Turmeric: The Medicinal Wonder Spice

Turmeric Picture.jpg

Turmeric...

One herb to rule them all.

The market for turmeric has exploded over the past few years as both a supplement and food ingredient. At The Herbal Equivalent, we find it fascinating the amount of research that’s been conducted on turmeric for a host of different applications, and that it’s only recently caught on in the western world despite it having roots in ancient medicinal practices for a few thousand years. If you’re not privy to what it is, turmeric is a yellow-orange root that resembles a more finger-like appearance of ginger and is commonly used as a spice in Indian and Thai cuisines. It also shows up in some more ancient forms of medicine like Ayurveda, a holistic practice stemming from Indian origin. People have long known about the medicinal benefits of turmeric as an anti-inflammatory, but more recently we’ve seen an uptick in the amount of emphasis placed on its use in modern medicine due to its low side effect profile in comparison to other traditional medications.

If you haven’t heard about the purported benefits of turmeric, it’s touted as almost a cure-all or panacea supplement, but we’re only going to focus on a few of the main claims about turmeric and examine the research that either supports or refutes each. These include:

  1. Anti-inflammatory - turmeric has some interesting properties where it is claimed to help support a healthy inflammation response systemically or locally, depending on the exact application.

  2. Antioxidant capacity - a class of compounds in turmeric called curcuminoids hold promise for being potent antioxidants and may play a role in reducing oxidative stress.

  3. Cardiovascular and heart benefits - we hear about these curcuminoids being able to mitigate some detrimental effects of bad blood lipid profiles and provide some benefit to overall cardiovascular health by dilating the blood vessels.

  4. Benefiting cognition - ever popular is the claim that turmeric may be able to offset the progression of age related cognitive decline and some neurodegenerative disorders.

  5. Antidepressant activity - this one is interesting. With the upsurge in pharmaceutical antidepressant use, we would love to see another useful alternative with less side effects than conventional approaches.

  6. Better digestion - turmeric is said to help keep your bathroom habits on the more normal end by aiding digestive processes. Should you add some TM to help you BM?

Despite plenty of anecdotal evidence to support these claims, we really wanted to see what the clinical trials looked like, especially since turmeric has reached a panacea status in the supplement world and we’re always the great skeptics.

It should be noted that turmeric supplementation does not come without a caveat. The curcminoids in this spice are notoriously difficult to absorb, so some sort of enhancement is required in order to achieve many of these effects. If you decide to take turmeric, it would behoove you to find a supplement which combines it with black pepper, which is the most common (and typically cheapest) absorption enhancer (1). Other than that, nanoparticulated turmeric, water soluble, and phosphatidylcholine bound forms all have the ability to be absorbed quite readily, but also come with a hefty price tag (2-5). It should be noted that the phosphatidylcholine form failed to reach significant levels of curcuminoids in the blood in humans to enact the high anti-inflammatory response seen with black pepper formulations, though reached better levels in rats (2-3). Hint hint: this is why we don’t really like citing rat research. We must also point out that there may be potential bias involved in the nanoparticle curcumin studies due to a specific patented formulation being used, but the research does show quite a substantial increase in absorption (4-5). Honestly, we would recommend a simple black pepper formula for the sake of cost and how it’s been proven for nearly 20 years to work.

*Another Note:* We will be using turmeric and curcumin interchangeably in this post. Curcumin is the primary constituent of turmeric which is responsible for most of the effects. Most of the research does use a more concentrated form with a 90-95% standardized extract of curcuminoids, so take that into consideration when looking for a supplement.

Anti-inflammatory

Research actually demonstrates quite a great response to inflammatory disorders with turmeric or curcumin supplementation. The most commonly investigated is with that of joint pain and osteoarthritis (6). A recent meta-analysis concluded that curcuminoid supplementation demonstrated no signficiant difference in pain outcomes when compared to traditional anti-inflammatory medications like ibuprofen when averaged at around 1000 mg per day of curcmin (7). While the overall number of good research articles on turmeric in humans for this effect is low, it offers a great stepping stone to further research and many people have already seen benefits from using the supplement for joint health. But basically, it tells us that so far that curcumin performs just as well as common over-the-counter drugs for pain.

Other research evaluating the anti-inflammatory actions of curcuminoids find that they may be useful in other health states characterized by high inflammation. One paper suggests that curcumin extract may be beneficial in maintaining remission of ulcerative colitis, though has not been tested as a potential treatment (8). This study also used curcumin as an adjunct therapy, meaning that standard drugs were used simultaneously and therefore does not validate curcumin as a standalone maintenance drug. A larger pilot study of 500 people found decent improvement in irritable bowel syndrome symptoms with curcumin supplementation, though the full paper could not be accessed and assessed properly to determine any potential confounders (9). Another study found no significant difference between placebo and curcumin supplementation in IBS symptoms overall, however, the low dosage at 60 mg may explain the lack of benefit here as a higher dose is typically needed due to the low absorption of curcuminoids (10). We’ve intentionally left out a few other studies on inflammation in the gut, as they are typically confounded with standard medication use and therefore only demonstrate turmeric having capacity as an adjunct therapy at this time.

A few other studies demonstrate a degree of benefit in terms of curcumin application for reducing localized inflammation, particularly in gingivitis (11). We left out several of these studies due to their simultaneous administration of standard medications. Unfortunately, many of the studies examining the anti-inflammatory benefits of turmeric and curcumin outside of joint issues tend to use it primarily as an adjunct therapy. While this does not invalidate the effects of turmeric, it doesn’t let us draw the conclusions we would like to with curcuminoids being the main active therapeutic ingredient.

Another study examined the benefits of turmeric on systemic inflammation like as seen with lupus. This paper suggest that turmeric may have the ability to reduce pro-inflammatory cytokines in the blood, which can help to support a more normalized inflammatory response (12). Other research has demonstrated the capacity of turmeric to help reduce markers of inflammation in almost all research applications (i.e. petri dish, rats, and humans). While these are great stepping stones to further studies, we can’t really draw any definitive conclusions of the exact effects of supplementation on certain disease states, though the current research does look promising.

Antioxidant Capacity

You may have heard about turmeric being a highly potent antioxidant spice, and this assertion would be correct. In combination with its anti-inflammatory effects, curcuminoids have been researched as a potential therapeutic agent in a variety of cancers. We must point out at first that many of these trials are confounded by standard pharmaceutical interventions, and curcumin is typically used as an adjunct therapy and not a standalone therapy. What this means is that turmeric may actually hold more potential when used in conjunction with medication than on its own. We certainly do not suggest that anyone take the findings of the following research studies to attempt treatment, but rather that turmeric may be discussed with a proper medical professional as a potential adjunct. Again, consult your doctor, as these studies do not point to turmeric as a cure or treatment for disease.

Interest in the effects of curcumin as an adjunct therapy has sparked a plethora of trials on its benefits for cancer (13-17). The number of clinical trials investigating turmeric in cancer therapy is numerous, but many were primarily exploratory studies on the tolerance and safety of the supplement. Many of these studies, as referenced in a larger review article, examined certain indicators of cancer cell activity, and found that turmeric had the ability to suppress inflammatory and mutagenic biomarkers associated with increased tumor cell activity (18). There are many more of these studies currently being conducted, and the research is far from conclusive, but the preliminary evidence shows that turmeric and curcumin in high enough doses may be effective as an adjunct therapy. For now, and to be safe, we are going to leave this topic on the table and suggest that if you want more information on the safety and efficacy of turmeric in these types of applications, that you consult a qualified medical professional and do some personal research of your own.

Cardiovascular Benefits

Unfortunately, the majority of the research on turmeric’s effects on cardiovascular health revolves around rat studies, but we were able to find a few human studies. In a research study conducted on healthy people, curcumin was able to improve endothelial functioning by increasing overall blood flow through arterial dilation (19). Another study demonstrated that when curcumin is combined with plant phytosterols, it exhibits a greater lowering of LDL particle number than either phytosterols or curcumin alone (20). In this same study, however, curcumin alone did not reach statistical significance for reducing LDL blood concentration. A recent meta-analysis which evaluated mostly high quality and longer duration studies found mixed results among the research with regards to the effects of turmeric and curcumin on blood lipid levels (21). It appears that those with various metabolic disorders and other risk factors for cardiovascular disease derive the most benefit from supplementation in terms of reduced LDL and triglyceride levels. The effect is small and also appears to be dose dependent and further dependent on the bioavailability of the curcumin. This is another great reason why enhancements are necessary!

All in all, the limitations of the human studies on turmeric and cardiovascular health leave room for much more extensive research. However, it appears promising for those with high risk factors and also for keeping blood vessels pliable and open. Turmeric doesn’t look like the best heart supplement out there, but may be better when paired with other things like plant phytosterols or garlic.

Cognitive Benefits

Due to the high prevalence of Alzheimer’s and dementia, researchers have been looking tirelessly for solutions with low side effect profiles. Plenty of health gurus and marketing companies are also willing to sell remedies to desperate people, with turmeric and curcumin included. Let’s take a look at what the research shows us so far on how turmeric may provide some cognitive benefit and neuroprotection.

Curcumin has been demonstrated in vitro (petri dish) to inhibit beta-amyloid plaque formation and also assist processes to begin their breakdown (22-23). Combined with the antioxidant effects, potential cholesterol lowering effects, and general protective nature of curcuminoids, this sparked interest in exploring the spice as a potential treatment or adjunct therapy, but the results in humans have not been very promising so far (24-25). There are some limitations though due to the low bioavailability of the curcumin used in some studies. The rat research actually looks very promising, though rats tend to experience better curcuminoid absorption versus humans and of course we are not rats. The available human clinical trials are too few and much of the overall research is still very new, and much of it is not available yet. I think we’ll actually come back to this one at a later time. The in vitro studies make turmeric appear god-like in its powers, which is much of the reason why it’s exploded into such a popular supplement and food additive recently. While we aren’t saying the effects aren’t there, the research isn’t very extensive on humans in this regard, so we can’t make any definitive conclusions just yet.

One interesting study on older adults with prediabetes found that 1 gram of turmeric supplementation alongside a meal consisting of plain white bread had the potential to increase working memory by a small, but significant amount when compared to cinnamon or a combination of the two (26). First, we’re unsure of why the researchers decided it was a good idea to feed white bread to pre diabetics, and second, while this study is far from conclusive, it may demonstrate that turmeric has the potential to help those with metabolic dysfunction when it comes to cognitive performance. As we talked about earlier, turmeric appears to have more benefits for cardiovascular health in those with metabolic disorders, and this might be true of cognition as well.

Curcuminoids appear to be neuroprotective though, and may help to alleviate some of the effects of aging on cognitive decline (27-28). This is likely due to the high antioxidant content and the ability of turmeric to mitigate oxidative stress, a hallmark of cognitive disorders. At this time, the research points to this spice as having more of a protective effect and less of a therapeutic one, though somehow the researchers haven’t solved the problem of curcumin absorption despite the evidence of absorption enhancement going back two decades (1). As smart as some researchers may be, it’s almost like the scientific community expects them to act ignorant - part of the reason Blake left the research world.

Antidepressant Activity

Antidepressants are some of the top selling medications in the west, right under cholesterol lowering statins. Due to the nature of how antidepressants work in the body (read: completely messing up your brain chemistry in attempts to normalize it), they tend to have a plethora of nasty side effects. We’ve been searching for more natural and less harmful treatments, and turmeric started to make its appearance in recent years with health gurus telling everyone that it is a natural antidepressant pill. Some of this research, as with the research on cancer and heart disease, tends to be confounded with pharmaceutical usage, so take these studies with a grain of salt.

A well conducted study assessed the effects of curcumin plus an antidepressant versus an antidepressant plus a placebo. They found that curcumin group experienced a greater reduction in depressive symptoms, suggesting that it may have additive effects with the medication (29). A recent meta-analysis of six clinical trials found that there is significant support in the use of turmeric and curcumin with depression (30). A review paper suggested that the primary benefits of turmeric on depression and other psychiatric disorders is due to the potent antioxidant and neuroprotective qualities of curcuminoids (31). So far, it seems that this supplement may be useful both as an adjunct therapy and a standalone therapy, as long as proper dosage, absorption, and individual differences between patients are considered. Longer trials and more intensive measures would be useful in fully determining whether or not curcumin could work for most people and if the effects are long lasting or not. Of course, as we warn, don’t go trying to treat yourself without doctor supervision. We’re only reviewing the evidence here, so always seek the advice of a medical professional if you would like to attempt any sort of treatment.

Better Digestion

Turmeric is promoted as a digestion enhancer due to its ability to stimulate gastric juices and processes. The extreme version of this is seen with a common side effect of high dose curcumin causing diarrhea in many studies. However, in more appropriate doses, turmeric may be able to support better digestion through a few different mechanisms.

First, curcumin has been demonstrated to stimulate gallbladder emptying at low doses, indicating a possible benefit for aiding fat digestion due to the emulsification properties of bile acid (32). This is good news for those with a difficult time digesting fats, though we would need some studies investigating how turmeric may actually affect the overall digestion rate of various foods versus placebo to really make any definitive conclusions.

Second, a study examined curcumin supplementation and its effects on intestinal wall permeability and found tighter junctions and improved barrier functioning (33). For all of those people worried about leaky gut, it appears that curcumin might be a promising supplement to add to your regimen so long as an enhancement is NOT used. This is important as you actually would want the curcumin to be exposed to the entire lining of the digestive tract rather than be absorbed readily.

Third, while we could not find any direct studies on humans and enhanced intestinal motility due to curcumin, it makes sense via the stimulation of diarrhea seen as a common side effect of high doses. I know that it’s not the most scientific of assessments, but diarrhea tends to be a side effect of hypermotility in the gut. It seems like turmeric may be a good basic digestive aid and may be best when mixed in foods or taken with meals. Just be sure not to consume beyond your limit because of the potential for toilet splatters.

Other Considerations

Turmeric looks like an overall great supplement or food additive to the diet. It shows the most promise for its anti-inflammatory and antioxidant effects, and there really needs to be more research on its role in various disease states. It also has some decent preliminary evidence for depression and neuroprotective benefits. Unless your goal is the digestive benefits, an enhanced supplement would be necessary in order to achieve proper absorption and blood levels of curcumin. We’ve had luck with simple piperine (black pepper) enhancements, as they tend to be the most affordable and proven as well. Keep in mind that you can consume turmeric as a spice or the whole root without requiring a supplement, but if you’re like Blake and you hate the taste of it in most things, get a capsule.

What is really irritating about looking over many of the studies is how ignorant the researchers seem to be with regards to curcumin’s poor absorption. Most even acknowledge in the conclusions that it is a major limitation of their study, and we have the evidence going back for two decades now about how to enhance curcumin absorption. If the researchers could “solve” this problem, we may actually see some better outcomes of the research. For now, we see that curcumin is amazing in vitro, which is what some of the more overblown versions of the claims are based on. The rat research looks promising as well, but of course we aren’t rats, and they actually have higher blood levels of curcumin from the same formulations when compared to humans.

Dosing seems to range depending on the specific benefits you’re looking for, but around 1 gram seems sufficient for inflammation, cognitive, and mood support. Lower doses are fine for digestive benefits, and it appears that higher doses are being used in many of the cancer studies. I find that turmeric has benefits for my tendonitis when it flares up, but I’ve never experienced any benefits outside of that likely due to my inability to measure the other minor changes that can potentially occur.

Side Effects

The studies note that gastrointestinal side effects are the most common with symptoms like nausea and diarrhea becoming prevalent at higher doses. Some other side effects which may occur in some people include dizziness, increased risk of bleeding, and low blood pressure. It would be wise to check if there are any contraindications between supplementing turmeric and any medications you may take, but the most common interactions are with blood pressure and blood thinning medicines.

Less talked about is how high curcumin concentration may actually cause DNA damage, but the effects have only been noted so far in vitro and in rats. This happens when antioxidants are supplemented in very high amounts, as they begin to have a pro-oxidative effect. High doses of curcumin have been found to be safe so far, but very long term studies may shed some light on whether or not there is a toxicity difference between extracted curcumin and turmeric as a whole food and spice - which is how it has been traditionally consumed in large amounts. To be on the safe side, if you plan to use high doses of turmeric, use the whole spice rather than an extracted form high in curcumin.

Final Thoughts

Is it worth taking? As long as you don’t take any medications with contraindications, then turmeric appears to be a very healthy addition to your diet or supplement regimen. Take it however you want, but be sure to enhance the absorption with black pepper unless you’re taking it for digestion. It is speculated that turmeric could be a key component of the health and longevity of Asian and Indian populations, so let that sit on your mind for a bit and draw your own conclusions. I think it’s a wonderful anti-inflammatory and definitely worth taking.

Let us know your thoughts and experience with turmeric either in the comments below or by emailing us at info@theherbalequivalent.com. Be sure to check out our podcast episode on turmeric, like us on facebook, and follow us on instagram. Always remember that H = Health!

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