Curcumin is a supplement that is taken primarily for its antioxidant and anti-inflammatory properties (1).
Supplementation may be helpful in the treatment of arthritis pain, cardiovascular conditions and symptoms of depression and anxiety. Curcumin is a polyphenolic compound derived from turmeric — the popular spice that has been used in India for thousands of years.
Worldwide, there are over 1000 published animal and human studies in which the effects of curcumin on various diseases have been examined (2). Many have yielded impressive results.
Medical experts stress, however, the need for robust human clinical trials to gain a clearer understanding of the efficacy of supplementation as well as any safety concerns, especially with long-term use.
1 Curcumin is a potent antioxidant. To understand curcumin’s role as an antioxidant, it helps to know a little more about free radicals and oxidative stress.
Free radicals are highly reactive molecules with unpaired electrons. They are produced continuously in the cells as part of normal cellular function; however, excess production of free radicals has been shown to play a role in the development of many disease and conditions.
When there is an imbalance between the production of free radicals and antioxidants — man-made or natural substances that help prevent free radicals from damaging cells — a process known as oxidative stress occurs. Oxidative stress can damage every component of cells—proteins, enzymes, and even DNA, which can lead to diseases and medical conditions, such as cancer, arthritis, autoimmune disorders, cardiovascular and neurodegenerative diseases (4).
Studies demonstrate curcumin’s ability to scavenge different forms of free radicals, such as reactive oxygen and nitrogen species (5). In addition, curcumin boosts the activity of the body’s own antioxidant enzymes.
2 Curcumin helps treat inflammation. Chronic inflammation has been linked to the development of a range of diseases — from Alzheimer’s disease to cardiovascular disease to allergies and asthma.
Curcumin has been shown to block NF-κB — a molecule that travels into the nuclei of the cells and turns on genes related to inflammation (6).
According to the Alternative Medicine Review, clinical trials (based on early cell cultures and animal research) indicate curcumin may be a future therapeutic agent for the treatment of such inflammatory diseases as inflammatory bowel disease, pancreatitis and arthritis (7).
It may also help in the management of exercise-induced inflammation and muscle soreness, thus enhancing recovery and performance in active people (8).
Furthermore, the results of a study published in the journal, Oncogene, revealed that curcumin (along with resveratrol, celecoxib and tamoxifen) was more potent as an anti-inflammatory than aspirin and ibuprofen (9).
3 Curcumin may play a protective role against cardiovascular disease. According to a 2012 review of scientific literature, there is substantial evidence to suggest that curcumin can exert a cardioprotective role.
The authors of the article published in the Indian Journal of Biochemistry & Biophysics, specifically noted the compound’s protection against atherosclerosis (build-up of fats, cholesterol and other substances in and on the artery walls), cardiac hypertrophy (abnormal enlargement, or thickening, of the heart muscle), heart failure and endothelial dysfunction (a term that refers to impaired functioning of the lining of blood vessels) 10.
When damage occurs to the endothelium (a result of high blood pressure, diabetes, high cholesterol and smoking) there is an increased risk of developing cardiovascular disease, heart attack and stroke (11).
4 Curcumin may help prevent and treat symptoms of arthritis. Arthritis is inflammation of the joints and can affect one or more joints in the body.
A 2010 clinical trial found that a turmeric supplement called Meriva (standardized to 75 percent curcumin combined with phosphatidylcholine) was clinically effective in the management and treatment of osteoarthritis. Researchers specifically noted that osteoarthritis symptoms decreased by 58 percent, walking distance on the treadmill test was prolonged from 76 minutes to 332 minutes and C-reactive protein (CRP) levels — markers of inflammatory status — decreased (12).
In a small 2012 pilot study, a curcumin product called BCM-95 reduced joint pain and swelling in patients with active rheumatoid arthritis better than diclofenac sodium, a nonsteroidal anti-inflammatory drug (NSAID) used to relieve pain, inflammation and joint stiffness caused by arthritis (13).
5 Curcumin may help prevent and treat neurodegenerative diseases such as Alzheimer’s disease. According to the Alzheimer’s Association, an estimated 5.8 million Americans are living with Alzheimer’s disease. This number will escalate rapidly in coming years, as the population of Americans age 65 and older is projected to grow from 55 million in 2019 to 88 million by 2050 (14).
The process through which Alzheimer’s disease degrades the nerve cells is believed to involve certain properties: inflammation, oxidative damage and most notably, the formation of beta-amyloid plaques.
In an animal study, the levels of beta-amyloid plaques in mice with Alzheimer’s disease that were given low doses of curcumin were decreased by around 40 percent in comparison to those that were not treated with curcumin (15).
A 2018 study in The American Journal of Geriatric Psychiatry also revealed promising results. The memory function of participants (between the ages of 50 and 90) who took 90 mg of the curcumin supplement (Theracurmin) twice a day, improved by 28 percent on average.
The duration of the study was 18 months and the participants all had mild memory problems, but did not have Alzheimer’s disease or other form of dementia (16).
6 Curcumin shows promise in effectively treating neuropsychiatric disorders. A 2017 systemic review of in vitro, animal and human studies investigating the potential of curcumin as a treatment for neuropsychiatric disorders, concluded that curcumin is a promising, natural agent. Out of the range of neuropsychiatric disorders reviewed — major depressive disorder, post-traumatic stress disorder, obsessive-compulsive disorder, bipolar disorder, psychotic disorders and autism — the greatest support for the efficacy of curcumin is for the treatment of major depressive disorder (17).
However, further research utilizing robust, clinical designs are essential.
A 2017 meta-analysis of six clinical trials with a total of 377 patients comparing the use of curcumin to placebo found that it appears to be safe, well-tolerated and efficacious among depressed patients. Significant anti-anxiety effects were also reported in three of the trials (18).
7 Curcumin may improve symptoms of gastrointestinal (GI) disorders. Curcumin’s anti-inflammatory benefits can support people with such GI disorders as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), Crohn’s disease, and ulcerative colitis.
As part of a study to evaluate curcumin’s effect on treating IBS, 207 volunteers were randomized to receive one or two tablets of a standardized turmeric extract daily for eight weeks. IBS prevalence decreased significantly in both groups between screening and baseline (41 percent and 57 percent), with a further significant drop of 53 percent and 60 percent between baseline and after treatment, in the one- and two-tablet groups respectively.
A post-study analysis revealed a reduction in abdominal pain/discomfort score by 22 percent and 25 percent in the one- and two-tablet group respectively (19).
8 Curcumin may play a role in fighting cancer. Curcumin has been shown to suppress multiple signaling pathways and inhibits cell proliferation, invasion, metastasis (the spread of cancer cells from where they started to other parts of the body) and angiogenesis (the formation of new blood vessels) 20.
Researchers are particularly interested in the role curcumin plays in fighting colon cancer. Finding ways to reduce aberrant crypt foci (clusters of abnormal tube-like glands in the lining of the colon and rectum that form before colorectal polyps) is important as they are one of the earliest changes that can be seen in the colon that may lead to cancer.
After a 30-day study of 44 men with eight or more aberrant crypt foci, researchers found that 4 grams of curcumin per day reduced the number of lesions by 40 percent (21).
According to Memorial Sloan Kettering Cancer Center, oral curcumin administered to colorectal cancer patients during the pre-surgery waiting period improved weight loss, muscle wasting and the general health of patients (22).
However, recent experiments suggest turmeric may interfere with the activity of some chemotherapy drugs, so the question remains whether curcumin is helpful or harmful during chemotherapy.
9 Curcumin may be effective in controlling signs and symptoms of oral mucositis. Oral mucositis is a common complication of cancer treatments, particularly chemotherapy and radiation. High dose chemotherapy, and localized high dose radiation therapy to the head and neck region can cause the mucosal lining of the mouth to break down, leading to open sores (23).
According to a 2019 systemic review of four randomized and one nonrandomized clinical trial, patients treated with turmeric/curcumin applied topically as a gel or mouthwash, experienced a reduction in pain, erythema (redness and irritation) intensity, and ulcerative areas (24).
10 Curcumin may help treat non-alcoholic fatty liver disease. Non-alcoholic fatty liver disease (NAFLD) is a common condition that affects 14 percent to 30 percent of the general population (25), and is characterized by too much fat stored in liver cells. Nonalcoholic steatohepatitis, a potentially serious form of the disease, is marked by liver inflammation, which may progress to scarring and irreversible damage.
A 2019 systematic review and meta-analysis of randomized controlled trials revealed that turmeric/curcumin supplementation reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) liver enzyme levels. Elevated levels of these enzymes are associated with liver damage and are used to screen for and/or monitor liver disease (26).
Further clinical trials are needed to confirm these findings.
11 Curcumin may play a beneficial role in skin diseases. Curcumin protects the skin by combating free radicals and reducing inflammation. Early evidence suggests that it may help in the treatment of psoriasis (red, scaly patches of skin), skin cancer (particularly squamous cell carcinoma), scleroderma (autoimmune condition that causes the skin and connective tissue to thicken) and vitiligo (patchy loss of skin coloring) 27.
Curcumin may also help heal skin wounds and cuts. A review of recent literature on the wound healing properties of curcumin provided evidence for its ability to enhance the various stages of the natural wound healing process, namely, enhancing granulation tissue formation, collagen deposition, tissue remodeling and wound contraction (28).
Most studies performed so far, have been limited to animal models. Human studies are needed.
12 Curcumin may provide relief from dental problems. Early results highlight the possibility of curcumin being used for the prevention and treatment of several dental conditions. Of particular note is its ability to eliminate dental pain and swelling and providing relief from gingivitis (inflammation of the gums) and periodontitis (inflammation of the gums and supporting structures of the teeth) 29.
In addition, research shows that turmeric mouthwash (prepared by dissolving curcumin extract in distilled water and peppermint oil) could be an affective adjunct to chlorhexidine gluconate (an antimicrobial rinse often used to treat the beginning stages of gum disease) in the prevention of plaque and gingivitis.
There is currently no evidence that lower amounts of curcumin (when taken short-term) cause serious side effects in healthy humans. Curcumin was found to be pharmacologically safe in human clinical trials with doses up to 10 g/day. A phase 1 human trial with 25 subjects using up to 8000 mg of curcumin per day for three months found no toxicity from curcumin.
Human studies on the long-term effects of curcumin supplementation are lacking, and, therefore, are unknown.
Higher doses of curcumin may cause several side effects.
1 Curcumin may cause gastrointestinal complaints such as nausea, bloating and diarrhea. It might also make stomach problems such as gastroesophageal reflux disease (GERD) worse. Do not take turmeric if it worsens symptoms of GERD (30).
2 Curcumin may cause skin problems. A few cases of allergic contact dermatitis from curcumin have been reported, when applied topically (31).
3 The chronic use of curcumin may cause liver toxicity. For this reason, turmeric/curcumin products should probably be avoided by individuals with liver disease, heavy drinkers and those who take prescription medications that are metabolized by liver.
4 Curcumin may worsen gallbladder problems. Those who have gallstones or a bile duct obstruction, should not take curcumin supplements.
5 Curcumin may cause bleeding problems. Taking curcumin might slow blood clotting. Individuals who take blood thinners such as warfarin (Coumadin) or are about to have surgery, should avoid use (as it might cause extra bleeding during and after surgery) 32.
6 Curcumin may cause kidney stones. Consumption of curcumin can increase urinary oxalate levels; excess oxalate in the urine increases the risk of kidney stone formation in predisposed individuals.
One of the major problems with ingesting curcumin by itself is its poor bioavailability, which appears to be primarily due to poor absorption, rapid metabolism and rapid elimination.
Researchers have found that one of the ways to improve the absorption of curcumin is to enhance it with piperine, the major active component of black pepper, which has been shown to improve the absorption of curcumin by 2,000 percent (33).
Curcumin is available in several forms including capsules, tablets, ointments and energy drinks.
The recommended dosage varies, depending on what is being treated. For the treatment of osteoarthritis, the Arthritis Foundation recommends 400 mg to 600 mg capsules, three times per day; or 0.5 g to 1 g of powdered root up to 3 g per day.
For the treatment of rheumatoid arthritis, 500 mg taken two times per day is the recommendation (34). Curcumin is usually taken together with food.
For recommended doses to treat other conditions, it is best to consult with a medical professional.
What is the difference between curcumin and turmeric? Turmeric is a spice made from the root of Curcuma longa, a flowering plant of the ginger family. Curcumin is the main active component in turmeric. Curcumin is extracted to produce supplements that have a much higher potency than turmeric. Some studies suggest that turmeric has benefits, and it is possible that it has benefits that curcumin alone does not, but more research on this is needed.
How much curcumin is found in turmeric powder? Curcumin makes up 3 percent of dry turmeric by weight.
Can I reap the benefits of curcumin by adding turmeric to my diet? The curcumin content of turmeric is not that high. As mentioned previously, it is only around 3 percent by weight. Most studies are using turmeric extracts that contain mostly curcumin itself, with dosages usually exceeding 1 gram (1,000 mg) per day. It would be very difficult to reach these levels just using the turmeric spice in cooking (there are about 200 milligrams of curcumin in one teaspoon of ground turmeric).
However, medical experts do believe that when turmeric is consumed in foods for many years, it may offer some type of long-term protective effects against oxidative stress and inflammation. But for therapeutic use, simple dried turmeric is probably of limited value. Therefore, if you want to experience the full effects, you need to take a supplement that contains higher amounts of curcumin. As mentioned earlier, however, it is best to consult with a medical professional before adding curcumin supplements to your diet, especially high doses.
What are curcuminoids? Turmeric contains a variety of phytochemicals, including curcuminoids, which are a group of polyphenolic compounds. Of the three main curcuminoids — curcumin, demethoxycurcumin and bisdemethoxycurcumin — curcumin is the most active and abundant and has been shown to have a wide range of therapeutic effects.
Should I take curcumin supplements daily? Although this active compound offers many scientifically-proven health benefits, it is important to keep in mind that studies performed so far have primarily focused on short-term use. Studies on the long-term effects of daily curcumin supplementation are lacking.
How should curcumin be taken? Curcumin is fat-soluble, meaning it will not be absorbed as well without the presence of fat or oil. It is recommended to take supplements with or after a meal.
What is bioavailability? It is the ability of a nutrient or other substance to be absorbed and used by the body. When a nutrient is poorly bioavailable, its digestion, its absorption or both can be much more difficult and much less predictable.
If curcumin is difficult to absorb, what can be done? Researchers have found that using a standardized extract of curcumin from turmeric root can greatly boost absorption. Standardization concentrates the plant’s most effective compounds — in this case, curcumin. Most curcumin supplements on the market are “95 percent standardized curcumin” products.
What should I look for on a curcumin supplement label?
When choosing a supplement, it is important to buy a formula that contains piperine, the major active component of black pepper, which has been shown to increase curcumin’s bioavailability by 2000 percent. A patented combination of curcumin and essential oils and a combination of curcumin and soy lecithin have also shown to increase its bioavailability.
Are curcumin supplements safe? Curcumin is generally safe when taken short-term. High doses may cause side effects in some people, namely gastrointestinal discomfort (nausea, bloating and diarrhea). The effects of taking curcumin for an extended period of time are unknown.
Can pregnant women and women who are breastfeeding take curcumin supplements? According to the American Pregnancy Association, curcumin may be associated with pregnancy risks if it is taken in large doses or concentrated forms. The amounts found in foods, however, are generally considered safe. Due to the lack of evidence about its safety in women who are breastfeeding, it should not be used unless recommended by a physician.
Can children take curcumin? The effects in children are not yet known. Therefore, supplementation is not recommended for children at this time.
Will curcumin interact with medication? Curcumin may make the effects of blood-thinning medications stronger, raising the risk of bleeding. Blood-thinners include warfarin (Coumadin), clopidogrel (Plavix) and aspirin, among others. It may interfere with the action of drugs that reduce stomach acid, increasing the production of stomach acid. Supplementation may also make the effects of drugs for diabetes stronger, increasing the risk of hypoglycemia (low blood sugar).
How should curcumin supplements be stored? Store them in their original container in a cool, dry location. And as you would any other medication/supplement, store them out of reach of children.
Curcumin is a polyphenolic compound derived from turmeric which studies show offers a wide spectrum of therapeutic effects, primarily due to its antioxidant and anti-inflammatory effects. The results of research reveal its potential to treat and prevent arthritis (namely rheumatoid arthritis and osteoarthritis), neurodegenerative diseases (such as Alzheimer’s disease), certain cancers and neuropsychiatric disorders.
There is also growing evidence that supplementation may play a protective role against cardiovascular disease, liver disease and gastrointestinal disorders.
Researchers stress the importance of performing further human studies to understand in full how this compound works and if there are any negative effects with long-term use.