Turmeric is a popular Eastern spice grown throughout India, Asia, and Central America. It has been historically used in Ayurveda medicine for many chronic conditions, such as rheumatism, pain, and fatigue. Turmeric contains an active group of polyphenolic compounds called curcuminoids, of which curcumin is the most well studied (“Turmeric,”).
Curcumin is thought to have potential benefits by reducing inflammation, which is the body’s response to infection or injury and is necessary to combat disease. The Nuclear Factor-kappaB (NF-kB) pathway serves as a pivotal mediator in the inflammatory response and is usually deregulated in chronic conditions such as atherosclerosis and diabetes. The result is prolonged inflammation that increases tissue damage, however initial studies have explored how curcumin can mitigate this problem (Liu, Zhang, Joo, & Sun, 2017).
A study on human biliary cancer cells found that curcumin mediated the effects of the NF-kB pathway and induced apoptosis, or cell death, thereby halting the formation of new cancer cells (Prakobwong et al., 2011). Curcumin affects these processes via 1) the activation of caspase-3, -8, and -9, which are the enzymes involved in programmed cell death, and by 2) inhibiting IkB Kinase (IKK) activation, a key complex necessary for activation of the NF-kB pathway (Prakobwong et al., 2011). If this is the case, curcumin could serve as a potent mediator in diseases where chronic inflammation is prevalent, such as cancer.
A systematic review exploring the effects of curcumin on diabetes found it reduces the NF-kB inflammatory pathway, as mentioned above. Curcumin also helps elevate plasma insulin, which is the hormone that decreases blood glucose. Additionally, when paired with Vitamin C and yogurt, it has been found to reduce HgbA1C in rat models, a 3 month indicator of blood sugar management (Zhang, Fu, Gao, & Liu, 2013). Similarly, data has shown benefits of curcumin in regard to obesity, which is a proinflammatory state (He et al., 2015).
As for the health and safety of consumption, curcumin is a generally recognized as safe compound by the Food and Drug Administration. The Joint United Nations and World Health Organization Expert Committee on Food Additives (JECFA) and European Food Safety Authority (EFSA) reports the Allowable Daily Intake (ADI) value of curcumin is 0–3 mg/kg body weight (Kocaadam & Sanlier, 2017). However, negative side effects have been reported in those consuming higher quantities. In a dose-response study with subjects receiving 500–12,000 mg, diarrhea, headache, rash, and yellow stool were reported. While this varies among individuals, a generally healthy individual can consume between 4-10 g of turmeric powder in accordance with the JECFA and EFSA’s ADI without negative side effects (Kocaadam & Sanlier, 2017). Overall, it seems that a dose as low as 80 mg/day of curcumin can provide health benefits (Hewlings & Kalman, 2017). Although gastrointestinal upset has been seen among individuals in some studies, further research is needed to determine the full extent of benefits, bioavailability, and dose-response of turmeric. As with any trending topic in the nutrition field, it is important to consider one’s diet rather than focusing on a single nutrient when trying to maintain a healthy lifestyle.
References
He, Y., Yue, Y., Zheng, X., Zhang, K., Chen, S., & Du, Z. (2015). Curcuminin flammation, and chronic diseases: how are they linked? Molecules, 20(5), 9183-9213. doi:10.3390/molecules20059183
Hewlings, S. J., & Kalman, D. S. (2017). Curcumin: A Review of Its’ Effects on Human Health. Foods, 6(10). doi:10.3390/foods6100092
Kocaadam, B., & Sanlier, N. (2017). Curcumin, an active component of turmeric (Curcuma longa), and its effects on health. Crit Rev Food Sci Nutr, 57(13), 2889-2895. doi:10.1080/10408398.2015.1077195
Liu, T., Zhang, L., Joo, D., & Sun, S. C. (2017). NF-kappaB signaling in inflammation. Signal Transduct Target Ther, 2. doi:10.1038/sigtrans.2017.23
Prakobwong, S., Gupta, S. C., Kim, J. H., Sung, B., Pinlaor, P., Hiraku, Y., . . . Aggarwal, B. B. (2011). Curcumin suppresses proliferation and induces apoptosis in human biliary cancer cells through modulation of multiple cell signaling pathways. Carcinogenesis, 32(9), 1372-1380. doi:10.1093/carcin/bgr032
Turmeric. (November 27, 2018). Retrieved from https://nccih.nih.gov/health/turmeric/ataglance.htm Zhang, D. W., Fu, M., Gao, S. H., & Liu, J. L. (2013). Curcumin and diabetes: a systematic review. Evid Based Complement Alternat Med, 2013, 636053. doi:10.1155/2013/636053
