But CRP is not the full picture.
The WHO's current position is that no level of alcohol consumption is safe, and the broader evidence on cancer risk and brain volume loss doesn't support treating any CRP benefit from light drinking as meaningful.
Heavy drinking clearly worsens systemic inflammation; light drinking's effect on inflammation is a minor, contested finding against a much larger risk backdrop. It's not a lever worth pulling.
Weight management
Fat stored around the organs is metabolically active and releases inflammatory signals. Losing it reduces both local and systemic inflammation.
The ACC identifies weight management alongside exercise and smoking cessation as the three primary lifestyle levers for reducing inflammatory burden, and their effects compound when combined.
Summary
Inflammation is not inherently a problem. In its acute form, it's how the body protects itself and heals. The issue is when it becomes chronic, driven by persistent infections, autoimmune dysregulation, or the slower, more modifiable forces of lifestyle.
Chronic low-grade inflammation operates quietly, over years. It drives cardiovascular disease, type 2 diabetes, cancer, and neurodegeneration not as a bystander, but as a direct mechanism.
The shared inflammatory pathways across these conditions mean that what reduces inflammation broadly tends to lower risk across multiple disease categories at once.
The evidence is clear for diet (particularly Mediterranean-pattern eating and cereal fiber), regular moderate exercise, quitting smoking, and maintaining a healthy weight.
These aren't vague lifestyle suggestions; they reduce measurable inflammatory biomarkers in randomized trials. Combined, their effects are substantially larger than any single change in isolation.
FAQs
Here are the answers to some commonly asked questions:
What is inflammation in simple terms?
Inflammation is your immune system's response to injury, infection, or other forms of damage.
It's the redness, swelling, heat, and pain you see around a wound or infection. Short-term, it's how you heal. Long-term and low-grade, it's linked to serious disease.
Is inflammation always bad?
No. Acute inflammation is essential; without it, even minor infections could become life-threatening. It becomes a problem when it doesn't resolve and becomes chronic, quietly damaging tissues over months or years.
What are the signs of chronic inflammation?
Chronic inflammation often has no obvious symptoms. When it does, they tend to be non-specific: persistent fatigue, low-grade fever, unexplained weight loss. The most reliable way to detect it is through blood tests that measure markers of systemic inflammation, like high-sensitivity CRP.
What foods cause inflammation?
Ultra-processed foods, sugar-sweetened drinks, refined carbohydrates, and diets high in processed red meat are consistently associated with higher inflammatory markers. The overall dietary pattern matters more than any single food.
What foods help reduce inflammation?
The Mediterranean diet has the strongest evidence, with fatty fish (omega-3s), polyphenol-rich foods (berries, olive oil, green tea), and cereal fiber (whole grains, oats) being the key components.
Can you completely eliminate chronic inflammation?
Not always, but you can reduce it substantially. For most people with lifestyle-driven chronic inflammation, a combination of dietary changes, regular exercise, not smoking, and maintaining a healthy weight can meaningfully lower inflammatory burden.
What is the difference between acute and chronic inflammation?
Acute inflammation is fast, obvious, and short-lived; it's what happens when you get an infection or injure yourself. Chronic inflammation is slow, often invisible, and can persist for months or years without obvious symptoms.
