A person could eat 8 to 10 pounds of potatoes a day, with some milk or cheese, and be very healthy. Soon, potatoes became the main food in Ireland. Then, in 1845, a disease killed all the potatoes in Ireland. Two million people died of hunger. Many Irish who did not die came to the United States at this time. Over million Irish came to America; one of them was the great-grandfather of John F. Kennedy. In other parts of Europe, people did not want to change their old food habits. Some preferred to die of hunger rather than eat potatoes.