This study is a review of research publications that investigated the effect of curcumin, an active ingredient in turmeric, on inflammatory bowel disease in humans. Various databases including PubMed, ALTMEDEX, and the Comprehensive Database of Natural Medicines were searched using key words like “turmeric,” “curcumin,” “inflammatory bowel disease,” “ulcerative colitis,” “Crohn’s disease” and other related key words to find studies conducted between 1980 and 2009. Studies have shown that when given together with conventional medicine, curcumin improves symptoms associated with bowel diseases. Moreover, it could reduce the dosage of medicines required for treatment of bowel diseases.
Turmeric has historically been used as a spice and a medicinal herb. It has also been used in the treatment of ailments ranging from respiratory disorders to cancers, with no reported side effects. It is a perennial herb containing curcuminoids. Curcumin interacts with many molecules in living cells. In case of digestive tract disorders, it can inhibit processes that lead to inflammation. By interacting with molecules of major cellular signaling pathways like interleukin-1beta (IL-1β) and mitogen-activated protein kinase (MAPK), curcumin inhibits the inflammatory cascades linked to gastrointestinal cancers. Inflammatory bowel disease causes stomachache, diarrhea, rectal bleeding, and fever. It is an immune system-related disorder involving cytokine molecules. Increased levels of nuclear factor-kappaB, NF-κB, lead to inflammation in the lining of the intestine in patients suffering from inflammatory bowel disease. Curcumin directly or indirectly inhibits the Cyclooxygenase-2 (COX-2) proteins, which play an important role in the inflammation cascade and lead to cancers. Curcumin leaves a little trace in the blood even after months of oral administration, suggesting poor absorption by tissues.
Out of all the clinical studies reviewed, two were assessed in detail. The first study tested the effect of curcumin on two types of inflammatory bowel disease, namely ulcerative proctitis and Crohn’s disease. Five patients, each with ulcerative proctitis and Crohn’s disease had participated in the study. Patients with ulcerative proctitis were already on medication, and were given two doses of 550 mg of curcumin per day for one month and three doses per day in the next month. Patients with Crohn’s disease were administered three doses of 360 mg of curcumin per day for a month, followed by four doses per day in the next two months. The second study tested the effect of curcumin together with the medicines sulfasalazine or mesalamine on 89 patients with ulcerative colitis. Placebo was administered to 44 patients, while 1,000 mg of curcumin was given twice a day to 45 patients for six months, together with the medicines.
- In the first study, the results of blood tests and biochemistry and inflammatory analysis were recorded before and after the study.
- Symptoms of patients with ulcerative proctitis improved considerably, reducing the need for medication after two months. Patients with Crohn’s disease showed a reduction in symptoms. They reported reduced stomach pain, cramping, etc.
- In the second study, eight patients from the placebo group suffered a relapse, while only two patients in the experimental group, who were administered with curcumin, relapsed. The symptoms decreased in the experimental group while they increased in the placebo group.
- Some side effects like bloating and hypertension were reported.
A study on a much larger scale is needed to test the effect of curcumin on inflammatory gastrointestinal diseases like Crohn’s disease and ulcerative proctitis. The placebo effect also needs to be tested with regard to Crohn’s disease. The researchers recommend testing higher doses, more than 2 grams of curcumin a day, in future studies.
Curcumin is found to be useful in the treatment of psoriasis, cancer, pancreatitis, etc. It is safe even when consumed in high doses. It is inexpensive, easily available, and generally tolerable by patients. Patients with preexisting conditions like gall stones should refrain from curcumin treatment as it leads to contraction of the gall bladder. Curcumin is known to prevent clumping of platelets in blood, thereby increasing the affectivity of anti-inflammatory drugs and preventing clotting in blood vessels. When taken together with standard drugs for inflammatory bowel disease, it is found to suppress relapses. It also helps in relieving the symptoms of ulcerative proctitis and Crohn’s disease.
For More Information:
Curcumin for Inﬂammatory Bowel Disease: A Review of Human Studies
Publication Journal: Alternative Medicine Review, 2011
By Rebecca A. Taylor; Mandy C. Leonard; Department of Pharmacy, Cleveland Clinic, Ohio
*FYI Living Lab Reports Are Summaries of the Original Research.