Just like approximately 5% of the spice turmeric is composed of an active compound called curcumin, about 5% of black pepper by weight is this compound called piperine. Curcumin is responsible for the yellow color of turmeric and piperine for the pungent flavor of pepper. Piperine is a potent inhibitor of drug metabolism. One of the ways our liver gets rid of foreign substances is making them water soluble so they can be more easily excreted. But this black pepper molecule inhibits that process.
And it doesn’t take much. If people are given a bunch of turmeric curcumin, within an hour there’s a little bump in the level in their blood stream. We don’t see a large increase because our liver is actively trying to get rid of it. But what if the process is suppressed by taking just a quarter teaspoon’s worth of black pepper? Then you see curcumin levels skyrocket. The same amount of curcumin consumed, but the bioavailability is up 2000%. Even just a little pinch of pepper—1/20th of a teaspoon—can significantly boost levels. And guess what a common ingredient in curry powder is besides turmeric? Black pepper.
Another way to boost the absorption of curcumin is to consume it in the whole food, turmeric root (fresh or dried as a powder) because natural oils found in turmeric root and turmeric powder can add to the bioavailability of curcumin seven to eight fold. When eaten with fat, curcumin can be directly absorbed into the bloodstream through the lymphatic system thereby in part bypassing the liver.
How is it prepared in India? With fat and black pepper.