Reading an NYT essay http://www.nytimes.com/2013/10/20/opinion/sunday/why-we-make-bad-decisions.html about "Why We Make Bad Decisions", in which Noreena Hertz describes her search for treatment for a mysterious ailment, I was struck by this passage:

Quote
If we are to control our own destinies, we have to switch our brains back on and come to our medical consultations with plenty of research done, able to use the relevant jargon. If we can’t do this ourselves we need to identify someone in our social or family network who can do so on our behalf.
This kind of research is g-loaded, and people who cannot do it are less likely to know people who can (with the caveat that elderly people with declining cognitive function may well have children who are sharp). I don't think there is a simple solution to this problem. Higher-IQ people are also more likely to have health insurance.

Hertz recently wrote a book "Eyes Wide Open: How to Make Smart Decisions in a Confusing World".

A paper "Intelligence Predicts Health and Longevity, but Why?"
by Gottfredson and Deary http://67.208.89.102/files/2006/02/22/20060131_GottfredsonIntelligence.pdf also finds that self-care is g-loaded.

Quote
Large epidemiological studies of almost an entire population in Scotland have found that intelligence (as measured by an IQ-type test) in childhood predicts substantial differences in adult morbidity and mortality, including deaths from cancers and cardiovascular diseases. These relations remain significant after controlling for socioeconomic variables. One possible, partial explanation of these results is that intelligence enhances individuals' care of their own health because it represents learning, reasoning, and problem-solving skills useful in preventing chronic disease and accidental injury and in adhering to complex treatment regimens.