Condition

Crohn's Disease

Crohn's disease is a form of inflammatory bowel disease in which ongoing inflammation can strike any part of the digestive tract, most often the end of the small intestine. Vitamin D and omega-3 fatty acids have the strongest evidence among supplements, rated moderate, since low vitamin D is very common and omega-3s may calm inflammation. Tiny studies of glutamine, curcumin, and cannabis found no clear difference, so those remain very limited.

Sources: PMID 22038507; PMID 10850950

Supplements studied: 6
Graded outcomes: 4
Trials: 9
People studied: 520

Evidence by supplement

Strong
Moderate
Limited
Very limited

6 supplements

Glutamine

Glutamine: outcomes studied for Crohn's Disease
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Crohn's Disease Symptoms No effect		NoneNo effect	3 studies	56 people
Studies that measured crohn's disease symptoms Glutamine and whey protein improve intestinal permeability and morphology in patients with Crohn's disease: a randomized controlled trialDig Dis Sci · PMID 22038507 Glutamine supplementation and intestinal permeability in Crohn's diseaseJPEN J Parenter Enteral Nutr · PMID 10850950 Effect of long-term oral glutamine supplements on small intestinal permeability in patients with Crohn's diseaseJPEN J Parenter Enteral Nutr · PMID 9888411

Conjugated Linoleic Acid

Conjugated Linoleic Acid: outcomes studied for Crohn's Disease
Grade	Outcome	Effect	Size	Studies	People
	C-Reactive Protein (CRP) No effect		NoneNo effect	1 study	10 people
Studies that measured c-reactive protein (crp) Conjugated linoleic acid increased C-reactive protein in human subjectsBr J Nutr · PMID 16277783
	Interleukin 2	Improves (the measure goes up)		1 study	10 people
Studies that measured interleukin 2 Conjugated linoleic acid modulates immune responses in patients with mild to moderately active Crohn's diseaseClin Nutr · PMID 22521469
	Crohn's Disease Symptoms	Improves (the measure goes down)			10 people
	Interleukin 6	Improves (the measure goes down)			10 people
	Subjective Well-Being	Improves (the measure goes up)			10 people
	TNF-Alpha	Improves (the measure goes down)			10 people

Cannabis

C-Reactive Protein (CRP)
Hemoglobin: improves
Crohn's Disease Symptoms: improves

Cannabis: outcomes studied for Crohn's Disease
Grade	Outcome	Effect	Size	Studies	People
	C-Reactive Protein (CRP) No effect		NoneNo effect		21 people
	Hemoglobin	Improves (the measure goes up)		1 study	21 people
Studies that measured hemoglobin Cannabis induces a clinical response in patients with Crohn's disease: a prospective placebo-controlled studyClin Gastroenterol Hepatol · PMID 23648372
	Crohn's Disease Symptoms	Improves (the measure goes down)			21 people
	Hematocrit	Improves (the measure goes up)			21 people
	White Blood Cell Count	Improves (the measure goes up)			21 people

Curcumin

Crohn's Disease Symptoms
Ulcerative Colitis Symptoms: improves

Curcumin: outcomes studied for Crohn's Disease
Grade	Outcome	Effect	Size	Studies	People
	Crohn's Disease Symptoms No effect		NoneNo effect		10 people
	Ulcerative Colitis Symptoms	Improves (the measure goes down)		2 studies	10 people
Studies that measured ulcerative colitis symptoms Curcumin therapy in inflammatory bowel disease: a pilot studyDig Dis Sci · PMID 16240238 Curcumin for the clinical treatment of inflammatory bowel diseases: a systematic review and meta-analysis of placebo-controlled randomized clinical trials.Front Nutr · PMID 40196017

Cannabidiol (CBD)

Crohn's Disease Symptoms: improves

Cannabidiol (CBD): outcomes studied for Crohn's Disease
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Crohn's Disease Symptoms	Improves (the measure goes down)		1 study	20 people
Studies that measured crohn's disease symptoms Low-Dose Cannabidiol Is Safe but Not Effective in the Treatment for Crohn's Disease, a Randomized Controlled TrialDig Dis Sci · PMID 28349233

Whey Protein

Intestinal Permeability: improves

Whey Protein: outcomes studied for Crohn's Disease
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Intestinal Permeability	Improves (the measure goes up)			30 people

Key findings

Crohn's Disease SymptomsGlutamine
C-Reactive Protein (CRP)Conjugated Linoleic Acid

The Crohn's Disease Supportive Care protocol

2 primary supplements · 4 supporting supplements

Vitamin D2,000–4,000 IU daily (higher doses may be needed based on levels)
Omega-3 Fatty Acids2–4 g EPA+DHA daily

See the full protocol

Shop the evidence-backed picks

Support alongside medical care. These supplements are not a treatment for Crohn's Disease. If you are being treated for it, talk to your clinician before adding one: supplements can interact with medicines.

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Studies cited

3 studies from PubMed

A Randomized Trial Comparing the Specific Carbohydrate Diet to a Mediterranean Diet in Adults with Crohn's DiseaseGastroenterology · PMID 34052278
The Specific Carbohydrate Diet and Diet Modification as Induction Therapy for Pediatric Crohn's Disease: A Randomized Diet Controlled TrialNutrients · PMID 33291229
Dietary Interventions for the Treatment of Inflammatory Bowel Diseases: An Updated Systematic Review and Meta-analysis.Clin Gastroenterol Hepatol · PMID 36470529