Acute vs Chronic Inflammation

Acute inflammation

Inflammation is the body's response to an illness, injury or something that does not belong in the body, and Cleveland Clinic calls it a normal and important process that allows healing. [1] Acute inflammation is sudden and temporary, lasting from a few hours to a few days. [1] Typical signs are flushed skin, pain or tenderness in the affected area, swelling and heat. [1] MedlinePlus explains that when acute (sudden) and short, inflammation is helpful, for example in stopping infection around a cut. [2]

Chronic inflammation

Chronic inflammation continues for months or years, with the body sending inflammatory cells even when there is no danger. [1] MedlinePlus says that if inflammation lasts too long it can damage healthy tissue, and that it is most often caused by certain autoimmune disorders, or by repeated tissue injury or irritation, such as from smoking or chemicals in the environment. [2]

A separate idea is systemic chronic inflammation (low-grade, body-wide). A 2019 Perspective in Nature Medicine proposed that social, environmental and lifestyle factors, including infections, physical inactivity, poor diet, environmental and industrial toxicants and psychological stress, can promote it, and linked it to diseases such as cardiovascular disease, diabetes and cancer. [3] This is an expert synthesis and a research framework. It does not show that any one product or habit lowers disease risk by "lowering inflammation".

Another review argues that tissue stress or malfunction can set off an intermediate response called para-inflammation, probably responsible for chronic inflammatory conditions linked to modern diseases. [4] These are hypotheses about mechanism, not proven treatment targets.

Side by side

Chronic inflammation symptoms overlap with many other problems. Cleveland Clinic's list includes fatigue, joint pain, rash and digestive trouble, none of which is specific to inflammation. [1] That is a reason to see a clinician, not to self-diagnose.

What the CRP test does and does not say

C-reactive protein (CRP) is made by the liver in response to inflammation, and a blood test shows how much inflammation is present, not what is causing it. [2] MedlinePlus lists infections, bowel disease, autoimmune disorders, lung disease, smoking and pollution as causes of high CRP, and notes that levels can also be linked to insomnia, depression, menopause hormone therapy, obesity and sex. [2] Some medicines can also affect results, so tell your provider about supplements and drugs you take. [2] A CRP value is a biomarker, not a diagnosis. See inflammatory panels and their limits and biomarkers vs clinical outcomes.

A trial that tested the inflammation idea directly

The CANTOS trial randomized 10,061 people with a previous heart attack and a high-sensitivity CRP of 2 mg/L or more to canakinumab (an antibody that blocks interleukin-1 beta) or placebo. [5] Canakinumab lowered CRP without changing cholesterol. [5] At a median 3.7 years, the 150 mg dose lowered the rate of the main cardiovascular endpoint (hazard ratio 0.85, 95% CI 0.74 to 0.98), but the 50 mg dose did not, and canakinumab caused more fatal infections, with no difference in all-cause death. [5] The trial was funded by Novartis. [5]

What this shows: in a selected group and with a prescription antibody targeting a specific pathway, reducing a particular inflammatory signal changed clinical outcomes, with a safety cost. What it does not show: that lowering CRP by other means, such as supplements, foods or devices, has the same effect. Dietary evidence is on nutrition and inflammation research; see also claim check: reduces inflammation means improves health.