[Slightly edited.]
I added my .02 on the matter of health care being a human and/or constitutional right here. A basic sentiment is that the Preamble of the Constitution provides a duty, particularly "general welfare," and that Art. I provides the means.* As noted here, various state constitutions speak of a comparable obligation (e.g., to care for the mentally ill), even if on their own force they do not provide self-executing commands ala the Thirteenth Amendment. This makes it comparable to a treaty without enabling legislation: a duty is set forth but the means is left somewhat open.
Treaty obligations is a suitable reference point, since the U.S. has an obligation to uphold the Universal Declaration of Human Rights, which includes:
Article 25.
* (1) Everyone has the right to a standard of living adequate for the health and well-being of himself and of his family, including food, clothing, housing and medical care and necessary social services, and the right to security in the event of unemployment, sickness, disability, widowhood, old age or other lack of livelihood in circumstances beyond his control.
* (2) Motherhood and childhood are entitled to special care and assistance. All children, whether born in or out of wedlock, shall enjoy the same social protection.
See also, here, with special reference to FN14. Marshall's dissent highlights the fact that responsibility to health care in a constitutional sense is not limited to those in governmental custody against their wills. If the government provides a benefit, it should do so equitably. In fact, this article suggests we have a property right to health care given the amount of public funding provided for medical training and research and its overall public nature in our society. As with treaties, this might be but a duty for the government to fill, one where the courts largely leave them to fill in details. Charles Black also accepted some basic rights would fit into this category. This in no way belittles the duty involved.
There are various constitutional hooks that can be provided here in additional to the duty to enforce treaties, which as noted above, is relevant here. For instance, a human right to health care might be a Ninth Amendment one, again providing authority for the government to pass legislation that does not necessarily mean the courts on their own have a duty to micromanage the details. Adequate health care, like education, might be necessary for equal citizenship; see also, privileges and immunities. Both state and federal governments would have the power (e.g., §5 of the 14A) and duty to so protect. The Due Process Clause also is a place to look, since deprivation of adequate health care can in fact lead to deprivation of life. On narrower grounds, procedural protections are also present here. But, once the government gets involved, once something is deemed "public" in nature, the procedural and substantive in particular are interlocked.
This discussion is separate from a negative right not to have the government interfere with health matters, as Justice Douglas noted: "the freedom to care for one's health and person, freedom from bodily restraint or compulsion, freedom to walk, stroll, or loaf." The Declaration of Independence says governments are created to help "secure" such rights, and this entry is largely about the affirmative duties in this respect. And, we often are told that the Constitution is about negative limitations. But, consider the Fourth Amendment which talks about right of the people to a certain degree of privacy. Is this negative only? Douglas suggested the interlocking nature of the Ninth Amendment here.
The Constitution provides for various rights that would be thin indeed with affirmative government support. For instance, trial rights -- both civil and criminal, the former a significant safeguard for a smoothly run economic system. Even if one or both parties in some fashion contributes to court costs, it is clear that the government both subsidizes it to some large extent, and provides the structure and personnel. Likewise, voting is a fundamental right. Its inherently public nature has led to the determination that political parties that provide candidates cannot discriminate by race and so forth. And, the government has a duty, in some fashion arising directly from constitutional demands, to provide voting machinery and so forth. Is health care so different?
Fact is, many basically think there is a fundamental obligation for the government to provide health care, even if they would be unclear about the specifics. It follows that government both has the duty and power to so provide. This was the mentality when FDR proposed a "Second Bill of Rights," one that included medical care. Ditto when Harry Truman proposed a national health care policy. And, it holds true up to the current day. Let's see if the duty is adequately carried out.
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* Art. I powers might also suggest federal obligations -- they were given in the first place out of a felt need for a national body to have such powers. Congress does not carry out its powers to the breadth of their possible reach -- e.g., modern federal bankruptcy law took a long time coming. But, its power to regulate interstate commerce does suggest some duty to insure problematic aspects of it are handled. This would include regulating national health care and insurance markets.