On average, the more you have, the longer you will live.
UPDATE: This 2002 paper found that Medicare increased the life expectancy of older Americans:
Data on age-specific death probabilities every 10 years since 1900,
that is, before as well as after Medicare was enacted, provide an alternative
way to test for the effect of Medicare on longevity. They also provide
strong support for the hypothesis that Medicare increased the
survival rate of the elderly, by about 13 percent.