Your heart has taste buds that can sense the flavor of food. Nobody is quite sure why evolution brought such an odd result, but it did. We know that, but we don’t know why, although there are some good guesses.

by David Stone

Assorted Ideas, Large & Small

It is one of nature’s strangest and most enduring mysteries. Why do we have taste buds in our hearts?

Surprisingly, your heart contains the type of receptor responsible for tasting bitter substances. Researchers believe this could be linked to sensing potentially toxic compounds in the bloodstream.

But what is not clear is why these heart-borne taste buds exist at all. Several theories are taking a shot at why they do.

One suggestion is that the receptors act like ‘flavor enhancers’ to make the rich array of bitter molecules produced by our bodies into something more palatable. But this has never been proven.

Another theory is that they are there to help the heart sense the composition of blood, so it can regulate its rate accordingly. But if this were true, one would expect taste receptors throughout the rest of our vascular system.

But we know of no evidence that the heart ‘tastes’ what’s in the blood. It’s a total mystery.

The heart is one of only a few human organs to contain more than one type of receptor – and the tastebuds in your heart are very similar to those found on the tongue.

There are at least five groups of heart taste receptors, two of which have been partially characterized.

They are called hTAS2R38 and hTAS2R43 – TAS stands for Taste Associated Specialised Receptor.  

These receptors contain a cluster of proteins that act in a similar way to the sensory system in our mouths, which detects sweet, sour, salty, bitter and umami (savory) tastes.

Still, several pieces of evidence point in new directions. For one thing, it remains unclear how anything could get in – or out – of the heart’s taste receptors to stimulate them.

Also, if this actually happens, you would expect the cells to be clustered in patches, like those found on the tongue. Instead, they are distributed randomly throughout heart muscle tissue.

Researchers have known about these receptors for a while but haven’t been able to understand their biology. Now that we know what they look like and how they work, researchers can start working on ways of modifying them as drug targets.

Whatever their role turns out to be, taste receptors could one day help scientists develop new medicines for controlling high blood pressure and other types of cardiovascular disease – which would potentially offer a much more natural way of controlling such conditions.

Our taste buds found in other unexpected places?

Yes, taste receptors are found throughout the body. In addition to the heart, they are also found in the lungs, kidneys, and gut. But their role is so unclear, any explanation is not much more than guessing. They may be just evolutionary debris left behind as a more complex animal developed.

People with specific types of bitter taste receptors might be more prone to certain diseases like lung cancer, kidney stones, and obesity.

So scientists are trying to figure out if they play a role in these conditions, and if so, can they help create new treatments?