Delving Into The Science: Breaking Down Clinical Research
Although interfacing with clinical data can even make our heads spin at times, it’s important to have an understanding of what actually makes a good, viable study.
Measurements:
Unfortunately, many publications report the bioavailability of curcuminin without actually distinguishing between free form curcumin, curcumin metabolites, and total curcuminoids (curcumin, DMC, BDMC).
This will inevitably skew what was actually measured in sample blood, versus what is reported in the corresponding publication. Don’t forget about our little friend Beta-glucuronidase either, seeing the use of this enzyme further skews results generating false values for Free Form Curcumin. For the sake of accuracy, simple honesty, and the varying potency of each form, it is critical that all of the forms are clearly distinguished and measured correctly. These details can be confirmed in the materials and methods section of a study.
Here is a loose outline of what a curcumin study looks likes to help you imagine the process:
A set dose of a curcumin is administered to human subjects once a day.
Blood samples are collected before curcumin is
administered at very specific intervals over the course of 24 hours.
The concentrations of curcuminoids are measured
in order to plot a concentration time curve.
Results include the following:
Cmax (Concentration maximum) is when a drug reaches its peak
concentration in the blood after administration. This is depicted by the
highest point on a graph.
Tmax (Time maximum) is the time a substance
takes to reach maximum concentration.
AUC (Area Under the Curve) is the overall amount
of a therapeutic agent in the bloodstream after a dose. The AUC is dependent on
the dose and the rate of elimination from the body.
Some other
important keys to a well-designed study are: human subjects, the number of
subjects, and appropriate controlled variables.
The human league should be
the only league when it comes to study subjects. Although there is merit in
animal studies, humans are not rats, mice, or any other kind of animal. We have
entirely different anatomy, physiology, and biochemistry. Thus, data from a
different species cannot accurately show what happens within humans in all
cases. This is why healthy human volunteers are used in bioavailability studies
to increase accuracy by removing factors such as disease, medication, smoking
and other lifestyle influences.
When it
comes to sample size, the more the merrier. Although some studies with smaller
samples are still very well-designed and executed, it is even better when more
subjects are involved.
Larger
sample sizes offer higher accuracy, seeing the result is demonstrated many more
times. This is a standard that all studies should strive for.
The importance of specific scientific controlled variables is critical to a well-designed study. Unbiased studies incorporate positive and negative controls, including placebos, randomization, blind and double-blind experiments.
Figure 6. All in the Curve: Area under the plasma concentration – time curve, which depicts the exposure of the body to administered curcumin.
Making Sense of Curcumin Bioavailability Claims
This is where things can get
a little technical. Instead of hiding behind altered data and complex
arguments, let’s clarify the research associated to some of the popular curcumin
forms on the market. As mentioned, every curcumin on the market has a
bioavailability study that companies base their absorption claims on, i.e. 100x
more bioavailable.
Before comparing any two products, there are a few points to take into consideration. In general, studies investigating bioavailability of curcumin have focused on exploring the fold increase in comparison to standard Curcumin-95, which we know has very poor bioavailability. AUC (area under the curve) is considered the best method to use in any comparison.
While comparing to a standard is a good reference point, the AUC method is dose
dependent; therefore, it is not possible to conclude with any accuracy what the
effect of an increase or decrease in dose will have on the AUC.
Again, many publications report the bioavailability of curcuminin without actually distinguishing between free form curcumin, curcumin metabolites, and total curcuminoids (curcumin, DMC, BDMC). However, in Schiborr et al., (2014), each individual curcuminoid (curcumin, DMC, BDMC) was investigated separately. Using this same methodology, Kumar et al., (2016), highlight that CurQfen is 270x higher than standard curcumin.
Figure 7. A plotted graph: Comparison of free form curcumin plasma concentration if various curcumin formulations. Using accurate experimental methodology, the above data shows the concentration-time-point curve for major curcumin formulas, measuring the levels of free form curcumin. A comparison of the area under the curve (AUC) for CurQfen® and Longvida® reveals that CurQfen® is 6.7X more bioavailable Longvida® at equivalent doses. Because correct adjustments are used, levels of free from curcumin for other formulations are difficult to detect.
The scientific community has known for some time that different people respond differently than others to similar environments, and this is also the case with nutrition. After all, we’ve all heard a friend say that a particular diet worked wonders for them, but when we try the same program, we don’t see the same success. Wouldn’t it be great if there were a way to know whether your genetic blueprint was compatible with a particular diet or exercise regimen? Or whether you have specific sensitivities to certain foods? And what if you could understand your genetic susceptibility to stress or
Theracurmin™ is a nanosized curcumin formula made from a mixture of micronized curcumin and gum ghatti solution. Theracurmin’s particle size is reduced via a wet mill grinding process and then dispersed using a high-pressure blending technique. This creates a colloidal suspension that is highly water soluble. BCM-95® is a patented curcumin formula that combines curcumin and volatile agents in turmeric essential oil to increase bioavailability. The formula is also comprised of lecithin and medium chain triglycerides to further assist in this process. Turmeric essential oil constitutes approximately 9% of the formulation. Meriva® uses micelle technology to create a patented Phytosome®
Magnesium Hydroxide: This form is often used as an antacid and/or in laxatives. It can be found in over-the-counter products, such as milk of magnesia. Because It has poor bioavailability, it is considered one of the least optimal forms to use as a supplement. Magnesium Oxide: This form of magnesium is one of the most commonly used in supplements. It is desirable because it is inexpensive and the compound is very small, so large amounts of elemental magnesium can be delivered without taking up much space in a tablet or capsule. Magnesium oxide has long been considered a poor source of magnesium,