Though it is not a formalized entry into in our criminal or civil law code, the United States was FOUNDED on the notion that all peoples are entitled to the rights of 'life, liberty and the pursuit of happiness'.
By extension, the right to life would seem to naturally imply the 'right to healthcare', as healthcare is, or can be, a necessary element in maintaining human life.
In other words, though there is nothing in the U.S. Constitution that makes LEGAL and BINDING Jefferson's philosophical proposition regarding our inherent human rights, it is a conceptual foundation that supposedly frames our very purpose and reason for existing as a nation, as a common people. We were literally designed as a state to be the guarantor of HUMAN RIGHTS that other failing and flawed political systems had denied to their citizens.
However, all that being said, there is really NO SUCH THING AS INHERENT HUMAN RIGHTS. There is only a compact that exists between humans and the forces that govern them. That is called the LAW. The LAW can be amended or revoked at anytime, and what we once held in compact with the state, the state can duly or unduly change.
That is why, like Spiderman, I operate outside the law. I expect no free healthcare for I pay no taxes, or at least as little as I can get away with. And furthermore, I refuse to stop at red lights if there are no cars to bar my passing. I am a rebel. I am a man without a country . . . but I do have one helluva heath insurance plan, so ehhh, what do I care.
(the last paragraph above is pure comedy and not to be taken seriously . . . not good comedy, but still not to be taken seriously, nonetheless)