What Causes Inflammation in the Body?

Inflammation is your immune system’s response to a threat. When you cut your finger or catch a cold, your body sends immune cells to the area to fight infection and repair damage. That short-term inflammation is helpful and fades once the job is done. The problem is chronic inflammation, which happens when the immune response stays switched on for months or years even though there is no injury or infection to fight.

Chronic inflammation is usually driven by everyday factors rather than one event. The most common causes are ongoing stress, short or disrupted sleep, excess belly fat and insulin resistance, an imbalance in gut bacteria, low physical activity, diets heavy in processed foods, regular alcohol use, smoking, and exposure to certain toxins. Many of these are hidden stressors that people do not connect to inflammation: years of constant responsibility, sleeping lightly and waking at 3 a.m., running on coffee and skipped meals, and digestive problems that have been around so long they feel normal.

Chronic inflammation often has no single obvious symptom. It tends to show up as a pattern, such as fatigue, joint aches, digestive problems, skin flare-ups, brain fog, low mood, or weight gain around the middle. Over time, it is linked to many long-term conditions, including heart disease, type 2 diabetes, and autoimmune disease. Finding which drivers are active in your body is the first step toward calming it.

Key Points

  • Short-term inflammation is protective: It helps the body fight infection and heal injuries, then fades.

  • Chronic inflammation is the problem: The immune response stays active for months or years without a real threat.

  • Everyday factors drive most chronic inflammation: Stress, poor sleep, belly fat, gut imbalance, inactivity, diet, alcohol, smoking, and toxins.

  • Belly fat and insulin resistance feed inflammation: Deep belly fat is hormonally active and releases inflammatory signals.

  • Your gut plays a central role: Much of the immune system sits in the gut, and gut imbalance is a recognized cause of chronic inflammation.

  • Symptoms are often vague: Fatigue, aches, digestive problems, skin issues, brain fog, and low mood are common.

  • Blood tests can measure inflammation but not its cause: A CRP test shows how much inflammation is present, not where it comes from.

  • Calming inflammation means addressing the drivers: A plan aimed at your specific causes works better than a generic anti-inflammatory checklist.

Understanding Inflammation

Cleveland Clinic describes two types of inflammation. Acute inflammation is sudden and temporary, the immune response to a new injury or infection, and usually lasts hours to days. Chronic inflammation happens when the body keeps sending inflammatory cells even though there is no real threat, and it can last months or years, with periods of improvement and flare-ups.

Acute inflammation is easy to recognize: redness, swelling, heat, and pain around an injury, or a fever with an infection. Chronic inflammation is harder to see. It works quietly in the background, affecting blood vessels, joints, the gut, the brain, and how the body handles blood sugar. Many people live with it for years without knowing it is there.

Chronic inflammation is also self-reinforcing. Inflammation makes cells less responsive to insulin, which promotes belly fat, which releases more inflammatory signals. Inflammation disrupts sleep, and poor sleep raises inflammation. Gut problems trigger immune activity, and immune activity affects the gut. This is why chronic inflammation rarely has a single cause and why a single change rarely resolves it.

The Most Common Causes of Chronic Inflammation

Cleveland Clinic notes that most cases of chronic inflammation are caused by environmental and lifestyle factors. The most common include:

Chronic stress

Short-term stress hormones actually calm inflammation. When stress becomes constant, the body becomes less responsive to those signals, and inflammation can rise. Many people carry more stress than they realize: caregiving, high-pressure work, financial strain, relationship strain, and never having real time off. Physical stress counts too, including chronic dieting, overtraining without recovery, ongoing pain, and blood sugar swings from skipped meals.

Short or disrupted sleep

Sleep is when the body repairs and resets its immune system. Cleveland Clinic lists disrupted sleep and circadian rhythm among the causes of chronic inflammation. Short sleep, broken sleep, night shifts, late nights with screens, and untreated sleep apnea all keep the immune system on alert.

Belly fat and insulin resistance

Not all body fat behaves the same. Cleveland Clinic explains that visceral fat, the deep fat around your organs, is hormonally active and linked to insulin resistance, type 2 diabetes, and heart disease. It releases inflammatory substances into the body. Insulin resistance and inflammation feed each other, so improving one usually helps the other.

Gut imbalance

A large share of your immune system sits in the lining of your gut. Cleveland Clinic explains that beneficial gut microbes help train the immune system, and that substances they produce help maintain the gut lining and reduce inflammation. When the balance of gut bacteria shifts, a state called dysbiosis, that protective effect weakens. Cleveland Clinic lists gut dysbiosis among the causes of chronic inflammation. Repeated antibiotics, long-term acid reducers, a low-fiber diet, alcohol, and chronic stress can all disrupt gut balance.

Diet

Diets high in processed foods, added sugar, refined carbohydrates, trans fats, and salt are linked to higher inflammation, while diets rich in vegetables, fruits, fiber, and healthy fats are linked to lower inflammation. Food reactions can also play a role for some people. The composition of your diet matters, but no single food causes or cures inflammation on its own.

Low physical activity

Regular movement lowers inflammation over time, while long periods of sitting raise it. On the other hand, very intense exercise without enough rest, food, or sleep can push inflammation up. The goal is consistent activity your body can recover from.

Alcohol, smoking, and toxin exposure

Regular heavy drinking and tobacco use are well-known drivers of chronic inflammation. Exposure to certain chemicals and pollutants can also play a role. Environmental exposures matter for some people, but symptoms such as fatigue or joint aches are not specific to any one exposure, so a careful history should come before assuming a cause.

Autoimmune conditions and ongoing infections

In autoimmune conditions such as rheumatoid arthritis, lupus, psoriasis, Hashimoto’s thyroiditis, and inflammatory bowel disease, the immune system mistakenly targets the body’s own tissues. Lingering or recurrent infections can also keep inflammation active. These need proper diagnosis and medical management.

Signs that inflammation may be part of your picture

Cleveland Clinic lists symptoms of chronic inflammation that include:

  • Fatigue or insomnia

  • Joint pain or stiffness

  • Digestive problems such as diarrhea, constipation, or acid reflux

  • Skin rashes or mouth sores

  • Low mood, anxiety, or other mood changes

  • Weight gain or weight loss

  • Frequent infections

Each of these has many possible causes. They are worth paying attention to when several appear together.

How inflammation is measured

Blood tests can show whether inflammation is present. MedlinePlus explains that C-reactive protein (CRP) is made by the liver when there is inflammation in the body, and that a high-sensitivity CRP (hs-CRP) test can detect small increases and is used to estimate heart disease risk. CRP shows how much inflammation is present but not its cause or location, so results are interpreted alongside other tests, symptoms, and history. Other markers, such as erythrocyte sedimentation rate (ESR), fasting insulin and glucose, and stool markers such as calprotectin for gut inflammation, can help narrow down where inflammation is coming from.

Where medication fits

Anti-inflammatory pain relievers, steroids, and medications for autoimmune conditions can be important tools for controlling inflammation, especially during flares or in autoimmune disease. Regular use of over-the-counter anti-inflammatory pain relievers can also irritate the gut lining. Decisions about starting, stopping, or changing any medication belong with the provider who prescribes it. Do not stop a medication on your own, including steroids, which can be dangerous to stop suddenly.

How Agape approaches inflammation

At Agape Integrative Medicine, chronic inflammation is treated as a pattern to understand rather than a single number to lower. The first step is understanding your full health story: when your symptoms started, what changed around that time, which symptoms travel together, and what is happening with your sleep, stress, meals, digestion, skin, joints, mood, and, for women, your menstrual cycle and perimenopause symptoms. Laboratory testing, which may include inflammatory markers, blood chemistry, metabolic markers such as fasting insulin, thyroid and autoimmune-related testing, and gut testing, is used when it helps answer a specific question. The goal is to find which drivers are keeping inflammation active in your body and address them in a sensible order. From there, you get a personalized plan and an explanation of why each recommendation is being made. If you think inflammation may be behind how you feel, you can book a new patient appointment.

Who It’s For and Who Should Be Cautious

This information is most useful for adults who live with ongoing fatigue, aches, digestive problems, skin flare-ups, brain fog, or weight gain around the middle, especially when several occur together. It is also relevant for people with autoimmune conditions, insulin resistance, prediabetes, or a family history of heart disease, and for people who have been under long-term stress or sleeping poorly. People who want to understand what is driving inflammation in their body tend to do well with Agape’s functional medicine approach.

Some caution applies. Joint swelling, persistent rashes, ongoing digestive symptoms, and other signs of inflammation can point to autoimmune disease, infection, or other conditions that need medical diagnosis and treatment. If you have a diagnosed autoimmune or inflammatory condition, a functional medicine plan should work alongside the care you receive from your rheumatologist, gastroenterologist, or other specialist, not replace it. Be cautious of any program that promises to eliminate inflammation or cure autoimmune disease.

Risks, Side Effects, and Monitoring

The biggest risk is leaving chronic inflammation unaddressed. Cleveland Clinic links it to heart disease, type 2 diabetes, autoimmune diseases, certain cancers, depression, and neurodegenerative conditions. Because it often has vague symptoms, it is easy to overlook for years.

Common quick fixes carry their own risks. Taking over-the-counter anti-inflammatory pain relievers every day can cause stomach ulcers, kidney problems, and bleeding. Supplements marketed as anti-inflammatory can interact with medications, and some, such as high-dose turmeric or fish oil, can affect bleeding risk. Very restrictive “anti-inflammatory” diets can lead to nutrient gaps and more anxiety around food.

Monitoring helps show whether inflammation is calming. Inflammatory markers such as CRP can be rechecked at reasonable intervals, along with metabolic markers and any condition-specific tests. Symptoms such as energy, sleep, joint comfort, digestion, and skin often improve along the way and are worth tracking.

These are individualized decisions best made with a knowledgeable provider. Medications and supplements should not be started, stopped, or combined without guidance from the provider who prescribes them.

Safety

See a medical provider promptly if you have joints that are hot, red, and swollen, a persistent rash, ongoing diarrhea or blood in your stool, unexplained fever, night sweats, or weight loss, or swelling in your legs. Also seek care if you have been taking anti-inflammatory pain relievers regularly and notice stomach pain, black stools, or changes in urination.

Call 911 or go to the emergency room if you have chest pain, severe shortness of breath, a high fever with confusion or a stiff neck, a rapidly spreading red, hot, and painful area of skin, vomiting blood, or severe abdominal pain.

Do not stop or change any prescribed medication on your own.

Sources and Citations

Reviewed By Dr. Jordan Robertson, DC
Last updated: October 2026