Turmeric (Curcuma longa L) root has been consumed as part of the diet in Indian culture for around 4000 years. It gives Indian cuisine its characteristic golden color and distinctive flavor. In 1280 Marco Polo described turmeric and marveled at a vegetable that exhibited qualities very similar to that of saffron. It also has a long history of medicinal use throughout South Asia, and was mentioned in Susruta’s Ayurvedic Compendium, dating back to 250 BC. The use of turmeric as a medicinal has expanded dramatically in recent decades and current production globally is well over 1 million tons annually.

Therapeutic turmeric is now usually available as an extract containing 95% polyphenolic curcuminoids, the active components in turmeric responsible for its health attributes. The most important and biologically active curcuminoid is curcumin. The first clinical trial on curcumin was reported in the Lancet in 1937. Since that time there have been more than 9000 publications on curcumin and well over 100 different clinical trials. Curcumin is recognized as being nontoxic and displays a number of therapeutic properties including antioxidant, analgesic, anti-inflammatory, antiseptic, anticarcinogenic, chemo-preventative, chemotherapeutic, anti-tumor, antiviral, antibacterial, antifungal and antiplatelet aggregation. The two main therapeutic benefits arise from its action as an anti-inflammatory and as an antioxidant.

Much of the clinical research on curcumin is associated with its potential role in reducing the effects of age-associated diseases. A recent review article summarized the research related to benefits in a wide array of age-related chronic disorders including improvements in lipid profiles, effects in ocular diseases and other eye disorders, and as an anti-diabetic. In another study, healthy middle-aged and older adults were the subjects in a randomized, placebo-controlled 12-week study that concluded that curcumin supplementation improves resistance artery endothelial function by increasing vascular nitric oxide bioavailability and reducing oxidative stress. These results point to benefits in diminishing the effects of age-related large artery stiffness.

Curcumin can suppress both acute and chronic inflammation, which explains its benefits in mediating multiple health challenges. For example, neuroinflammation is present in many neurodegenerative disorders, such as Alzheimer’s disease, stroke, traumatic brain injury and age-related CNS disorders. One of the common treatments involves the use of cytokine suppressive anti-inflammatory drugs (CSAIDS). Curcumin is a promising CSAID, as it has been shown to modulate the activity of several transcription factors, such as STAT, NF-κB, and AP-1. In addition, curcumin seems to have other benefits to the central nervous system, including its ability to bind to amyloid proteins.

Curcumin can also help control the inflammation arising from radiotherapy and chemotherapy by targeting inflammatory mediators such as cyclooxygenase-2, inducible nitric oxide synthase and nuclear factor κB (NF-κB), resulting in a reduced release of proinflammatory and profibrotic cytokines and suppressing chronic production of free radicals, leading to the amelioration of tissue toxicity. It also exhibits cytoprotective effects in normal tissues, making it a worthy adjunct in cancer therapy.

The benefits of curcumin in reducing inflammation and oxidative stress extends to healthy individuals. One study investigated the effects of curcumin in ameliorating the systemic low-grade inflammation and oxidative stress linked to obesity in adolescent girls. This study demonstrated the positive effects of curcumin supplementation in ameliorating the pro-inflammatory activity of the cytokine, Interleukin-6 and reducing levels of the inflammatory biomarker, C-reactive protein (CRP). Total antioxidant capacity (TAC) was also improved.

Healthy individuals were also the subjects of a recent RCT study demonstrating curcumin’s benefits in reducing the muscle-damaging effects of an unaccustomed exercise. Though the results were not clinically significant, they did show trends toward a positive outcome, especially in the higher dose of enhanced bioavailability curcumin ingredient (CurcuWIN®).

The popularity of turmeric and curcumin has not been without some challenges. Clinical and supplemental use has been hampered by poor oral bioavailability and rapid metabolism. This has led to the growth of novel processing methods such as nanotechnology or the use of adjuvants to slow down metabolism and elimination from the body. These unique processing methods show promise in enhancing solubility, extending the residence in the plasma, improving the pharmacokinetic profile and increasing cellular uptake. Many of the more recent studies have been conducted using these novel trademarked forms that have been shown to drastically improve tissue of levels of curcumin metabolites, such as free curcumin compared to 95% curcumin. Some of these curcumin ingredients such as BIOCURC® can be made using natural components, such as coconut oil, to greatly enhance bioavailability.

Another challenge in studying and marketing curcumin has been the growth of synthetic and adulterated versions of the natural ingredient derived from the turmeric (Curcuma longa) rhizome. As with any ingredient experiencing impressive market growth, there are those who will attempt to profit from low quality adulterated ingredients. Fortunately, the identity of true, natural curcumin can be substantiated by such methods as Carbon-14 dating.

As the popularity of curcumin continues to grow, so will the research into other areas of health benefits and disease mediation. Not only can we feel good about enjoying our turmeric-filled Indian dishes, we can supplement with an ingredient that is truly one for which everyone can benefit.

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