Milk and dairy products are rich in vitamin D and calcium—substances essential for building and maintaining bones. Many people therefore say that a diet rich in dairy products can help prevent osteoporosis, a disease that is linked to both environmental and genetic factors and that causes the bones to weaken significantly with age. But a long-term study of a large number of people found that those who consistently consumed dairy products throughout the years of the study have a higher rate of bone fractures than any other participants in the study. Since bone fractures are symptomatic of osteoporosis, this study result shows that a diet rich in dairy products may actually increase, rather than decrease, the risk of osteoporosis.

Write a response in which you discuss what specific evidence is needed to evaluate the argument and explain how the evidence would weaken or strengthen the argument.