Solving the Diet-Cancer Mystery:
Scientific Studies Provide Clues
Epidemiological: Case-Control Studies
Case-control studies differ from cohort studies in that they include people who have cancer when the study starts (“cases”) who are compared to a group of people who don’t have cancer (“controls”).
Strengths of Case-Control Studies
With enough subjects in the study and careful selection of controls, case-control studies provide a cost-effective way to study cancer.
Weaknesses of Case-Control Studies
Quick: List the kinds of foods you ate most often ten years ago. Like eyewitness testimony in a courtroom, case-control studies depend on our unreliable memories. In case-control studies, cases and controls may remember their past diets differently. Some new scientific developments, such as biomarkers of dietary intake that act like fingerprints of the foods we eat regularly, can help to avoid this problem.