Anti-Inflammatory Foods: What the Evidence Actually Shows

Chronic low-grade inflammation is implicated in nearly every non-communicable disease of modern life: cardiovascular disease, type 2 diabetes, Alzheimer's, autoimmune conditions, and several cancers. The dietary pattern that drives this inflammation is the Western diet, high in refined carbohydrate, added sugar, ultra-processed foods, and industrial seed oils, and low in fiber, omega-3 fatty acids, and polyphenols. The dietary pattern that suppresses it is the Mediterranean diet, and more specifically a pattern built around oily fish, vegetables, fruit, legumes, whole grains, nuts, olive oil, and spices. This guide covers what inflammation actually is, the Dietary Inflammatory Index, the foods with the strongest evidence for reducing inflammatory markers, and how to build an anti-inflammatory plate.

What is inflammation? Acute vs chronic

Inflammation is the immune system's response to injury or infection. Acute inflammation is useful and self-limiting: you cut your finger, the area gets red and warm as immune cells rush to fight pathogens and repair tissue, and the inflammation resolves as healing completes. The classic signs of acute inflammation are heat, redness, swelling, pain, and loss of function.

Chronic low-grade inflammation is different. It is a persistent, low-level activation of the immune system that does not resolve. It is measurable through blood markers like C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-alpha). These markers are elevated in people with obesity, metabolic syndrome, type 2 diabetes, cardiovascular disease, and autoimmune conditions. Chronic inflammation damages tissue over time: it oxidizes LDL cholesterol (driving atherosclerosis), impairs insulin signaling (driving diabetes), and damages neurons (driving cognitive decline).

Diet is one of the strongest modifiable drivers of chronic inflammation. A 2021 review in Nature Medicine estimated that diet accounts for 30 to 40 percent of the variation in inflammatory markers between individuals, comparable to the effect of obesity itself. The mechanism is twofold: pro-inflammatory foods directly raise inflammatory markers, and anti-inflammatory foods directly lower them. The net inflammatory load of a diet is the balance between the two.

The Dietary Inflammatory Index

The Dietary Inflammatory Index (DII) was developed by Shivappa and colleagues at the University of South Carolina in 2014, published in Public Health Nutrition. It scores diets on a scale from about -8 (most anti-inflammatory) to +8 (most pro-inflammatory), based on the intake of 45 food parameters including macronutrients, micronutrients, flavonoids, and specific bioactive compounds. The DII has been validated against CRP, IL-6, and TNF-alpha in multiple cohorts.

Population studies using the DII have shown that people with the most pro-inflammatory diets (highest DII scores) have higher rates of cardiovascular disease, type 2 diabetes, several cancers, depression, and all-cause mortality compared to people with the most anti-inflammatory diets. A 2020 meta-analysis in Advances in Nutrition pooled 31 cohort studies and found that the highest versus lowest DII category was associated with a 36 percent higher risk of all-cause mortality, a 44 percent higher risk of cardiovascular mortality, and a 23 percent higher risk of cancer mortality.

The DII is a research tool, not a calculator most people will use day to day. The practical takeaway is that the same foods that score anti-inflammatory on the DII are the foods that have decades of evidence for reducing chronic disease: vegetables, fruits, whole grains, legumes, nuts, olive oil, and oily fish. Score your overall diet pattern with our Mediterranean Diet Score Calculator, which captures most of the same foods.

Foods that fight inflammation

Omega-3 fatty acids (EPA and DHA)

Omega-3 fatty acids are the most studied anti-inflammatory nutrient. EPA and DHA, the long-chain omega-3s found in oily fish, are precursors to resolvins and protectins, lipid mediators that actively resolve inflammation. A 2019 meta-analysis in the Journal of the American College of Cardiology pooled 17 trials and found that omega-3 supplementation at 1 to 4 g/day of EPA plus DHA reduced CRP by about 25 percent and reduced cardiovascular events in high-risk populations.

The best food sources of EPA and DHA are salmon, sardines, mackerel, herring, anchovies, and trout. Aim for 2 to 3 servings per week. Plant sources of omega-3 (flaxseed, chia, walnuts) provide ALA, which is converted to EPA and DHA at a low rate (under 5 percent for EPA and under 0.5 percent for DHA), so they are less efficient but still useful. Use our Omega-3 Calculator to check your intake.

Polyphenol-rich foods

Polyphenols are plant compounds with antioxidant and anti-inflammatory effects. They are responsible for the color, flavor, and many of the health benefits of plant foods. The major classes are flavonoids (in berries, citrus, tea, cocoa), phenolic acids (in coffee, whole grains), and stilbenes (in red wine, berries). A 2021 umbrella review in Advances in Nutrition found consistent evidence that high polyphenol intake is associated with lower CRP, lower IL-6, and reduced risk of cardiovascular disease, type 2 diabetes, and cognitive decline.

The best food sources are berries (especially blueberries, blackberries, and raspberries), dark chocolate (over 70 percent cocoa), tea (green and black), coffee, extra-virgin olive oil, and colorful vegetables. Herbs and spices are concentrated sources: turmeric (curcumin), ginger, cinnamon, cloves, and oregano are all exceptionally high in polyphenols. Aim for a variety of colors on your plate, because different polyphenols have different but complementary effects.

Fiber and whole foods

Dietary fiber is anti-inflammatory through a less obvious mechanism: the gut microbiome. Fiber that reaches the colon is fermented by bacteria into short-chain fatty acids (SCFAs), primarily butyrate, propionate, and acetate. SCFAs are anti-inflammatory: they reduce gut permeability, regulate immune cell function, and lower systemic CRP. A 2020 study in Gut found that increasing fiber intake from 15 to 30 g per day for 10 weeks increased SCFA production, reduced markers of gut inflammation, and lowered systemic CRP by 12 percent.

The best sources are legumes (lentils, chickpeas, beans), whole grains (oats, barley, quinoa), vegetables, fruit, nuts, and seeds. Aim for 25 to 35 g per day. Use our Fiber Calculator to set your target. The fiber should come from whole foods, not from supplements or fortified processed foods, because whole foods provide the matrix of fiber, polyphenols, and micronutrients that drive the benefit.

Extra-virgin olive oil

Extra-virgin olive oil is the centerpiece of the Mediterranean diet and one of the most studied anti-inflammatory foods. It is rich in oleic acid (a monounsaturated fat) and in polyphenols, especially oleocanthal, which has a similar anti-inflammatory mechanism to ibuprofen. A 2022 trial in Nutrients found that adding 50 mL per day of high-polyphenol extra-virgin olive oil to the diet for 3 weeks reduced CRP by 18 percent and IL-6 by 15 percent. The benefit is specific to extra-virgin (which contains the polyphenols); regular olive oil is refined and has lost most of them.

Nuts

Nuts are anti-inflammatory through their combination of unsaturated fats, fiber, polyphenols, and magnesium. A 2018 meta-analysis in The American Journal of Clinical Nutrition pooled 21 trials and found that adding 1 to 2 oz of nuts per day reduced CRP by about 20 percent. Walnuts have the most evidence, probably because they are the only nut with substantial omega-3 ALA. Almonds, pistachios, and hazelnuts are also well-studied. Avoid nuts roasted in unhealthy oils or coated in sugar and salt.

Cruciferous vegetables

Broccoli, Brussels sprouts, cabbage, kale, and cauliflower contain glucosinolates, which are converted in the body to sulforaphane and other compounds with anti-inflammatory and anti-cancer effects. A 2019 meta-analysis in the British Journal of Nutrition found that high cruciferous vegetable intake was associated with a 12 percent lower CRP and a 17 percent lower risk of cardiovascular disease. Aim for 3 to 5 servings per week; cooking them lightly (steaming, sauteing) preserves more glucosinolates than boiling.

Foods that promote inflammation

The pro-inflammatory foods are essentially the Western diet. A 2019 study in Nutrients estimated that 58 percent of the calories consumed by American adults come from ultra-processed foods, which are the primary driver of dietary inflammation.

• Refined carbohydrates and added sugars: White bread, white rice, sweetened beverages, pastries, and breakfast cereals raise blood glucose and insulin rapidly, which promotes inflammation via advanced glycation end products (AGEs) and oxidative stress. Use the Glycemic Load Calculator and Sugar Calculator to assess your intake.
• Fried foods and industrially processed oils: Deep-fried foods, margarine, and foods made with partially hydrogenated oils contain trans fats (mostly banned now) and oxidized fats that drive inflammation. Some seed oils (sunflower, safflower, soybean) are high in omega-6 linoleic acid, which is pro-inflammatory in excess, though the evidence is mixed and the omega-6 to omega-3 ratio hypothesis is contested.
• Red and processed meat: Processed meats (sausages, bacon, hot dogs, deli meats) are classified by the World Health Organization as Group 1 carcinogens. They contain nitrates, heme iron, and AGEs that promote inflammation and colorectal cancer. Unprocessed red meat in moderation is less problematic but still associated with higher CRP in observational studies.
• Ultra-processed foods: The category of foods made mostly from extracted ingredients (flours, sugars, oils) with additives and minimal whole-food content. A 2019 controlled trial by Hall and colleagues in Cell Metabolism found that people ate 500 more calories per day on an ultra-processed diet than on a whole-food diet matched for macronutrients, and gained weight rapidly.
• Excess alcohol: Heavy drinking is potently pro-inflammatory. The relationship is J-shaped for light drinking in some studies (apparent benefit at 1 drink per day), but more recent Mendelian randomization studies suggest this is confounding, not a true benefit.

The Mediterranean diet and inflammation

The Mediterranean diet is the most studied anti-inflammatory dietary pattern. The PREDIMED trial, which randomized 7,447 Spaniards at high cardiovascular risk to a Mediterranean diet supplemented with olive oil or nuts versus a low-fat control, found that the Mediterranean diet groups had lower CRP, lower IL-6, and lower adhesion molecules (markers of vascular inflammation) at 5 years. The effect size was clinically meaningful: about a 30 percent reduction in major cardiovascular events.

The anti-inflammatory effect of the Mediterranean diet appears to come from the combination of its components rather than any single food. The diet is high in omega-3 (from fish and walnuts), high in polyphenols (from olive oil, berries, vegetables, wine), high in fiber (from legumes, whole grains, vegetables), low in refined carbohydrate and added sugar, and low in ultra-processed food. Score yourself with the Mediterranean Diet Score Calculator.

Specific conditions

Rheumatoid arthritis

Rheumatoid arthritis is an autoimmune disease with prominent inflammation. A 2023 meta-analysis in Frontiers in Nutrition pooled 14 trials and found that Mediterranean diet interventions reduced joint pain and morning stiffness by about 20 to 30 percent, with corresponding reductions in CRP. Omega-3 supplementation at 2 to 4 g/day of EPA plus DHA has consistent evidence for reducing joint tenderness. The benefit is modest but real, and the diet has no side effects.

Cardiovascular disease

Inflammation drives atherosclerosis. The CANTOS trial (2017) showed that reducing inflammation with a monoclonal antibody (canakinumab) reduced cardiovascular events independently of LDL cholesterol, confirming that inflammation is a causal driver, not just a marker. Diet affects the same pathway: the Mediterranean diet reduces CRP by about 20 to 30 percent in trials, which is roughly the magnitude needed to explain much of its cardiovascular benefit.

Type 2 diabetes

Inflammation impairs insulin signaling, contributing to insulin resistance. A 2020 meta-analysis in Diabetes Care found that the most anti-inflammatory diets (lowest DII) were associated with a 25 percent lower risk of developing type 2 diabetes. In people with existing diabetes, anti-inflammatory diets improve A1C and reduce the need for medication. Use our A1C Calculator to track your blood sugar status.

Supplements: what works and what does not

Whole foods are superior to supplements for anti-inflammatory effects, because the benefit comes from the food matrix, not isolated compounds. A few supplements have evidence for specific situations.

• Omega-3 (EPA plus DHA): 1 to 4 g/day for people who do not eat fish. Reduces CRP and cardiovascular risk. Prescription omega-3 (Vascepa) has FDA approval for cardiovascular risk reduction.
• Curcumin: The active compound in turmeric. Has modest evidence for reducing CRP and joint pain, but absorption is poor. Pair with black pepper (piperine) or use a formulated product (Meriva, Theracurmin).
• Vitamin D: Low vitamin D is associated with higher inflammation, but supplementation in people with normal levels does not consistently reduce CRP. Test before supplementing.
• Antioxidant supplements (vitamin E, beta-carotene, vitamin C in high doses): No consistent benefit in trials; high-dose beta-carotene increased lung cancer risk in smokers. Get antioxidants from food, not supplements.

Building an anti-inflammatory plate

The anti-inflammatory plate is a slight reframing of the Mediterranean plate. Aim for:

• Half the plate: colorful vegetables, with at least one cruciferous serving per day
• A quarter of the plate: protein, prioritizing oily fish 2 to 3 times per week, with legumes, poultry, and eggs on other days
• A quarter of the plate: whole grains or starchy vegetables (oats, barley, quinoa, sweet potato)
• Added fat: extra-virgin olive oil as the primary cooking and dressing fat
• A handful of nuts per day, especially walnuts
• Berries daily, other fruit 2 to 3 times per day
• Herbs and spices liberally, especially turmeric, ginger, and cinnamon
• Limit red meat to 1 to 2 times per month; avoid processed meat
• Limit added sugar to under 25 g per day; avoid sweetened beverages
• Limit ultra-processed foods to occasional use

The bottom line

The anti-inflammatory diet is the Mediterranean diet with extra emphasis on omega-3 fish, polyphenol-rich berries and olive oil, fiber-rich legumes and whole grains, and herbs and spices. Avoid refined carbohydrate, added sugar, fried foods, ultra-processed foods, and processed meat, which drive chronic inflammation and chronic disease. The effect on inflammatory markers (CRP, IL-6) is measurable in weeks, and the effect on cardiovascular, metabolic, and cognitive outcomes is substantial over years. Use the Omega-3 Calculator, Fiber Calculator, and Mediterranean Diet Score Calculator to track the components that matter most.