What is Curcumin? Benefits, Dosage, and Risks
Turmeric, and its most potent phytochemical curcumin, have been a food and medicinal staple for thousands of years. Modern curcumin extracts are up to 2,000% times more bioavailable, delivering a wide range of therapeutic health benefits. Relief from inflammation, arthritis, autoimmune conditions, and healthier aging are just a few of the evidence-based benefits of supplementing with this potent plant compound.
Curcumin is a plant chemical found in turmeric, a spice common to traditional Indian cooking as well as Ayurvedic and Chinese Medicine practices. Specifically, curcumin belongs to a special subset of plant chemicals called polyphenols. It is from this class of potent phytochemicals that berries, herbs, and roots (like turmeric) derive their medicinal properties.
For thousands of years, Asian cultures have consumed curcumin in the form of turmeric. Today, modern science has isolated curcumin and enhanced its bioavailability to dramatically improve its therapeutic potential. Studies show curcumin has a wide distribution throughout the human body, causing a cascade of anti-inflammatory, anti-oxidant, pro-apoptotic, chemotherapeutic, and wound-healing benefits.
Overview of Potential Benefits and Risks
Disclaimer: Always consult your health care professional prior to making changes in your diet or exercise regimen, including whether to use supplements like curcumin. Pregnant women, women who are nursing, and children must always consult a physician prior to taking supplements or medications.
Below is a summary of health benefits, potential risks, side effects, and possible drug interactions associated with curcumin.
Overview of potential curcumin health benefits:
- Anti-inflammatory Benefits
- Antioxidant Benefits
- Boosting Brain Derived Neurotrophic Factor (BDNF)
- Alleviating Depression, Stabilizing Mood, and Improving Memory
- Preventing Heart Disease
- Preventing Diabetes
- Soothing Arthritis Symptoms
- Prevention of Liver Damage and Disease
- Prevention of Metabolic Syndrome
- Alleviation of Irritable Bowel Syndrome and Crohn’s disease
Overview of potential curcumin side effects and drug interactions:
- Labeled Generally Accepted as Safe (GRAS) by U.S. FDA
- Generally well tolerated when tested at doses up to 1g in clinical settings
- May cause minor side effects for a small number of people when taken in very high doses, including bloating, acid reflux, flatulence, diarrhea, headache, and skin rash
- May affect how the body processes certain medications, including antibiotics, anticoagulants, antidepressants, antihistamines, cardiovascular drugs, and chemotherapy drugs
How Does Curcumin Work?
Traditionally, medicine has focused on delivering specific drugs to specific biological targets. This is a benefit when treating conditions that have a single origin or cause, like certain types of leukemia that result from specific chromosomal abnormalities. In such cases, targeted delivery of therapeutic drugs can be extremely effective.
However, chronic conditions and age-related diseases are often the result of several underlying conditions. For example, obesity-associated cancer may be caused by dysfunction across the insulin/ iGF factor axis, cytokines, and intracellular signaling pathways like MAPK and STAT3. Even well-known and accepted facts like “heart disease may lead to stroke” are more complex than traditional medicine once believed, as research now indicates that more than 32 different genes can significantly affect risk of stroke.
For this reason, modern pharmacology has begun to shift toward a more holistic perspective on disease pathology. “Promiscuity can be a virtue” in this context, as researchers Simon Mencher and Long Wang note in a 2005 article published by the journal BMC Clinical Pharmacology. From this perspective, a chemical compound’s ability to provide therapeutic benefit to a wide range of biological targets–it’s promiscuity— may be an essential characteristic in the fight against multi-faceted age-related diseases.
Studies indicate curcumin is one such promiscuous drug, demonstrating an ability to target some of the body’s most vital signaling pathways and intracellular networks. Specifically, curcumin is thought to provide therapeutic benefit through antioxidant, anti-inflammatory, and immune-regulatory activity. Key mechanisms of actions that are believed to drive curcumin’s therapeutic potential include the following:
Neutralizing Free Radicals. Curcumin is known to prevent damage from free radicals, also known as reactive oxygen species (ROS), in two significant ways. First, it increases certain enzyme activities that ultimately represses cellular oxidation, and thus reduces free radical production. Additionally, curcumin is chemically structured in a way that neutralizes existing free radicals, which researchers call an “essential component” to the compound’s antioxidant capabilities.
Reducing Inflammation. Chronic inflammation is believed to be the single biggest factor contributing to age related disease. Curcumin appears to be a natural anti-inflammatory through at least two well documented mechanisms. First, curcumin has been shown to down-regulate the cytokines related to inflammation. Additionally, curcumin has been shown to promote the production of anti-inflammatory cytokines, like IL-10. Curcumin appears to further attenuate inflammation by favorably modulating the signaling pathways that mediate it, including NF-κB, PPAR-γ, and TLR4-MD2.
Bolstering Immunity. A third mechanism of action driving the therapeutic value of curcumin is found in its ability to promote immunity. This is achieved through direct interaction with the immune system’s most critical tools for preventing infection and disease. In a 2018 article published in the Journal of Cellular Physiology, researchers call curcumin a “nature-made jack of all trades” that can decrease the severity of various infections and diseases by bolstering t-lymphocytes, macrophages, dendritic cells, b-lymphocytes, and other immune system cells that naturally ward off infections.
Perhaps most exciting is new research that demonstrates curcumin’s potential to treat and prevent the spread of certain cancers. Studies indicate this natural plant compound may arrest cancerous cell growth, suppress its spread, and even encourage cancerous cells to deconstruct themselves via a natural process called apoptosis. However, researchers warn that more comprehensive studies and clinical trials are needed to better understand curcumin’s potential anti-cancer properties.
Curcumin Dosages and Supplements
Disclaimer: Always consult your health care professional prior to making changes in your diet or exercise regimen, including whether to use supplements containing curcumin.
As mentioned, curcumin is one of several key polyphenols in turmeric. However, natural turmeric contains just 3% curcumin. Therapeutic doses are usually range from 0.5-1.5 grams of curcumin daily, which is very difficult to get from just turmeric alone. For this reason, those who wish to attain health benefits from curcumin typically take a supplement. This is usually guided by a health professional, as the formulation and daily dosage may vary based on therapeutic needs.
Generally, clinical studies have evaluated curcumin supplementation in the following range:
- 500mg per dose
- Up to three doses daily
- Administered continually for up to 8 weeks
Moreover, curcumin has a classification of Generally Recognized as Safe (GRAS) by the United States Food and Drug Administration. Although GRAS, it is still wise to consult a physician to discuss a supplementation protocol specifically designed for the condition you wish to treat.
One potential downfall of supplementing: Curcumin is known to have poor bioavailability. However, researchers have developed a few effective ways to dramatically improve absorption and therapeutic potential. For example:
- Combining curcumin with black pepper can increase absorption by up to 2,000%, thanks to one of pepper’s alkaloids called piperine
- Combining curcumin with fenugreek seeds can cause a 45-fold increase in bioavailability
- As a fat-soluble polyphenol, curcumin is best absorbed when taken with lipids (e.g., with a high fat meal). This has led to the development of lipid-enhanced supplements, as detailed in the Enhanced Absorption section below.
Over the past few decades, several leading medical and supplement companies have spent considerable amounts of time and money to optimize the bioavailability and delivery of curcumin. This has led to several innovations, many of which have been trademarked and licensed to reputable supplement companies. Longvida® Curcumin, Meriva® Curcumin, and several others are explored in the section below.
Enhanced Absorption: Longvida® Curcumin, Phytosomes, and Other Formulations
Naturally occurring curcumin is not easily absorbed. Writing for the peer-reviewed journal Nutrients, researchers note that natural curcumin extract has a “poor pharmacokinetic profile [interaction with the body] which compromises its therapeutic potential“. Fortunately, researchers also note that various drug delivery systems can be utilized to significantly enhance cellular uptake of curcumin.
This was documented in a randomized, double-blind human study published by Nutrition Journal in 2014. In it, researchers identify the following formulations for their ability to enhance the bioavailability of curcumin, as measured by blood plasma levels following oral administration:
- Turmeric root combined with a carrier oil produced 1.7-fold higher levels compared to standardized curcumin;
- Curcumin extract combined with a phytosome formulation (a patented blend phospholipids that have fluid characteristics, like cell membranes) produced 7.9-fold higher levels compared to standardized curcumin, and;
- Curcumin extract combined with a hydrophilic (water-friendly) carrier and natural antioxidants produced 45.9-fold higher levels compared to standardized curcumin.
The takeaways from the study are clear: When it comes to curcumin, formulation matters. Taking curcumin with fat (like a phytosomal formula) or via hydrophilic carrier is the best way to significantly improve absorption and therapeutic potential. Below are a few of the most common and effective curcumin formulations.
Longvida® Curcumin is a patented formulation developed by university neuroscientists to enhance absorption and delivery, especially to the brain. Clinical trials have shown this curcumin formula to:
Meriva® Curcumin is a patented formulation developed by phytochemical and production company, Indena®. It is made using a synergistic combination of curcuminoids that show particular promise for treating joint, bone, and kidney health. Clinical trials suggest this formula may:
Theracumin® is a patented formulation developed by functional food and supplement company, Theravalues® Corporation, located in Milan, Italy. By reducing particle size, Theravalues claims the highly bioavailable form of curcumin has up to 27-fold increased absorption compared to standard curcumin powder. Substantial clinical trials are lacking at the time of this writing. However, cell and animal-based studies suggest this formula:
Curcumin C3 Complex®
Curcumin C3 Complex® is a patented formula owned by Sabinsa Corporation, a health science company headquartered in New Jersey, United States. This formulation combines curcumin with two other curcuminoids– demethoxycurcumin and bisdemethoxycurcumin– for added therapeutic potential. In clinical trials, this formula:
These are just four of the most common curcumin formulations found in health supplements. Many companies develop proprietary blends that claim to offer even better absorption than those mentioned above. Scientists are cautious about newer formulations, however. Writing for the peer-reviewed journal Molecules, researchers note that newer delivery mechanisms like micellar structuring, nano-particles, and omega-3 fatty acids are lacking in clinical evidence.
A lack of clinical evidence does not mean newer formulations are unlikely to work, however. It simply means more studies are needed to verify the extent to which things like nano-particle and omega-3 formulations improve bioavailability and delivery.
Potential Health Benefits of Curcumin
Cell, animal, and human clinical trials indicate curcumin may provide therapeutic health benefits in the following ways.
As mentioned above, inflammation is widely considered to be a key driver in several age-related diseases. For example:
- Chronic inflammation is considered to be a factor in the development of atherosclerosis, or the buildup of plaque in arteries that increases risk of heart attack and stroke
- Inflammation is also linked to America’s obesity and metabolic disease epidemic
- A 2018 meta-analysis of more than 200,000 Europeans links chronic inflammation with increased likelihood of developing mental illness
Although the relationship between inflammation and disease is complex, curcumin is proven to have anti-inflammatory properties that might play a key role in the prevention of age-related disease and degeneration (https://pubmed.ncbi.nlm.nih.gov/26007179/). More research is needed, but scientists believe curcumin’s anti-inflammatory effects are related to its ability to function as a potent antioxidant.
Antioxidant potential aside, curcumin has been shown to have a favorable impact on the body’s cytokine system. Cytokines are proteins that act as on/off switches for the immune system. Some rev things up, while others slow things down. Curcumin appears to down-regulate the cytokines that cause inflammation. At the same time, it appears to activate the cytokines that reduce inflammation.
This was illustrated in a 2020 systematic review of studies on ulcerative colitis, a chronic inflammatory disease that affects up to 900,000 Americans annually. According to researchers, “the results of the randomized clinical trials showed promising results” for patients supplementing with curcumin. Authors note, however, that more research is needed.
Research also indicates that curcumin may exert anti-inflammatory effects by having a favorable impact on the signaling pathways that control inflammation response. These enzymatic pathways include COX-2, LOX, and iNOS– by inhibiting these pathways, curcumin is thought to prevent inflammation and related disorders.
As noted above, curcumin exhibits strong antioxidant potential. Most interestingly, it has been shown to increase the activity of certain enzymes that are known to reduce oxidation, or the production of free radicals. This was published in an updated review of medical applications for curcumin in the journal, Pharmaceutics. In an analysis of 9 enzyme classes affected by curcumin, researchers found about 20% of all affected classes were oxidoreductase enzymes.
These enzymes are known to be the catalyst for electron transfer from one molecule to another. Electron transfer is critical, as it is the method by which antioxidants (which have an extra electron) neutralize free radicals (which are unstable because they are missing an electron). This is an ongoing biological process, requiring antioxidants to continually balance free radicals via electron transfer to maintain oxidative balance. By promoting oxidoreductase enzyme activity, curcumin appears to provide a foundation for these essential cellular reactions.
Moreover, some studies indicate curcumin can increase the body’s defense systems that naturally protect against free radical damage. In a review of cell and animal studies published by the peer-reviewed journal Frontiers in Pharmacology, ample evidence suggests curcumin stimulates glutathione synthesis and activates the SOD1 gene. Glutathione is known to stabilize free radicals and prevent oxidative damage, whereas SOD1 appears to act as a catalyst for the production of additional enzymes that do the same.
Boosting Brain Derived Neurotrophic Factor (BDNF)
Neurons have the amazing ability to reorganize themselves. Scientists call this property plasticity, and it’s the reason why brains are able to form new neural circuits to encode things like knowledge, motor skills, and even practices like mindfulness (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6312586/). Driving this process is a protein called Brain Derived Neurotrophic Factor (BDNF), which is produced by a gene of the same name. As of 2020, BDNF was the “most distributed and widely studied” of all mammalian nervous system proteins, and it is thought to have therapeutic potential for improving plasticity and treating depression, neurodegeneration, and brain cancer.
Some researchers are hopeful curcumin can help. Inflammation is suspected to also play a role in cognitive decline, which makes curcumin’s natural anti-inflammatory properties potentially beneficial. But the real key may lie in curcumin’s ability to promote BDNF. In one study, researchers found curcumin to promote neural plasticity in mice. Commenting on the study, authors note the changes were likely due to its impact on BDNF production and its anti-inflammatory properties.
In another study, curcumin was found to improve neurogenesis– the creation of new neurons– and enhance cognition in mice. Improved BDNF production, anti-oxidant potential, and favorable modulation of key signaling pathways are three ways curcumin appears to affect such outcomes.
Alleviating Depression, Stabilizing Mood, and Improving Memory
New research suggests that chronic inflammation and depression are linked– a correlation that was observed in a 2020 meta-analysis of twenty-two studies totaling more than 20,000 children and adolescents. Not surprisingly, curcumin’s ability to boost BDNF and reduce inflammation may also make it a viable option for treating depression and other mood disorders.
One animal study found curcumin to exhibit antidepressant-like effects on mice. Researchers attribute the effects to curcumin’s ability to increase nervous system tissue (via BDNF). Concluding the study, authors note that the results are promising and indicate “curcumin may prove an effective and lasting natural antidepressant”.
In humans, studies are even more promising. A double-blind, placebo-controlled study of 56 people found curcumin to be “significantly more effective” than placebo for individuals who suffer with major depressive disorder. Interestingly, curcumin seemed to be most beneficial for individuals who also exhibited signs of atypical depression. This subset of depression is characterized by sensitivity to rejection or criticism, mood instability, and an ability for positive news to temporarily lift depressive symptoms.
Another study indicates curcumin may benefit older populations specifically. In a double-blind, placebo-controlled study of 60 adults aged 60-85, curcumin was found to significantly improve both working memory and mood. Notably, Longvida Curcumin was the formulation tested. For more information on Longvida, see the Enhanced Absorption section above.
In addition to offering potential relief for individuals with depression and mood disorders, curcumin may also improve memory. In an 18 month long double-blind, placebo-controlled study of 40 adults, curcumin was shown to improve several measures of cognitive function, including attention and visual memory.
Preventing Heart Disease
No disease kills more people worldwide than heart disease. More than ever, researchers are combing the planet for natural supplements that can help reverse this tragic trend. And when it comes to preventing heart disease, curcumin may help.
In a 2017 article published by Pharmacological Research, scientists identify curcumin as a potential preventative compound for individuals who are at risk for cardiac disease. In the paper, researchers note that cardiac diseases are often characterized by dysfunction throughout key pathways for oxidative stress, apoptosis, and inflammation. Since curcumin demonstrates an ability to regulate these same signaling pathways, researchers believe the polyphenol may be a viable option for preventative care.
Interestingly, curcumin has been shown effective in treating one of the biggest causes of cardiac disease: Endothelial dysfunction. This condition is a type of non-obstructive coronary artery disease in which the heart’s blood vessels constrict, rather than open. In a clinical trial published by the peer-reviewed journal Aging, curcumin was found to reduce oxidative stress, increase nitric oxide availability, and increase endothelial function by 36% compared to placebo.
Diabetes is a complex, multi-faceted disease. In a review of scientific literature and animal studies, researchers conclude that curcumin plays an important role in both preventing and treating diabetes. Most notably, researchers document curcumin’s ability to address key elements of diabetes holistically and favorably. These include insulin resistance, hyperglycemia, hyperlipidemia, and necrosis.
These findings have been seen, at least in part, in humans. One of the most-cited examples is a 2012 randomized, double-blind, placebo- controlled trial of 240 adults. All subjects had medical diagnoses of “pre-diabetic” and were randomly divided into control (receiving placebo) and test (receiving curcumin) groups. After 9 months, 16% of participants who received a placebo developed type 2 diabetes. Astonishingly, zero participants who received curcumin developed the condition. Commenting on the results, researchers note curcumin also seemed to improve the function of β-cells– the cells that make insulin and ultimately help control blood sugar levels.
Soothing Arthritis Symptoms
Joint pain commonly comes in the form of arthritis. Globally, the two most common forms are rheumatoid arthritis and osteoarthritis. Studies indicate supplementing with curcumin may offer relief for both.
Rheumatoid arthritis is unique in that it is an autoimmune condition, meaning it is brought about by the immune system mistakenly attacking the body’s tissues as if they were a foreign invader. This causes damage to joint tissue and may eventually cause bone erosion, deformity, and even physical disability.
Human trials indicate curcumin may help. In a trial of 45 healthy adults, curcumin was found to provide better relief than the nonsteroidal anti-inflammatory (NSAID) drug diclofenac. The results are compelling, though researchers caution that larger scale clinical trials are needed.
Osteoarthritis is a more common form of joint paint, affecting an estimated 32 million adults in the United States alone. This type of arthritis is commonly accepted as an age-related condition brought about by a lifetime of natural wear and tear on the joints. However, curcumin may help to prevent this age-related disease as well.
In one study, adults who received 200mg of curcumin daily reported a 58% decrease in perceived symptoms after 3 months, compared to a control group that reported just “modest” improvements. In a 2019 study, curcumin was shown to provide similar pain relief as the NSAID diclofenac for individuals with knee osteoarthritis. Commenting on the study, researchers highlighted curcumin’s superior tolerance and significantly reduced chance of side effects compared to NSAIDs.
The last point is particularly important, as NSAIDs are not recommended for long term use and have well-documented adverse side effects, like increased risk of heart attack and stroke. Older individuals, and those who take NSAIDs for a prolonged period (anything over 3 or 4 days at a time) are particularly at risk. Thus, curcumin represents a viable option for aging individuals who require daily relief from osteoarthritis pain.
Prevention of Liver Damage and Disease
Curcumin may also help to prevent liver damage and disease. As noted above, individuals who treat arthritis symptoms with nonsteroidal anti-inflammatories (NSAIDs) are at risk of several adverse side effects that get worse over time, including increased risk of heart attack and stroke. But those side effects also include liver damage, as published by the peer-reviewed World Journal of Gastroenterology. Thus, anyone taking NSAIDs for a prolonged period of time– whether it’s for arthritis or any other form of pain management– may avoid the risk of liver damage by using curcumin instead. More research is needed, however.
Additionally, research indicates curcumin may help to prevent the buildup of fat in individuals with hepatic steatosis, or non-alcoholic fatty liver disease. More research and clinical trials are needed, although a 2019 systematic review and meta-analysis indicates curcumin may have a “favorable impact” on the disease.
Prevention of Metabolic Syndrome
In addition to fatty liver disease, a summary of curcumin studies indicates the polyphenol may help to prevent or delay the onset of other metabolic diseases, including polycystic ovary syndrome, metabolic syndrome, glycemic disorders, cardiovascular disease, and atherosclerosis in particular.
Alleviation of Irritable Bowel Syndrome and Crohn’s disease
Crohn’s disease is another autoimmune condition for which curcumin supplementation is often recommended. As cited above, curcumin shows efficacy as both an anti-inflammatory and a natural treatment for other autoimmune conditions, like rheumatoid arthritis. Although anecdotal evidence suggests curcumin is effective in treating Crohn’s disease, a comprehensive 2019 meta-analysis published by the British Society of Gastroenterology cautions against using curcumin, as research is still limited. Nevertheless, authors call curcumin a “promising candidate” for alleviating the symptoms of IBS and Crohn’s.
At the very least, curcumin shows efficacy when paired with the medication mesalamine, an NSAID commonly prescribed to patients with ulcerative colitis and Crohn’s disease. Notably, the curcumin-mesalamine combination was shown to be more likely to induce remission– and thus, relief from symptoms– than mesalamine alone.
Potential Side Effects and Drug Interactions
As cited above, the U.S. Food and Drug Administration labels curcumin a Generally Recognized as Safe, or GRAS, food item. In research settings, very few adverse side effects have been observed. Most studies highlight the fact that curcumin is non-toxic and generally well-tolerated.
For some people, high doses of curcumin may cause minor side effects like:
- Acid reflux
- Flatulence and diarrhea
- Skin rash – rare, and occurred in one study that tested an extremely high dosage of 8 grams
Conclusion: Through Promiscuous Delivery, Curcumin is a Safe and Powerful Supplement
Ancient Ayurvedic and Chinese Medicine practitioners have long relied on the medicinal power of turmeric– and its primary phytochemical curcumin– to promote wellness and treat common conditions like headache and fever. Today, a growing body of cell, animal, and human research indicates curcumin extracts to be even more potent and therapeutic. Inflammation, arthritis, and autoimmune disease are just a few of the major conditions this powerful spice has been shown to alleviate.
With immense upside and a nearly impeccable safety profile, research indicates dietary turmeric and curcumin supplements represent an essential addition to most health and longevity regimens.