Curcumin has been used for medicinal purposes for over four thousand years, but it has only recently come onto the radar of the average patient as a therapeutic supplement. This polyphenol, which is the active component in the spice turmeric (Curcuma longa), stands out among supplements because of its versatility. Over the last few decades, researchers have conducted both laboratory and clinical studies indicating that curcumin can offer health benefits to patients with a broad spectrum of diseases and disorders—ranging from the common cold to cancer—because it can play so many different roles in the body. The benefits of curcumin stem primarily from its anti-inflammatory and antioxidant activities, but it also has antimicrobial and protein regulatory properties that further expand its potential benefits as a therapy.
Despite these promising findings, it is important to note that curcumin is not a miracle compound. Specifically, there are concerns about the compound’s bioavailability, which could limit the usefulness of supplements in clinical settings. Therefore, when considering how curcumin might be integrated into a therapeutic strategy, it is important for patients to understand the limitations of curcumin and the innovative delivery systems that have been developed to overcome them.
Curcumin for Common Ailments: Antimicrobial and Anti-Inflammatory Properties
Curcumin has long been a staple of traditional medicine. Although its historical uses vary somewhat between cultures, the health conditions that it has been used to prevent and/or treat have certain things in common; most notably, many stem from either inflammation or infection, such as gastrointestinal conditions, viral infections, and even periodontal disease. These similarities have directed scientists’ research on curcumin, and the subsequent studies have borne out the anecdotal evidence. For instance, multiple comprehensive review studies highlight curcumin’s effectiveness as an antibacterial, antiviral, and antifungal agent, which can help explain why it has historically been used to treat respiratory symptoms, stave off the flu, and treat bacterial infections. Moreover, recent studies suggest that curcumin plays a modulatory role in the activation of key components of the immune system—including T cells, B cells, macrophages, neutrophils, natural killer cells, dendritic cells, and a wide range of cytokines—which suggests that it can directly modulate the functioning of the immune system.
The effects of curcumin on immune health are also facilitated by its role as an antioxidant and an anti-inflammatory agent. This can help explain the traditional use of curcumin for another common ailment: arthritis. Again, thousands of years of anecdotal evidence suggests that patients can benefit from supplementation, and the latest clinical research indicates the same. For instance, in a 2016 systematic review and meta-analysis published in the Journal of Medicinal Food, researchers combined the data from 8 randomized controlled trials—which together included over 800 patients—to analyze the efficacy of curcumin for treating arthritis patients. Based on the statistical significance of the results, the authors reported that a supplement of 1000 mg of curcumin per day is likely to have observable clinical results. Even though they also expressed concerns about the methodologies and the sample sizes of the studies they reviewed, it is clear that the early evidence tends to support the efficacy of curcumin for reducing arthritis inflammation.
Curcumin as a Therapeutic Option for Neurological Conditions
In addition to offering therapeutic benefits for common infections and inflammatory conditions, recent studies also suggest that curcumin may be an effective component of a prevention and/or treatment strategy for seemingly intractable neurological conditions that have stumped scientists for decades. Studies show that the compound may have benefits for patients with autism spectrum disorder, Parkinson’s disease, epilepsy, tardive dyskinesia, and Alzheimer’s disease, among others. Although the mechanisms through which it provides these benefits are not entirely clear, there is significant research to suggest that its effects stem from its anti-inflammatory activities within the brain.
One piece of evidence for this hypothesis comes from a 2015 study, in which a group of researchers from Punjab University in India explored how the anti-inflammatory properties of curcumin might provide benefits for patients with autism. In this study, the researchers treated their rat models of autism with either 50, 100, or 200 mg/kg of curcumin per day. Then, the rats were tested for behavioral paradigms of the disorder, including social problems, locomotor issues, anxiety, depression, spatial learning deficits, and repetitive behaviors. On the behavioral tests, the researchers noted statistically significant improvements, and their subsequent biochemical tests revealed a decline in the activity of metalloproteinases and their associated impacts on the inflammatory response.
Another study examining the potential of curcumin as a therapeutic for neurological disorders was published in the journal Metabolic Brain Disease in 2017. For this study, the researchers treated a rat model of Parkinson’s disease with 200 mg/kg of curcumin and examined the effects using a combination of electrophysiological and behavioral experiments. Their data indicated that supplementation could lead to significant improvements in motor impairments, so it may be beneficial for the treatment of Parkinson’s disease.
In both of these studies, researchers were hopeful about the future of curcumin as an effective supplement for preventing and treating neurological disorders. Although it will be necessary to verify these animal studies with more comprehensive clinical studies in the future, they strongly suggest that curcumin’s anti-inflammatory effects on the brain have the potential to provide benefits for patient populations that have long struggled to find effective therapeutics for neurological conditions.
Considering Curcumin as an Anti-Cancer Agent
In recent years, there have also been studies suggesting that curcumin may be able to help prevent cancer, slow its progression, or even help eliminate an existing tumor. The results of in vitro and in vivo studies have varied, but some of the most recent efforts to elucidate the mechanisms through which curcumin might act as an anti-cancer therapy have been particularly intriguing. Given the compound’s well-known antioxidant activities, it comes as no surprise that curcumin may help prevent cancer-causing DNA damage precipitated by harmful reactive oxygen species. However, there is also exciting new research to suggest that curcumin may be able to directly modulate the activities of proteins in key cancer pathways, including tumor suppressors and hormone receptors.
Among the most recent research supporting this possibility was a 2017 study that focused specifically on breast cancer. A group of researchers at Oakland University in Rochester, Michigan, conducted in vivo studies in cultured breast cancer cells to examine how curcumin treatment impacted levels of p53 (a well-known tumor suppressor protein) and estrogen receptor-alpha (a hormone receptor involved in breast cancer proliferation). Their subsequent protein analysis revealed significant decreases in the levels of both proteins, which further added to the evidence that curcumin’s protein regulatory properties may one day offer significant therapeutic benefits for cancer patients.
Recognizing the Limitations of Curcumin Supplements: The Question of Bioavailability
Because the majority of the research on curcumin’s health benefits has been conducted in the lab and clinical trials have remained small, there are still questions about whether or not the studies in cells and animals will be able to translate to human patients. This is particularly true because curcumin has an unusually low level of bioavailability—that is, when taken directly as an oral supplement, only a limited amount of the compound can be absorbed by the body. This is one of the major barriers to the use of curcumin as a supplement for treating any disease or disorder, but scientists have found ways to overcome this limitation.
In order to address the problem or bioavailability, researchers have developed innovative delivery systems that can increase the absorption rate of curcumin, ensuring that patients’ cells will be exposed to the same levels as the cells and the animals in the lab. Therefore in contrast to the mixed results of earlier studies, future research is more likely to reveal real-world benefits of curcumin for patients—whether the patient is simply trying to avoid getting the flu or whether they are looking to treat a highly debilitating condition like autism or breast cancer. Thanks to these new delivery systems, patients and practitioners now have the opportunity to explore how curcumin’s traditional benefits have truly been enhanced by the latest technology.
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