Final answer:
Nina can safely consume 18.89 cans of diet soda sweetened with aspartame each day.
Step-by-step explanation:
According to the Acceptable Daily Intake (ADI) set by the Food and Drug Administration (FDA), the safe amount of aspartame that Nina can consume daily is 50 milligrams per kilogram of body weight. Since Nina weighs 150 pounds (approximately 68 kilograms), she can safely consume 3,400 milligrams (or 3.4 grams) of aspartame daily.
Now let's calculate how many cans of soft drinks Nina can have.
According to the American Journal of Preventive Medicine, the average aspartame content in diet soda is 180 milligrams per 12-ounce can. So, if each can contains 180 milligrams, Nina can safely consume 18.89 cans of diet soda each day.