condition. As mentioned earlier, this variable is endogenous. Possible instruments could include
whether any blood relatives had been diagnosed with any related health problems. A blood
relative’s health is most arguably an exogenous variable; we have very little control over whether
or not a grandparent had a heart condition. It may also be highly correlated with our own health
and level of health information; our family’s health history is a strong predictor of our own
health and watching a family member struggle with ill health may provide motivation to adopt
healthier practices.
Prices of medication could also serve as additional instruments (Park and Davis, 2001). Due to
data limitations, however, we simply use whether or not an individual currently has health
insurance as proxies for prices. Additionally, having health insurance should also increase the
probability that an individual is aware of his or her health condition. Finally, we use whether or
not an individual was diagnosed with diabetes as an adolescent or younger (age 18 or below).
This is meant to be a proxy, albeit imperfect, for whether or not an individual has Type I or Type
II diabetes. Individuals with Type I (also called juvenile diabetes) almost always need to take
insulin while individuals with Type II (or adult on-set diabetes) can often manage their
symptoms through lifestyle changes alone.
Results
Results of the treatment effects estimations are presented in Tables 2. Looking across the intake
and other behavior equations, the sign pattern on the variable labeled “diabetic” suggests that
people do respond to being told they are diabetic. For those told they are diabetic, signs are
negative for intake of all foods and nutrients: starches, milk, meat, fat, sugar, vegetables, fruit,
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