An article published in the Atlanta Journal-Constitution included good news and bad news: "The good news is that a
Southern diet is delicious and makes us happy. The bad news is that it might raise the risk of our dying early." This statement was based on an observational study of more than 21,000 people ages 45 and older that included 10 years of follow-up. The study found that "participants who ate a Southern-style diet most regularly had a 46% higher risk of sudden cardiac death than people who had the least adherence to this dietary pattern." Based on this study, is it reasonable to conclude that a Southern-style diet causes higher rates of cardiac death? Explain why or why not.

(a) No, it not a reasonable conclusion because cause-and-effect conclusions cannot be drawn from an
observational study.
(b) Yes, it is a reasonable conclusion because a 46% increase is a large enough effect that it must be related
at least partially to diet.
(c) No, it not a reasonable conclusion because sudden cardiac events are not the only cause of early death.
(d) Yes, it is a reasonable conclusion because the 10 year follow-up allows us to make valid comparisons of the
effects of different diets.