Turmeric (pronounced ter-muh-rihk) is a spice that has been used in cooking since 600 B.C. and is the root of a plant related to ginger. It has a bitter flavor and an intense yellow-orange color. It is very popular in Indian and Middle Eastern cooking and is used in curry mixtures. It is also the ingredient that gives American style mustard its bright yellow color.
In addition to its use in cooking, turmeric, or one of its components are frequently marketed as a dietary supplement. Turmeric or curcumin supplements have also been promoted for a host of other health issues. Some of these claims have merit, while others do not.
Turmeric contains several curcuminoid compounds, such as curcumin. It is these compounds that give turmeric its distinctive yellow color as well as its antioxidant and anti-inflammatory properties. The anti-inflammatory properties make turmeric a popular ingredient in many nutritional supplements to reduce pain and inflammation. The mechanism for the anti-inflammatory properties may be due to the blocking of cyclooxygenase-2. In humans, cyclooxygenases help convert arachidonic acid to prostaglandin H2 and then prostacyclin, which results in inflammation.
Turmeric has been studied for its potential gastrointestinal benefits and has been found in some research to relieve indigestion. Curcumin may help people with ulcerative colitis when used in conjunction with medication.
Curcumin may improve symptoms of rheumatoid arthritis similar to non-steroidal anti-inflammatory drugs. Numerous studies have examined the impact on joint swelling and stiffness with mixed results. Some studies found a significant reduction of joint pain and inflammation in people with rheumatoid arthritis, while others found no improvement. Studies on use of curcumin for osteoarthritis of the knee have been equally mixed, with some showing improvement and others only showing a slight benefit, especially in those people already taking an anti-inflammatory drug.
Curcumin has shown potential for improvement in memory. But again, the results are mixed with some studies showing improvement in cognition and mental fatigue and others no improvement. One study did find improvement in short-term memory scores in individuals aged 60 and over who consumed ¼ teaspoon of turmeric powder daily with breakfast.
Both laboratory and animal studies have shown that curcumin inhibits some processes in the brain associated with the development of Alzheimer’s disease. These processes include inflammation, oxidative stress, and the formation of amyloid-beta proteins (brain plaque associated with Alzheimer’s).
Curcumin may reduce increases in blood sugar and insulin after eating, as well improve insulin resistance in healthy people. However, curcumin supplementation in people who already have Type II diabetes showed only slight to no benefit when looking at hemoglobin A1c tests (a test that shows the average level of glucose in your blood for the previous three months).
Turmeric and curcumin are best absorbed when consumed with food containing some fat to aid in absorption. In dietary supplements, the daily amount ranges from 500 mg to 2000 mg, most of which is typically curcumin or curcuminoid compounds. Turmeric powder is only about 3% curcuminoids. One teaspoon of turmeric powder (about 5,000 mg) only contains about 150 mg of curcuminoids.
Caution With Turmeric:
Turmeric and curcumin when taken as a supplement or when used in cooking is generally safe, even at the higher doses found in supplements. However, negative side effects are possible, especially when taken in higher doses found in some supplements. The negative side effects can also occur due to other ingredients added to supplements to aid in absorption of curcumin.
Turmeric can stimulate the gallbladder to contract. People with gallstones or gallbladder disease should use caution in taking high dose supplements.
Although curcumin has been found in some research studies to have a protective effect on the liver, adverse effects on the liver and elevated liver enzymes have been reported, especially with higher doses.
Turmeric contains oxalate, which can bind with calcium to form calcium oxalate kidney stones. People who are prone to developing calcium oxalate kidney stones may need to limit intake of oxalate.
Some research has shown that curcumin can lower blood sugar levels. Therefore, curcumin can enhance the effectiveness of blood sugar lowering medication, resulting in hypoglycemia. People who are taking medications to lower blood sugar should use caution in supplementing with curcumin.
Summing It Up:
Turmeric has been used for centuries in cooking. More recently, turmeric has gained attention as a supplement ingredient such as those often advertised for pain relief. When evaluating research related to turmeric, note that some research studies used turmeric powder, while others used curcumin or other ingredients in turmeric. This variation in research methods used can make it difficult to evaluate and compare the results between studies. In promoting turmeric containing supplements, claims are made for a host of health issues. While turmeric supplements are generally safe, there can be negative side effects. It is best to check with your physician for possible interaction with other medications, or if you experience any unusual symptoms while taking turmeric. Turmeric has been promoted for use in numerous health issues, with the most prominent related to the anti-inflammatory response of curcumin. Regardless of whether you choose to use a commercial supplement containing turmeric, you can opt to include ground turmeric in your home spice collection. Turmeric does have antioxidant and anti-inflammatory properties and can enhance the color and flavor of food.
Cooperman, T. (2021). Turmeric and Curcumin Supplements and Spices Review. Consumer Lab. Retrieved from: https://www.consumerlab.com
Dansinger, M. (2020). Hemoglobin A1c Test for Diabetes. WebMD. Retrieved from: https://www.webmd.com
Herbst, S. T. (2001). Food Lover’s Companion, 3rd ed. New York: Barron’s Educational Series.
Wikipedia (2021). Prostaglandid-endoperoxide synthase 2. Retrieved from: https://en.wikipedia.org