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Supplements for Inflammation: What Actually Lowers CRP in Trials, and What That Means

A supplement that lowers CRP, a blood marker of inflammation, hasn't been shown to prevent disease by doing so. Fish oil lowered CRP in pooled trials of people with health conditions (grade B, mixed), and curcumin lowered it a little (grade C). Weight loss and exercise lower CRP too. Fish oil and turmeric can add to bleeding risk on blood thinners, and turmeric has been linked to liver damage.

Published How we grade evidenceEditorial policy

Inflammation is your immune system's response to injury or infection, and in the short term it is normal and useful: the swelling around a sprain or the fever with flu. The kind people mean when they ask about supplements is chronic, low-grade inflammation, which shows up on blood tests as a slightly raised CRP (C-reactive protein, made by the liver) or IL-6 (interleukin-6, a signalling protein). This guide covers adults.

A lower CRP is a lab result, not a health benefit by itself. It shows you are less inflamed on paper. Only outcome trials show whether that means fewer heart attacks, less joint pain or longer life, and for supplements those trials are mostly missing or negative.

The short version

  • Losing weight and exercising (adults, many trials): both lower CRP; each kilogram lost went with about 0.13 mg/L less. Grade B (Selvin 2007; Fedewa 2017).
  • Fish oil (omega-3): CRP fell in pooled trials, mostly in people with health conditions; in a 4-year trial of 1,054 older adults from the general population, it did not change compared with a dummy pill. Grade B, mixed (Khabir 2026; Dong 2022).
  • Curcumin (turmeric extract, in randomized trials): CRP about 1.55 mg/L lower in pooled trials of adults not on anti-inflammatory drugs; some products also contained black pepper extract (piperine). Grade C (Ferguson 2021). Turmeric supplements have been linked to liver damage.
  • Ginger (pooled trials): lower CRP, with very inconsistent results. Grade C (Rjabi 2025).
  • Vitamin D (VITAL trial, 2,000 IU a day vs placebo): CRP 19% lower at 2 years but not at 4; autoimmune diseases 22% less common over about 5 years. Grade C, mixed for CRP; grade C for autoimmune disease (Dong 2022; Hahn 2022).

The grades in this guide for lifestyle steps, NAC, quercetin, green tea and vitamin D's effect on autoimmune disease are its own; our supplement pages don't grade these outcomes yet.

Option (who, compared with what)What trials foundSize of effectGrade
Weight loss (lifestyle and surgery studies)Lower CRPAbout 0.13 mg/L per kg lostB
Exercise training (83 controlled trials, 3,769 people)Lower CRP, even without weight lossSmallB
Fish oil (people with health conditions, pooled trials)Lower CRPMost consistent at 1 to 3 g EPA+DHA a dayB, mixed
Fish oil (1,054 older adults, general population, 1 g a day vs placebo)No changeNone over 4 yearsB, mixed
Curcumin (adults not on anti-inflammatory drugs, pooled trials; some products added black pepper extract)Lower CRPAbout 1.55 mg/LC
Vitamin D (1,054 older adults, vs placebo)Lower, then not19% at 2 years, none at 4C

What raises CRP, and what lowers it without supplements?

Grade B for weight loss, exercise and gum treatment. Body weight matters: across lifestyle and surgery studies, each kilogram lost went with CRP about 0.13 mg/L lower (Selvin 2007). In 83 controlled trials (3,769 people), exercise training lowered CRP, more so with fat loss but also without it (Fedewa 2017). Treating gum disease (periodontitis) lowered CRP by 0.69 mg/L at 6 months in pooled trials (Luthra 2023). In observational studies, poor sleep went with a slightly higher CRP (grade C) (Irwin 2016).

Does a lower CRP mean better health?

Not on its own. The clearest test came from a drug, not a supplement: in 10,061 people who had had a heart attack and a raised CRP, the injected antibody canakinumab cut CRP and modestly lowered heart attacks, strokes and heart deaths at one of its doses, without changing cholesterol (Ridker 2017). That shows inflammation can matter. It does not show that a capsule that trims CRP by a fraction does the same. For fish oil and the heart, see the fish oil guide; for heart risk overall, cardiovascular disease. If you take heart medicines, don't stop or swap any of them for a supplement without your prescriber.

Does fish oil help with inflammation?

Grade B, mixed: CRP fell mainly in people who already had a health condition. It stays at B rather than C because a large body of trials (96 in the latest review) agree on a small CRP drop in people with health conditions; the large VITAL trial in healthy older adults is why it is mixed. A 2026 review of omega-3 trials found EPA and DHA (the omega-3 fats in fish oil) lowered CRP, TNF-alpha and IL-6, particularly in participants with underlying health conditions, most consistently at 1 to 3 g a day of EPA plus DHA; the review did not report the drop in mg/L (Khabir 2026). In the VITAL trial, 1,054 adults from the general population, average age about 65, took 1 g a day of omega-3 or placebo, and CRP, IL-6 and TNF-alpha did not change at 2 or 4 years (Dong 2022). Our omega-3 page also shows B for a small CRP drop. In large heart trials, omega-3 supplements went with about 25% more atrial fibrillation (an irregular heartbeat), and more at doses above 1 g a day (Gencer 2021). The fish oil guide covers heart, joints and side effects; see also fish oil.

Does turmeric help with inflammation, and how long does it take?

Grade C: a lower CRP in short trials, on low-certainty evidence. Pooling trials in adults not taking anti-inflammatory medicines, curcumin lowered CRP by about 1.55 mg/L and IL-6 and TNF-alpha a little. Some of the products tested also contained piperine, a black pepper extract added to help absorption, and the authors said dose, length and form still need working out (Ferguson 2021). Many curcumin trials come from a small number of research groups, which is another reason to stop at C. Liver damage has been reported with turmeric and curcumin supplements, mostly "high-absorption" products, so stop and see a clinician if you get tiredness, nausea, poor appetite, dark urine or yellow skin or eyes (NCCIH). The turmeric guide has the pain and diabetes results; see curcumin.

Does vitamin D help with inflammation?

Grade C, mixed for CRP. In VITAL, 2,000 IU a day of vitamin D3 lowered CRP by 19% at 2 years, but not at 4, and did not change the other markers (Dong 2022). In trials of women after menopause, CRP fell by 0.65 mg/L (Jiang 2024). The outcome result is more interesting: in 25,871 adults followed for a median of 5.3 years, vitamin D cut new autoimmune diseases by 22% (hazard ratio 0.78), a borderline result (grade C, one trial) (Hahn 2022). Our vitamin D page shows D, no effect, for inflammation from a single study; the VITAL results above support C, mixed. Upper limit for adults: 4,000 IU (100 mcg) of vitamin D daily; above it, blood calcium can climb too high, so go higher only on your clinician's advice, with blood tests (NIH ODS; tally your stack). See the vitamin D guide.

Does ginger, NAC, resveratrol or quercetin lower inflammation?

  • Ginger: grade C. A 2025 review found ginger lowered CRP by 0.86 mg/L, and IL-6 and TNF-alpha, mostly in people with health conditions, with high variation between trials (Rjabi 2025); an earlier review agreed on CRP but found no change in IL-6 (Morvaridzadeh 2020). See ginger. Ginger for joint pain is in the joint pain guide.
  • NAC: grade C. Pooling trials of NAC by mouth, CRP fell by 0.61 mg/L and IL-6 slightly, with no effect on other markers and high variation between trials (Askari 2020). See the NAC guide and N-acetylcysteine.
  • Resveratrol: grade C. Pooled placebo-controlled trials found slightly lower hs-CRP and TNF-alpha, but not IL-6; several of the trials used grape or knotweed extracts containing resveratrol rather than resveratrol on its own (Koushki 2018). See resveratrol.
  • Quercetin: grade C. In 7 trials (one of them also tested quercetin with vitamin C), CRP fell by 0.33 mg/L, mainly at 500 mg a day or more (Mohammadi-Sartang 2017); our quercetin page shows no effect on IL-6.

Do green tea, glycine, spirulina, probiotics or sea moss help?

  • Green tea: grade C, no clear CRP effect. Pooled trials found green tea did not lower CRP; IL-6 rose and TNF-alpha fell (Haghighatdoost 2019). Concentrated green tea extract is among the supplements most often linked to liver injury in the US (Navarro 2017). See green tea extract.
  • Glycine: grade C. In one trial, 74 adults with type 2 diabetes took 5 g of glycine or a dummy pill a day for 3 months; TNF receptor 1, a blood marker linked to inflammation, fell with glycine, and HbA1c was lower (Cruz 2008). Glycine has no official upper limit. A 16-week trial in 24 older adults gave glycine together with NAC and found lower inflammation markers, but with the two combined, that effect can't be credited to glycine (Kumar 2023). See glycine.
  • Spirulina: not graded. A pooling of 7 small trials (283 people) reported CRP 0.55 mg/L lower, with very inconsistent results (Shahraki Jazinaki 2025), and one of its trials is from an author group whose work we set aside under our grading rules. See spirulina.
  • Probiotics: not graded for CRP. Our probiotics page shows B for lower CRP, but the pooled analyses behind it include trials from that same excluded author group. Results also depend on the strain and the condition; see do probiotics work?
  • Sea moss: no trial has tested sea moss for inflammation in people. In a 2026 test of 66 sea moss products bought online, dried products contained arsenic, cobalt and mercury, and bacteria including Salmonella were found among the samples (Rejuso 2026).

What if your inflammation has a name?

Arthritis, bowel disease and other inflammatory diseases have trials that measured the disease itself, and those beat any CRP result. For osteoarthritis, an enriched boswellia extract lowered pain scores by 17 points out of 100 over 90 days in 2 trials (85 people) (grade B) (Cameron 2014); turmeric is graded in the joint pain guide and on boswellia. For rheumatoid arthritis, osteoarthritis, ulcerative colitis and Crohn's disease, use those pages, and never swap a prescribed medicine for a supplement.

What we'd skip

  • "Anti-inflammatory" blends sold to lower CRP: no blend has outcome trials, and the supplements above, mostly tested on their own, lowered CRP by about 0.3 to 1.6 mg/L in pooled trials (Mohammadi-Sartang 2017; Ferguson 2021).
  • Fish oil to lower CRP if you are healthy: no change over 4 years in VITAL (Dong 2022).
  • Sea moss: no human trials, and contaminants in tested products (Rejuso 2026).

Safety and interactions

  • Bleeding: fish oil and turmeric may add to bleeding risk on blood thinners; see supplements and blood thinners, can I take fish oil with Eliquis? and can I take turmeric with Eliquis?. In 12 healthy men given a single dose of warfarin, ginger did not change the INR or platelet clumping (Jiang 2005); that was a one-dose test in healthy volunteers, not patients on long-term warfarin. Ask your prescriber or pharmacist before adding any of them.
  • Liver and gallbladder: liver damage has been reported with turmeric and curcumin supplements, mostly "high-absorption" products (NCCIH). Stop and see a clinician if you get tiredness, nausea, poor appetite, dark urine or yellow skin or eyes. Don't take turmeric supplements with gallstones, a blocked bile duct or liver disease (European Medicines Agency). Green tea extract is also one of the supplements most often linked to liver injury in the US (Navarro 2017). See supplements and your liver.
  • Fish oil and heart rhythm: in large heart trials, omega-3 supplements went with more atrial fibrillation (an irregular heartbeat): about 25% more overall, and more at doses above 1 g a day (Gencer 2021). If you have had atrial fibrillation or palpitations, ask your doctor first.
  • NAC with nitroglycerin: severe headache and low blood pressure; see the NAC guide.
  • Diabetes medicines: curcumin lowered blood sugar in diabetes trials (see the turmeric guide); test your blood sugar more often if you add it, and don't skip a medicine for it.
  • Stacks: many "inflammation" products combine turmeric, ginger and vitamin D. Check your stack.
  • Pregnancy and breastfeeding: NIH says turmeric supplements may be unsafe in pregnancy (NCCIH); ask your midwife or obstetric team before any of these. For anyone under 18, the child's own doctor should decide.

When to see a doctor

  • Go now for a hot, red, swollen joint with fever (possible joint infection or gout), or a high fever with confusion or a fast heartbeat (possible serious infection).
  • Soon for joints swollen for weeks, morning stiffness lasting more than about 30 minutes, unexplained weight loss, night sweats, a fever that keeps coming back, or blood in your stool. These can point to rheumatoid arthritis or other autoimmune disease, inflammatory bowel disease, a hidden infection or cancer.
  • Soon for dark urine, yellow skin or eyes while taking turmeric or green tea extract (possible liver injury), or a racing or irregular heartbeat while taking fish oil.
  • For a very high CRP on a blood test: ask what is causing it rather than treating the number with supplements.

Don't stop a prescribed medicine on your own; ask the prescriber or pharmacist. If you are pregnant, breastfeeding or under 18, get a clinician's advice first.

FAQ

What is the best supplement for inflammation? None has been shown to prevent or treat inflammation-related disease, apart from one large trial that found fewer new autoimmune diagnoses with vitamin D (grade C, one trial). Fish oil (in people with health conditions, grade B, mixed) and curcumin (grade C) lowered CRP a little in pooled trials, but weight loss and exercise also lower it.

Does fish oil help with inflammation? It lowered CRP in pooled trials, mostly in people with health conditions, but 1 g a day did not change CRP over 4 years in 1,054 older adults from the general population in VITAL (grade B, mixed).

How long does turmeric take to reduce inflammation? Pooled trials found a lower CRP, a blood marker, but the reviewers said the dose, length of treatment and form that work best still need confirming (grade C). For arthritis pain, see the joint pain guide.

Does NAC help with inflammation? In pooled trials, NAC by mouth lowered CRP by 0.61 mg/L and IL-6 slightly, with high variation between trials (grade C). Don't combine it with nitroglycerin without your prescriber's OK.

Does sea moss help with inflammation? No trial has tested it in people. Dried products bought online contained arsenic, cobalt and mercury, and bacteria including Salmonella were found among samples.

Sources

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