Opposite of Hypochondria

I was recently trying to think of a pithy term for the opposite or inverse of hypochondria, i.e. a condition in which one might willfully ignore symptoms of sickness or delusionally believe one is perfectly healthy. The term "hyperchondria" occurred to me, and indeed it appears in some blogs and an online urban dictionary, but it didn't feel right. For "hyperchondia" to make linguistic or philological sense here, "chondria" would have to mean something like health (or even belief in health). Otherwise, it's like taking the word "alcoholic" (addicted to alcohol) and creating the word "workaholic" - which technically should mean "addicted to workahol".
Sure enough, when I found etymology of hypochondia / hypochondriac online, it did not support creation of hyperchondriac for this purpose:

hypochondriac (adj.)
1590s, "pertaining to the hypochondria," also "afflicted with melancholy," from Fr. hypocondriaque (16c.), from M.L. hypochondriacus, from Gk. hypokhondriakos "pertaining to the upper abdomen," from hypokhondria (see hypochondria). The noun is from 1630s, "melancholy person;" in the modern sense from 1888.
hypochondriasis
1766, from hypochondria + an unusual use of -osis.
hypochondria
1839, "illness without a specific cause," earlier (1660s) "depression or melancholy without real cause," earlier still (late 14c.) ipocondrie "upper abdomen," from L.L. hypochondria "the abdomen," from Gk. hypokhondria (neuter plural of hypokhondrios), from hypo- "under" (see sub-) + khondros "cartilage" (of the breastbone). Reflecting ancient belief that the viscera of the hypochondria were the seat of melancholy and the source of the vapors that caused such feelings.

Source: http://www.etymonline.com
But then I suddenly grew curious about this meaning of "chondria" - why should there be a reference to the abdomen in "mitochondria" and what could it possibly mean? Of course, I'd forgotten that mitochondrion is the singular, so the origin of the "ia" ending is due merely to pluralization. Still, it was interesting to see the very different origin which resulted in a facially similar English word:

mitochondria
1901, from Ger., coined 1898 by microbiologist Carl Benda (1857-1933), from Gk. mitos "thread" (see mitre) + khondrion "little granule," dim. of khondros "granule, lump of salt."
mitochondrion
singular of mitochondria.

Source: http://www.etymonline.com
So this is pretty cool and I get to think of myself as a mini-Tolkien for a few minutes.