Healing with Enhanced-Bioavailable Curcumin

Lisa Murray, RDN

Back in 2013, during a treadmill session at the gym, my attention was diverted and I “lost my balance,” to put it simply. But the injury was not so simple and I was not healing. A year later, still without full function, I was walking by a health food store and went in for a few items. On display and on sale was a very potent, new-generation turmeric extract. I decided to try it.

Within days, I felt a difference, and within three months I felt that I was functioning normally again.

I had previously tried using standardized turmeric capsules without success, as I was unable to tolerate the burning and indigestion they caused. However, this potent yet well-tolerated form of turmeric extract quickly expedited my recovery in ways I didn’t even understand. To me, it was simply a miracle, and I became a true convert.

Since then, I’ve reviewed research showing turmeric’s modes of action, along with the challenges it presents in terms of bioavailability. Here’s what clinical studies reveal about the most efficacious new forms of turmeric and curcumin—and why it’s so hard to choose among the new compositions and products.

Curcumin’s recent history

In the past 15 years, knowledge of the many health benefits of turmeric has been increasing, and so has research on its bioactive components. The component within turmeric tagged for highest biological action is curcumin.

However, many factors affect curcumin’s efficacy as a stand-alone agent:

It has very poor solubility because it’s primarily fat soluble
It rapidly degrades at physiological pH
It is poorly absorbed in the gut
It is rapidly metabolized
It is rapidly eliminated

In addition to poor solubility and absorption, curcumin is highly conjugated in first-pass metabolism into metabolites of curcumin glucuronide and curcumin sulfate, which do not have the same bioactive properties of curcumin. This presystemic metabolism greatly reduces the amount of curcumin that can reach systemic circulation, necessitating very large doses to achieve any systemic effect.

However, black pepper extract (piperine) is a known inhibitor of hepatic and intestinal glucuronidation, and thus enhances bioavailability by preventing a significant portion of curcumin’s conversion to its metabolite. Modern research has validated this ancient combination, and it certainly worked for me. But piperine as an adjuvant may be undesirable for certain patient populations, and it can interact with a variety of drugs, in which case other alternatives may be more desirable.

Scientific efforts to enhance the absorbability and bioavailability of curcumin have led to a new generation of curcumin products delivering measurable health benefits at smaller doses, and without the use of black pepper extract. But this has also led to what I call the “bioavailability wars.”

The first salvo

A dozen or more years ago, standardized 95% curcumin extracts (a.k.a. C95) entered the market. Although these products were a step above powdered turmeric in capsules, they still had limited absorption, bioavailability, and beneficial action. However, it is worth noting that good-quality C95 has useful applications for the GI tract. If you want turmeric to hang around a while in the intestinal tract, then you might not want a highly absorbable form anyway. This extract tends to accumulate in the GI tissues and exert inflammatory balancing and antioxidant effects there.

But the downside of cheaper readily available brands of either turmeric powder or curcumin are that they can cause indigestion or a burning sensation in the stomach and upper GI, as I experienced myself. That’s why it’s important to explain the difference to patients who may have tried turmeric or curcumin in the past. The newer products do not have these side effects and are usually well tolerated.

But how do you decide which of these newer formulations is the most bioavailable?

The problem with bioavailability measurements

Today’s curcumin suppliers want to provide evidence that their product is absorbable and soluble. Each formulation claims to be more bioavailable than the others.

Standardized 95% curcumin is the product most widely used for comparison when testing bioavailability of new curcumin compositions. But although safety and bioavailability studies are conducted before human clinical trials, there has been no standardization regarding study methodology or metrics in order to make easy comparisons. As a result, these studies have measured bioavailability in very different ways and with very different doses.

Claims that a product is “10 times,” “29 times,” or “65 times” more bioavailable when compared with raw or standardized curcumin are often based on only one study, and are usually not well substantiated by further research and reproducible results. The same can also be said about the few studies comparing various products’ bioavailability against each other—it’s difficult to draw objective conclusions because the studies have not been repeated and validated.

So maybe it’s more important to study these products’ efficacy in human clinical trials. Most are showing very positive results, so it seems safe to say that all of the newer curcumin products discussed below have proven to be absorbable and bioavailable.

Which ingredient is best? I think it’s a little like putting an apple, an orange, a banana and a mango on the table and asking: “Which tastes better?” Perhaps someday, we may have a large, validated body of evidence comparing bioavailability “apples to apples,” but until then, we have a big bowl of fruit to choose from—and it’s all pretty good.

Longvida: great success in cognitive research

Many people don’t know much about this branded ingredient, so I’m choosing to start here. Verdure Sciences is the manufacturer and supplier of Longvida brand curcumin. According to the manufacturer, Longvida Optimized Curcumin uses a patented lipophilic matrix which preserves and protects the curcumin from the harsh environment of the stomach, dissolves it at the point of absorption in the GI tract, and delivers the efficacious free form of curcumin (also called intact or native curcumin) into the blood and tissues and across the blood-brain barrier.

Solid Lipid Curcumin Particle Technology (SLCP™) protects the curcumin in Longvida from being rapidly broken down and excreted, which allows for 24-hour circulation in the bloodstream. One 400 mg capsule of Longvida contains 80 mg of curcumin. Verdure Sciences claims Longvida is 95 times more bioavailable than standardized 95% curcumin.

Longvida’s formulation was originally developed by UCLA neuroscientists investigating the action of curcumin. In vitro and in vivo animal research concluded that curcumin effectively disaggregates amyloid-beta plaques as well as prevents fibril and oligomer formation. Studies using Longvida showed it improved the memory of mice with high levels of amyloid-beta. Although mouse brains and human brains differ in their utilization and clearance of curcumin, published human studies also show a reduction in plasma beta-amyloid.

Researchers at UCLA studied Longvida’s actions on tau formations as well. A study published in December 2012 in the Journal of Biological Chemistry is one of the first to reveal the relationship between pre-tangle tau, brain-cell death, and cognitive function. The study showed that Longvida restored memory in mice with cognitive dysfunction caused by tau.

A landmark randomized, double-blind, placebo-controlled human study published in the Journal of Psychopharmacology in May 2015 was the first to show that daily Longvida (400 mg) curcumin supports cognitive function in healthy subjects—including measures for memory, attention, fatigue, stress, and mood—versus the placebo group.

The bottom line is that curcumin can cross the blood brain barrier … if it can get there. The historical challenges with less bioavailable forms of curcumin have been that very little of it enters systemic circulation, and then it is rapidly taken up into a variety of tissues. Longvida’s composition protects and delivers curcumin into circulation—and is shown to stay in circulation for a significant amount of time, cross the blood-brain barrier, and exert beneficial effects. Efficacy was achieved with doses as small as 200 mg.

Meriva: using phytosomes for better dispersion, solubility, and absorption

Meriva is a patented curcumin-phytosome formulation from Indena. Meriva is formulated in a 1:2 weight ratio of curcumin and lecithin (consisting mainly of phosphatidylcholine) with an overall 20% curcumin content in the final product. One 500 mg capsule of Meriva contains 100 mg of curcumin.

By complexing a polyphenol such as curcumin with phosphatidylcholine (PC) to make a phytosome, the new molecule adopts the superior solubility properties of PC, which is amphiphilic-hydrosoluble on one end and fat soluble on the other. This allows easier passage through tissues and cell membranes for absorption. The dispersion, absorption and bioavailability of curcumin molecules is thus greatly enhanced, according to Indena, which claims Meriva is 29 times more bioavailable than standardized curcumin.

There are now over 25 clinical studies concluding that a moderate dose of Meriva (1000-2000 mg per day, equivalent to 200-400 mg of curcumin) is clinically effective for a variety of conditions.

Theracurmin: water-dispersible formula improves absorption

Theracurmin is another bioavailable composition of curcumin from Japan’s Theravalues Corporation. Unlike other forms of curcumin, Theracurmin is water dispersible, dissolving quickly and maintaining solubility over time. Theracurmin is a nanoparticle colloidal dispersion (sub-micron particles that are stabilized when dispersed in water). The first step is solubilizing curcumin within a vegetable gum known as ghatti. The next step is grinding the curcumin mixture using a wet-grinding mill to produce microscopic particles that are 100 times smaller than regular curcumin powder. A homogenizer then disperses these particles to create a colloidal suspension. According to the producer, the reduced particle size and improved solubility ensures that curcumin is effectively absorbed into the bloodstream.

The original Theracurmin is 10% curcumin, but newer formulations are now 30% curcumin and require only two capsules per dose rather than the six capsules required with the original formulation. One capsule of the 30% formulation typically has 300 mg of Theracurmin and 90 mg of curcumin.

According to their studies, Theravalues claims that Theracurmin is 27 times more bioavailable than standard curcumin. The company also supported an interesting human bioavailability comparison study between Theracurmin, Meriva, and BCM-95.

A variety of human clinical trials using Theracurmin show positive results for a variety of conditions and there are another 13 ongoing trials involving Theracurmin.

BCM-95: consistent bioavailability in independent comparison studies

BCM-95 is a patented formulation developed by Arjuna Natural Extracts and DolCas Biotech. DolCas Biotech specializes in “100% natural compositions,” with a focus on extraction of active ingredients without affecting their natural properties and composition.

BCM-95 features 86% curcumin blended with 7-9% turmeric essential oil (ar-turmerone from the rhizome), which naturally enhances its absorption and bioavailability. While BCM-95 doesn’t claim to have the highest bioavailability, the manufacturers’ claim of “over 6 times higher than standard curcumin” seems to have proven truthful. There are quite a few independent bioavailability studies using BCM-95 as a comparison product, and all support the manufacturers’ claim with very similar results.

Among this research, a human bioavailability study comparing a 2,000 mg dose of BCM-95 with a 2,000 mg dose of standardized curcumin had the best design, and a meaningful outcome. The researchers found that compared to the standardized curcumin, BCM-95 had better absorption, greater blood retention time (eight to 12 hours), and over six times greater bioavailability.

BCM-95 is available in various strengths. The lowest-dose capsule is 200 mg of BCM-95 containing 186 mg of curcumin. But higher dose capsules can contain up to 750 mg of BCM-95 and 500 mg of curcumin. This is the highest amount of curcumin (three to five times more) per capsule than any of the other compositions on the market, which has proven itself to be highly effective. There are over 30 published studies, including 14 human clinical trials, using BCM-95. These studies showed very positive outcomes.

There are many things to consider before choosing a product for any given patient, including purpose, acuity, and dosage—not to mention price. That’s why it’s great to have so many options when it comes to an invaluable and versatile therapeutic like curcumin.