In the Spotlight: Turmeric

What is turmeric?

Turmeric (Curcuma longa), the bright yellow spice often used in Indian cuisine, has recently gained quite a reputation as a superfood, primarily due to its anti-inflammatory and antioxidant properties. It is extensively used as a spice, food preservative and coloring material in India, China and South East Asia. It has also been used in traditional medicine as a household remedy for various diseases, including indigestion, throat infection, anorexia, cough and others [1].

It is common for people to confuse turmeric and curcumin, since the two words are often used interchangeably. However, turmeric is the plant itself, while curcumin is the yellow pigment and is considered the main active ingredient in turmeric. Below we will review some of the current research on the potential therapeutic effects of turmeric and curcumin.

Antioxidant Effects of Turmeric

Damage caused by oxidative stress is considered to be one of the primary mechanisms involved in aging as well as many diseases, such as Alzheimer’s disease, Parkinson’s disease and cancer [2]. The primary reason why antioxidants are so important is because they are able to prevent oxidative damage. Antioxidants are found in abundance in green leafy vegetables, fruits, herbs and spices.

Recent research has shown that turmeric may have the ability to enhance the activity of our body’s own antioxidant enzymes [3, 4, 5]. In addition, curcumin’s chemical structure allows it to act as a direct antioxidant by reducing oxidative stress by itself [6, 7]. However, the issue is that curcumin is not easily absorbed into the bloodstream.

By consuming curcumin with the addition of ground black pepper, the absorption of curcumin is enhanced significantly [8, 9]. Ground black pepper contains the molecule piperine, which inhibits the process by which the liver blocks the absorption of curcumin. Additionally, while isolated curcumin is not easily absorbed into the bloodstream, turmeric oil present in whole turmeric significantly enhances the bioavailability (ability to be absorbed and utilized by the body) of curcumin in humans [10, 11]. Thus, curcumin, if consumed correctly, can actually be absorbed into the bloodstream and can potentially act as a direct and indirect antioxidant.

Anti-inflammatory Effects of Turmeric

Inflammation is crucial for our body on the short term since it is one of the primary ways our body deals with various sources of distress such as toxins, bacteria and trauma. However, things change when inflammation is chronic, because long term low levels of inflammation can play a major role in the development of various diseases, such as cancer, Alzheimer’s disease and heart disease to name a few.

It is known that herbs and spices have some of the greatest antioxidant and anti-inflammatory activities. In fact research in human subjects shows that intake of spices and herbs, including turmeric, resulted in significant anti-inflammatory and antioxidant effects, as well as an improved ability to downregulate the inflammatory response when exposed to stressors. Incredibly, these results are seen in dosages similar to the amount of a spice or herb that one might use on a day to day basis while cooking (in the case of turmeric, 1/10 of a teaspoon daily) [12].

Anti-Alzheimer’s Disease Effects of Turmeric

Turmeric and curcumin have been increasingly studied for their role in preventing and reversing Alzheimer’s disease and supporting cognitive health. Naturally, the anti-inflammatory and antioxidant reach of turmeric do much in treating the root cause of inflammatory Alzheimer’s disease [13,14]. By doing so, metabolic homeostasis is achieved often resulting in reduction or reversal of memory loss and other symptoms.

This makes turmeric a remarkable treatment modality for Alzheimer's disease; however even more impressively, at certain dosages, curcumin has even been shown to help reduce the amount of beta-amyloid plaques, one of the characteristic markers of Alzheimer’s disease. Curcumin is able to cross the blood brain barrier, bind onto amyloid plaque aggregates in the brain, and clear them away through a process called phagocytosis [15]. Perhaps for this reason, curcumin supplementation is often listed on the ReCODE Reports for clients following the Bredesen Protocol.

Anti-Cancer Effects of Turmeric

As we all know, cancer is a disease characterized by uncontrollable cell growth. While there are many different types of cancer, there is some research that shows that turmeric and curcumin may be able to prevent and suppress various types of cancer.

Researchers have shown that individuals at high risk for colon cancer could slow and even reverse the progression of their disease by taking curcumin supplements. Supplementation with curcumin has in many studies resulted in significant drop in the number and size of polyps, small clumps of cells in the colon, which over time may develop into cancer, or aberrant crypt foci, which are the precursors to polyps [16, 18]. Other studies indicate that turmeric extract slows the progression of colon cancer [17].

Beyond colon cancer, the use of curcumin has also been shown to help in the treatment of other cancerous lesions, specifically in the mouth, skin, cervix and bladder [19]. There is also research indicating possible beneficial effects of turmeric and curcumin in other types of cancer, such as prostate [20] and pancreatic cancer [21, 22]. It is important to note that while the effects of curcumin extracts on cancer are promising, current research shows that whole ground turmeric is more potent than curcumin [23], which suggests that there are other substances in turmeric beyond curcumin that contribute to the anti-cancer activities of turmeric [24].

Since supplementation with turmeric and curcumin extracts does not produce any significant side effects, especially when compared to the side effects produced by drugs and chemotherapy traditionally used in cancer treatment, turmeric could be used as an added measure against cancer, besides other dietary and lifestyle interventions.

How to Consume Turmeric

Now that you’ve read all about the tremendous benefits of turmeric, you’re probably eager to start using it! But how should turmeric be consumed? As mentioned previously, the oils found in whole turmeric improve the absorption of curcumin and pipperine found in black pepper also significantly increases the bioavailability of curcumin [8-11]. So the best way to implement turmeric in a recipe is to use whole ground turmeric with the addition of black pepper (which is common in most curries anyways).

But how much turmeric is enough? Most cultures that use ground turmeric in their cuisine the use around one teaspoon [25]. The Amos Institute recommends shaving fresh turmeric into salads, boiling turmeric with ginger and lemon to make a tonic, or grating turmeric into a mug full of steamed coconut milk and cinnamon for a warming Golden Milk.

If you choose to supplement with curcumin, it’s important that you check with a health care practitioner, as you should before starting any new supplement, especially if you are pregnant or breastfeeding. In general, from a safety standpoint, whole turmeric is generally preferred over curcumin supplementation [26].

What's the Takeaway?

There is a promising amount of research that shows that whole turmeric as well as curcumin supplements provide exceptional health benefits. Of course, more research is required in order to compare the specific effects of turmeric and isolated curcumin. Turmeric contains over 300 other substances other than curcumin [24] and research has shown that while curcumin accounts for the majority of the therapeutic effects of turmeric, whole turmeric is more beneficial when compared to curcumin supplements [23, 31]. Researchers hypothesise that other substances in turmeric are also beneficial and may assist in the absorption of curcumin [32].

Additionally, consumption of ground turmeric on a day to day basis does not appear to have any significant side effects, especially compared to the traditional drug treatments used for various diseases. You should start implementing whole turmeric into your day to day cooking in order to gain these outstanding benefits!

References

[1] Ishita C, Biswas K, Bandyopadhyay U, Banerjee R. Current Science. 87th ed. Indian Academy of Sciences; 2004:44–53.

[2] Uttara B, Singh A, Zamboni P, Mahajan R. Oxidative Stress and Neurodegenerative Diseases: A Review of Upstream and Downstream Antioxidant Therapeutic Options. Current Neuropharmacology. 2009;7(1):65-74. doi:10.2174/157015909787602823.

[3] Agarwal R, Goel S, Behari J. Detoxification and antioxidant effects of curcumin in rats experimentally exposed to mercury. Journal of Applied Toxicology. 2010;30(5):457-468. doi:10.1002/jat.1517.

[4] Biswas S, McClure D, Jimenez L, Megson I, Rahman I. Curcumin Induces Glutathione Biosynthesis and Inhibits NF-κB Activation and Interleukin-8 Release in Alveolar Epithelial Cells: Mechanism of Free Radical Scavenging Activity. Antioxidants & Redox Signaling. 2005;7(1-2):32-41. doi:10.1089/ars.2005.7.32.

[5] Bulmuş F, Sakin F, Türk G, Sönmez M, Servi K. Protective effects of curcumin on antioxidant status, body weight gain, and reproductive parameters in male rats exposed to subchronic 2,3,7,8-tetrachlorodibenzo-p-dioxin. Toxicological & Environmental Chemistry. 2013;95(6):1019-1029. doi:10.1080/02772248.2013.829061.

[6] Menon V, Sudheer A. Antioxidant and anti-inflammatory properties of curcumin. Advances In Experimental Medicine and Biology. 2007;595:105-125. doi:10.1007/978-0-387-46401-5_3.

[7] Barclay L, Vinqvist M, Mukai K et al. On the Antioxidant Mechanism of Curcumin:  Classical Methods Are Needed To Determine Antioxidant Mechanism and Activity. Organic Letters. 2000;2(18):2841-2843. doi:10.1021/ol000173t.

[8] C. K. Atal, R. K. Dubey, J. Singh. Biochemical basis of enhanced drug bioavailability by piperine: Evidence that piperine is a potent inhibitor of drug metabolism. J. Pharmacol. Exp. Ther. 1985 232(1):258 - 262.

[9] G. Shoba, D. Joy, T. Joseph, M. Majeed, R. Rajendran, P. S. Srinivas. Influence of piperine on the pharmacokinetics of curcumin in animals and human volunteers. Planta Med. 1998 64(4):353 - 356.

[10] P. Anand, A. B. Kunnumakkara, R. A. Newman, B. B. Aggarwal. Bioavailability of curcumin: Problems and promises. Mol. Pharm. 2007 4(6):807 - 818.

[11] Jäger R, Lowery R, Calvanese A, Joy J, Purpura M, Wilson J. Comparative absorption of curcumin formulations. Nutrition Journal. 2014;13(1). doi:10.1186/1475-2891-13-11.

[12] S. S. Percival, J. P. V. Heuvel, C. J. Nieves, C. Montero, A. J. Migliaccio, J. Meadors. Bioavailability of herbs and spices in humans as determined by ex vivo inflammatory suppression and DNA strand breaks. J Am Coll Nutr. 2012 31(4):288 - 294.

[13] T Ng, P Chiam, T Lee, H Chua, L Lim, E Kua. Curry consumption and cognitive function in the elderly. Am J Epidemiol. 2006 Nov 1;164(9):898-906.

[14] A Monroy, G J Lithgow, S Alavez. Review Article Curcumin and Neurodegenerative Diseases. Biofactors. 2013 Jan-Feb;39(1):122-32.

[15] Mishra, S., & Palanivelu, K. (2008). The effect of curcumin (turmeric) on Alzheimer’s disease: An overview. Annals of Indian Academy of Neurology, 11(1), 13–19.

[16] M Cruz-Correa, D A Shoskes, P Sanchez, R Zhao, L M Hylind, S D Wexner, F M Giardiello. Combination treatment with curcumin and quercetin of adenomas in familial adenomatous polyposis. Clin Gastroenterol Hepatol 2006 4(8):1035 – 1038

[17] R A Sharma, H R McLelland, K A Hill, C R Ireson, S A Euden, M M Manson, M Pirmohamed, L J Marnett, A J Gescher, W P Steward. Pharmacodynamic and pharmacokinetic study of oral Curcuma extract in patients with colorectal cancer. Clin Cancer Res 2001 7(7):1894 – 1900.

[18] R E Carroll, R V Benya, D K Turgeon, S Vareed, M Neuman, L Rodriguez, M Kakarala, P M Carpenter, C McLaren, F L Meyskens. Phase IIa clinical trial of curcumin for the prevention of colorectal neoplasia. Cancer Prev Res 2011 4(3):354 – 364.

[19] Cheng AL1, Hsu CH, Lin JK, Hsu MM, Ho YF, Shen TS, Ko JY, Lin JT, Lin BR, Ming-Shiang W, Yu HS, Jee SH, Chen GS, Chen TM, Chen CA, Lai MK, Pu YS, Pan MH, Wang YJ, Tsai CC, Hsieh CY. Phase I clinical trial of curcumin, a chemopreventive agent, in patients with high-risk or pre-malignant lesions. Anticancer Res. 2001 Jul-Aug;21(4B):2895-900.

[20] Freedland SJ, Carducci M, Kroeger N, Partin A, Rao JY, Jin Y, Kerkoutian S, Wu H, Li Y, Creel P, Mundy K, Gurganus R, Fedor H, King SA, Zhang Y, Heber D, Pantuck AJ. A double-blind, randomized, neoadjuvant study of the tissue effects of POMx pills in men with prostate cancer before radical prostatectomy. Cancer Prev Res (Phila). 2013 Oct;6(10):1120-7.

[21] N Dhillon, B B Aggarwal, R A Newman, R A Wolff, A B Kunnumakkara, J L Abbruzzese, C S Ng, V Badmaev, R Kurzrock. Phase II trial of curcumin in patients with advanced pancreatic cancer. Clin Cancer Res. 2008 Jul 15;14(14):4491-9.

[22] M Kanai, Y Otsuka, K Otsuka, M Sato, T Nishimura, Y Mori, M Kawaguchi, E Hatano, Y Kodama, S Matsumoto, Y Murakami, A Imaizumi, T Chiba, J Nishihira, H Shibata. A phase I study investigating the safety and pharmacokinetics of highly bioavailable curcumin (Theracurmin) in cancer patients. Cancer Chemother Pharmacol. 2013 Jun;71(6):1521-30.

[23] J H Kim, S C Gupta, B Park, V R Yadav, B B Aggarwal. Turmeric (Curcuma longa) inhibits inflammatory nuclear factor (NF)-κB and NF-κB-regulated gene products and induces death receptors leading to suppressed proliferation, induced chemosensitization, and suppressed osteoclastogenesis. Mol Nutr Food Res. 2012 Mar;56(3):454-65.

[24] B B Aggarwal, W Yuan, S Li, S C Gupta. Curcumin-free turmeric exhibits anti-inflammatory and anticancer activities: Identification of novel components of turmeric. Mol Nutr Food Res. 2013 Sep;57(9):1529-42.

[25] S. Bengmark, M. D. Mesa, A. Gil. Plant-derived health: The effects of turmeric and curcuminoids. Nutr Hosp. 2009 24(3):273 - 281.

[26] G. N. Asher, K. Spelman. Clinical utility of curcumin extract. Altern Ther Health Med. 2013 19(2):20 - 22.

[28] R. A. DiSilvestro, E. Joseph, S. Zhao, J. Bomser. Diverse effects of a low dose supplement of lipidated curcumin in healthy middle aged people. Nutr J. 2012 11:79.

[31] T. Ahmed, A.-H. Gilani. Therapeutic Potential of Turmeric in Alzheimer's Disease: Curcumin or Curcuminoids? Phytother Res. 2013.

[32] S C Gupta, B Sung, J H Kim, S Prasad, S Li, B B Aggarwal. Multitargeting by turmeric, the golden spice: From kitchen to clinic. Mol Nutr Food Res. 2013 Sep;57(9):1510-28.