Turmeric and its active components, curcumin and curcuminoids, are fascinating . . . and widely misunderstood.
There are oodles of fascinating observations detailing curcumin’s potentially beneficial effects in experimental preparations, effects that likely originate with its anti-oxidative and anti-inflammatory effects, perhaps even an anti-aging/longevity effect and protection against neurodegerative diseases such as Alzheimer’s dementia and Parkinson’s disease.
But there’s a hitch in all these observations: There is nearly zero absorption of curcumin from the intestinal tract upon oral ingestion, with even less reaching the brain through the blood-brain barrier to exert beneficial effects for neurodegenerative disease. In other words, take, say, 600 mg of concentrated curcumin and virtually none is actually absorbed to yield anti-inflammatory or other benefits in joints, brain, or liver, as nearly all of it passing out into the toilet in bowel movements. The great bulk of evidence describing the effects occur without substantial absorption. Given the considerable benefits observed in various experimental preparations, the lack of intestinal absorption has therefore spawned efforts to increase absorption such as adding piperine, bioperine, and even phytosomal and nanoparticle preparations.
Despite the lack of absorption, the evidence underlying curcumin’s benefits in humans, not experimental models, is solid with benefits that include:
- Reduction of joint pain in people with osteoarthritis
- Reduction of inflammatory blood markers such as tumor necrosis factor
- Reduced likelihood of progression of pre-diabetes to type 2 diabetes and improved insulin sensitivity
In other words, despite lack of absorption, curcumin does indeed appear to provide benefit. But why and how?
I believe it is becoming clearer and clearer that the bulk of curcumin’s beneficial effects are due to intestinal effects such as suppression of fungal overgrowth, effects on bacterial species (e.g., marked reduction in Ruminococcus, Blautia, and many species that are over-represented in SIBO; increased Bacteroides) and perhaps direct effects on the intestinal lining that includes reduction of abnormal intestinal permeability, strengthening of the mucous defensive barrier, and reduced entry of bacterial lipopolysaccharide into the bloodstream. Curcumin has been shown to have beneficial effects on overall bowel flora composition that includes increased bacterial species diversity. Emerging evidence also suggests that curcumin possesses prebiotic fiber properties, also, an effect that may achieve such benefits as strengthening of the mucous barrier. The most important effect of all, however, may be the strengthening of the intestinal barrier and reduced LPS, effects that would explain curcumin’s effects on reducing body-wide inflammation.
Because turmeric contains only 2-5% curcumin, the benefits are enhanced by taking a supplement that has higher curcumin content. Some brands, for instance, have 90% or more curcumin. It has become clear that concentrated turmeric exerts greater effects than turmeric with only 2-6% curcumin.
My point in all this? If you take turmeric for, say, joint pain or other issue and experience benefit, it is likely that you are not directly reducing inflammation in the joint, but have altered bowel flora and the mucous lining of the intestinal tract in positive ways. In other words, you have at least partially addressed the dysbiosis (SIBO?) that was contributing to joint inflammation and should consider further efforts to cultivate healthy bowel flora and strengthen the mucous lining. The reduction you may experience in joint inflammation also reflects just how powerful intestinal dysbiosis and higher LPS levels can be in “exporting” inflammation to other parts of the body outside of the intestines.