Turmeric is a root belonging to the ginger family, and like ginger, is used prominently in oriental cuisines. Owing its yellow color to a compound called curcumin, the root is probably best known as the spice used in curries. Like its ginger cousin, turmeric has been used for medicinal purposes for thousands of years. I’m not entirely sure how we know the timeline or how much truth is in that statement. Nonetheless, I will parrot that as truth since we as humans often have this immutable faith in the supposed medicinal value of things we pull out of the ground. As it turns out, there does appear to be some real potential medical applications, not with turmeric itself, but with curcumin. Some of the claims are hype, some of them show a lot of promise with a little more research, and there may actually be some benefit in taking curcumin now.
Curcumin was identified as a compound in turmeric in the 1800’s, but the biological importance of curcumin was not touched on until 1949 when a paper published in Nature described the antibacterial properties of curcumin, specifically, the ability to inhibit the growth of Staphylococcus aureus. Scientists gave little attention to curcumin over the next 25 years when it was discovered that curcumin exhibited anti-inflammatory and anti-oxidant activity, and then anti-cancer activity by the mid-1980’s. Since that period of time, curcumin has been heralded in scientific circles as a potential safe, effective, treatment or preventative measure to many difficult to treat diseases.
I will touch on only a few areas that are being investigated, of which effect me personally in some way. Curcumin-related therapy is a topic surprisingly deep in scope and I could not possibly cover every aspect. Moreover, I am attempting to draw from evidence in peer-reviewed science provided by experts on the subject and I am by no means an expert myself.
Cystic fibrosis or CF is an inherited genetic disorder and something that I am personally afflicted with. CF results in the mutation of a gene that codes for a protein called CFTR. This mutation causes the CFTR protein to be absent or malfunctioning in people who have CF and leads to the inability to properly transport water and salt across cells lining important organs such as the lungs, pancreas and small intestines. Ultimately, this causes thick mucous build up in the affected organs and significantly damages the lungs over time, facilitated by recurring bacteria infection, eventually leading to mortality with a current average life expectancy of 38 years old.
Its thought that curcumin can restore some function to the CFTR protein, and this is what drew my attention to curcumin. The hype began when a study published in 2004 purported that curcumin was able to correct the defect in CF mice with the most common mutation, referred to as delta F508, improving their survival rate, and in cell culture. However, another group independently attempted to recreate these results and were unable to achieve even a modest affect as a result of curcumin given to CF mice or in cell culture, citing potential flaws in the original study design and perhaps misinterpreting the apparent reasons behind the increased survival rate in mice. These negative results were again confirmed in epithelial cells, Baby Hamster Kidney cells and other cell lines exposed to curcumin. Its worth noting, however, that one lab did find that curcumin restored function in CFTR in a delta F508 cell line, although with methods differing from those previous studies. More recently, a study found that a combination of curcumin and genistein improved CFTR function in cell lines containing the less common G551D mutation.
Overwhelmingly, however, the evidence does not suggest that curcumin will improve the health of people with CF. It is interesting that curcumin persists in the scientific literature as a CFTR inducer. Maybe there will be good reason to include as part of a therapeutic regiment in the future with an improved curcumin formulation. There’s no harm in taking curcumin though and it may actually provide other positive health benefits. The real harm comes from naturalists touting curcumin and other natural substances as a cure, which may be enough to convince some people to stop their currently suggested therapeutic routines and pharmaceuticals that are backed by real clinical science, robbing them of any hope of a long life. This seems to be an unfortunate reality based on the little reading I’ve done online.
Alzheimer’s Disease (AD) is a form of dementia characterized by a progressive deterioration of cognitive function, loss of memory, behavioral and personality changes. AD patients form amyloid-β-protein aggregates in the brain over time, which are essentially abnormal deposits of protein, or plaques, that aren’t supposed to be there. As a result neurons die off and the plaques interfere with the ability of existing neurons in the brain to communicate with each other.
Brain disorders are extremely difficult to treat because the obvious difficulty in studying the brain itself but also because any drugs have to cross the blood brain barrier, which is our bodies natural defense that keeps harmful agents from reaching our most vital organ. Any substance we use to treat a brain disorder needs to have the ability to cross the blood brain barrier naturally, or we need to find ways to “trick” our bodies into allowing it pass to the brain.
It appears that curcumin is one of those molecules that are allowed to pass the blood brain barrier, at least when given to mice at high doses. A link between AD and curcumin was originally drawn from epidemiological data that shows India has a much lower incidence of AD than the US. In fact, current data from The World Health Organization shows that American’s are 8 times more likely to die of Alzheimer’s than Indians. It must be something in the diet….or it could be that Americans are expected to live 10 years longer than Indians, or that Alzheimer’s Disease is severely under reported in a country faced with extreme poverty.
There actually has been a study using survey data reporting the amount of curry consumption in the Asian elderly population and found a positive association between curry consumption and improved cognitive function, again this kind of data should be taken with a grain of salt since this is not a controlled study and the observed effect could be due to any number of factors. There has also been a wealth of evidence shown in the lab using rodents and cell culture to demonstrate that curcumin inhibits formation of amyloid-β-protein aggregates, restores synaptic plasticity, and protects neurons. Unfortunately, there has been no improvement shown in humans with AD who take curcumin in clinical trials. This may suggest that curcumin can only help prevent AD, or that not enough of it is reaching the brain to cause a clinically significant effect due to poor bio-availability (explained in the last section of the article).
Cancer is the second leading cause of the death in the US, right below heart disease and there’s no real indication of that changing soon. In addition to environmental and genetic factors, cancer is largely an unfortunate side effect of aging. As we live longer, cancer is bound to become more prevalent.
Cancer is such a difficult disease to treat because there is nearly an infinite number of ways that cancer can manifest itself beginning at the cellular level and involves multiple cumulative steps that take place over several years. To further compound the problem, different tissue types present unique challenges. We need to find ways to target the cancer cells specifically while leaving the normal cells alone. Not an easy task when those cancer cells are your cells. Most effective therapies that we use to treat diseases today target something that is foreign to the body, like bacteria. We can target these with minimal effect to the person being treated because the bacterial cells are different on a molecular level than cells that originate from us.
Despite all the promising research that is coming forward, the best we can do to treat cancer comes in the form of approaches that “poison” the cancer, but also damages normal cells in hopes that we can kill the cancer without taking out the person too. It sounds archaic because it is. It’s like using a wrecking ball to remove one window in a building.
So the future in cancer therapy is targeted and individual treatment. Something that will target the cancer cells specifically and therapy that can be catered to an individual based on specific properties of their cancer. Cancer prevention is the next best thing we can currently offer, and we now know that diet plays an important role in prevention. As we’ll see, curcumin may potentially have a role in both prevention and treatment.
In 1987, the first clinical trial using an ointment containing curcumin on patients with cancerous lesions on the skin found a reduction (90%) in symptoms and a small (10%) reduction in the size and pain of the lesions. Since then, multiple studies involving mice and cell culture have found curcumin to be effective in treating multiple types of cancers by multiple mechanisms: stopping cancer cell proliferation, blocking various transcription factors, inhibiting inflammation, providing antioxidant activity and causing apoptosis (cell death) specifically in cancer cells.
However, these dramatic and almost miraculous effects observed in the lab have not been duplicated in human clinical trials, most likely due to poor bio-availability of curcumin (again, I cover this in the final section of this article since this is a limiting factor in all curcumin-related therapies). One study did find that an oral dose of no less than 4 g of curcumin a day may improve the prevention of colorectal cancer. Another study found a reduction in size and number of polyps in patients genetically predisposed to colorectal cancer with treatment combination of 480 mg of curcumin and quercetin 20 mg orally 3 times a day over the course of 6 months. Curcumin was also found to be effective in slowing the progression of pancreatic cancer in a limited number of patients given 8 g of oral curcumin a day.
So, given what we know, curcumin may be helpful in the prevention and slowing of cancers that most directly involve the colon and pancreas.
One of the first clinical properties discovered in curcumin was its ability to act as an anti-inflammatory agent by inhibiting pro-inflammatory cytokines. It should follow that curcumin would be an effective treatment for arthritis, there is plenty of evidence from studies performed in the lab, but a surprising lack of clinical data specifically assessing arthritis treated with curcumin.
The most solid study I could find was a pilot study comparing the effectiveness of daily 500 mg curcumin, 50 mg of diclofenac sodium (a traditional nonsteroidal anti-inflammatory drug (NSAID) used to treat arthritis), or a combination of both in patients with rheumatoid arthritis over 8 weeks. The curcumin used in this study was a patented formulation with supposed improved bio-availability called BCM-95. Overall, they found BCM-95 curcumin and curcumin+diclofenac to be just as effective, if not more effective at relieving pain and symptoms than diclofenac alone. Providing some evidence that curcumin could be used to supplement treatment of arthritis.
Failure of Curcumin to Deliver
So why does curcumin appear to succeed so often in the lab in a way that can’t be repeated in humans? The most likely answer is due to poor bio-availability of curcumin. Meaning, the amount of active curcumin that reaches the blood stream is well below the amount needed to cause a clinically significant change. Consuming turmeric root alone, which has very little curcumin to begin with, provides the absolute least amount of bio-available curcumin. High doses of isolated curcumin, even though there may be detectable levels in the blood stream, is still metabolized too quickly to be meaningful. However, a daily dose of at least 3.6 g of curcumin a day does appear to result in a quantity necessary to exert an effect in colorectal tissue, since this is one of the first places curcumin will pass after consumption. This is probably the reason curcumin appears to be effective in preventing colorectal cancers.
The major reasons for bio-availability are due to curcumin being water insoluble and fast metabolism upon reaching the gut. Little of the compound reaches the liver or systemic circulation, and 40% is excreted in the feces unchanged. To circumvent this problem, multiple strategies are being developed to modify the structure or encapsulating curcumin for improved uptake by the body and survival in the blood stream.
One such formulation with improved bio-availability that I have already mentioned was BCM-95 which is backed by at least one clinical trial that I have cited involving arthritis. Other brands currently available for purchase include Longvida and Meriva. I can not speak of the effectiveness for any of these. However, I have to imagine that any of those brands must be more effective, or just as effective at the very least, than curcumin alone based on the wealth of evidence we have on curcumin studies. So far there has been no dose related toxicity reported with curcumin that I am aware of.
I’ll end with a word of caution that whatever you use should never replace, but rather compliment traditional treatments prescribed by your doctor. Curcumin could potentially offer some relief for arthritis and help prevent cancer and alzheimer’s disease.