Updated on February 2, 2023
- Although turmeric has been used medicinally for thousands of years, researchers have only recently begun to explore its potential to address gastrointestinal disorders.
- Curcumin, a turmeric-derived compound, supports the body’s natural inflammatory response and promotes the optimal functioning of antioxidants, but clinical evidence is inconsistent due to bioavailability issues.
- Tetrahydrocurcumin supplements offer superior therapeutic efficacy due to their bioavailability.
For thousands of years, the spice turmeric has been renowned for both its culinary uses and for a multitude of potential health benefits, ranging from decongestion to wound healing to addressing chicken pox symptoms. In recent years, as the scientific community has increasingly recognized the therapeutic potential of turmeric, it has led to the development of sophisticated nutritional supplements formulated with curcumin, the active metabolite in turmeric. By combining advanced medical technologies with traditional medicine to create more effective turmeric supplements, new opportunities are opening up for managing a wide range of health conditions.
When it comes to gastrointestinal disorders, biochemical research indicates the benefits of curcumin derive from properties that enhance the body’s natural inflammatory response and promote the optimal functioning of antioxidants.* However, due to the naturally low bioavailability of curcumin, the clinical evidence is still mixed. The most recent research suggests that a relatively new turmeric-based supplement—tetrahydrocurcumin—is effective for addressing gastrointestinal symptoms, particularly when delivered in a highly bioavailable form.* There is already one noted tetrahydrocurcumin therapy on the market and with its promise, we expect to see more over time.
The Positive Effects of Curcumin in Turmeric Supplements
Inflammation in the gastrointestinal tract is associated with many of the functional bowel problems that commonly characterize conditions like ulcerative colitis, irritable bowel syndrome (IBS), and even autism spectrum disorder (ASD). At the biochemical level, the effectiveness of curcumin for helping to maintain a normal inflammatory response in the GI tract is largely the result of its ability to interact with multiple molecular targets and thereby modulate a wide range of inflammation-related signaling pathways.* Specifically, curcumin can benefit the following processes:
- Inhibition of inflammatory cytokines. Cytokines are small proteins released by cells that function in innate and adaptive immune systems. They play a key role in cell signaling, acting as messengers to other parts of the cell to mount a full-scale immune response. Thus, the natural activity of curcumin down-regulates cytokine activity.*
- Down-regulation of two types of MAP and JAK kinases. Proteins in the kinase family play a key role in the mounting of the immune response, binding to transmembrane proteins that initiate changes in the cells that promote inflammation. By reducing the activities of these proteins, curcumin helps maintain a normal inflammatory response in the GI tract.*
- Down-regulation of three enzymes that promote inflammation (COX-2, lipoxygenase, and inducible nitric oxide synthase). COX-2, a common target for over-the-counter and prescription NSAIDs, can not only address inflammation in the GI tract but can also serve as a useful alternative to drugs that alter the body’s natural inflammatory response and threaten long-term GI health.
In recent years, researchers seeking to understand the mechanistic intricacies of inflammatory bowel disease have identified connections between NF-kappa-B inflammatory cytokines and a specific kinase-associated signaling pathway—and curcumin plays a beneficial role in both pathways. As a result, more researchers and clinicians are suggesting turmeric supplements as possible support options for patients with bowel inflammation.*
Similarly, recent biochemical research highlights the molecular mechanisms through which curcumin acts as an antioxidant.* At the most basic level, reactive oxygen species (ROS) can be generated by various aspects of the immune response, so curcumin can act as an antioxidant.* In addition, curcumin has been shown to beneficially regulate the expression of Nrf2, a protein that turns certain genes on to produce proteins.* These genes code for enzymes that degrade ROS or stop them from being produced unnecessarily. Therefore, when Nrf2 activity is high, the levels of ROS-fighting proteins are also high. In this way, the activity of curcumin indirectly impacts ROS.*
Enhancing the Effects of Curcumin
Although there is solid in vitro evidence of biochemistry behind the activities of curcumin, the clinical results are less convincing. For instance, in a 2017 review of clinical studies in which curcumin was used to address functional and gastrointestinal disorders, the results were promising, but not definitive. The authors noted a number of studies indicating potential efficacy:
- A randomized, blinded (but not placebo-controlled) study in which 207 IBS patients were administered curcumin for 8 weeks showed definite improvements.*
- Two randomized, double-blinded, placebo-controlled studies in which curcumin was shown to be effective.
- Two small-scale, open studies in which both pediatric and adult patients reported “marginal benefits” after taking a curcumin supplement.
However, other studies have failed to establish the statistically significant therapeutic effects one would expect based on in vitro findings.
One of the reasons curcumin has proven to be more effective in the lab than in the clinic is its natural low bioavailability, which has long been recognized by researchers. In a 1978 study, researchers found that in rats that took curcumin supplements (1g/kg of body weight), 75 percent was excreted in the feces. More recently, a 2001 study showed that significant quantities of curcumin were also present in the fecal samples of a group of 15 patients who were taking between 36 mg and 180 mg of curcumin per day. This indicates that a considerable proportion of the curcumin the patients took in was being excreted without being absorbed.
Due to these decades-old concerns about bioavailability, researchers are examining the potential efficacy of tetrahyrdocurcumin, an active metabolite of curcumin that can be much more readily metabolized when taken in supplement form than the curcumin in traditional turmeric supplements.* In a 2014 paper out of the Department of Experimental Therapeutics at UT Austin, the authors highlighted both in vitro and animal studies demonstrating that the efficacy of tetrahydrocurcumin as an antioxidant is significantly higher than that of curcumin.* Not only does this metabolite show improved efficacy for quenching free radicals, but it also induces key antioxidant enzymes, including GSH peroxidase, glutathione-S-transferase, quinone reductase, and NADPH.*
It is important to note that the differences in the activity of curcumin and tetrahydrocurcumin are not only derived from their different bioavailability levels but also because they have different molecular targets. While it is true that tetrahydrocurcumin does not bind to some of the targets involved in the body’s natural inflammatory response, it also limits some of the mild pro-inflammatory activities of curcumin, which might contribute to its effectiveness on the clinical level.*
There is also preliminary evidence suggesting that certain delivery systems can better support the bioavailability of different types of curcumin supplements, including both curcumin and tetrahydrocurcumin. In one randomized, double-blind study, researchers at the University of Tampa found that serum levels of curcumin were 45.9 times higher in patients who took a formulation of curcumin that included a hydrophilic carrier, cellulosic derivatives, and natural antioxidants, as compared to those who took an unformulated supplement. In the same study, researchers also reported a 7.9-fold rise in absorption of curcumin in patients who took a phytosome formulation and a 1.3-fold rise in those who took a formulation with volatile oils of turmeric rhizome. These results indicate that the delivery system can make an important difference in the bioavailability of curcumin.
Choices for Clinicians and Patients: Yes or No to Turmeric Supplements?
Based on strong biochemical evidence, recommendations for turmeric supplements are becoming increasingly common. Although more research is needed to confirm clinical efficacy on a broad scale, these nutritional supplements present intriguing possibilities for clinicians and patients who want to look beyond conventional gastrointestinal therapies for more additional symptom relief. For those who wish to integrate curcumin or tetrahydrocurcumin into their therapies, TetraCumin from Tesseract Medical Research could be a beneficial place to start.
The power of Tesseract supplements lies in enhancing palatability, maximizing bioavailability and absorption, and micro-dosing of multiple nutrients in a single, highly effective capsule. Visit our website for more information about how Tesseract’s products can help support your gastrointestinal health.*
Works Cited
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Hilsden RJ, Verhoef MJ, Rasmussen H, Porcino A, DeBruyn JC. 2011. Inflammatory Bowel Diseases. 17(2):655-62.
Jager R, Lowery RP, Calvanese AV, Joy JM, Purpura M, Wilson JM. 2014. Nutrition Journal. 13:11.
Soetikno V, Sari FR, Lakshmanan AP, Armugam S, Harima M, Suzuki K, Kawachi H, Watanabe K. 2013. Molecular Nutrition & Food Research. 57(9):1649-59.
Yuksel I. 2017. Medical Principles and Practice. 26(4): 397.