The U.S. government will sponsor a big study of fish oil and vitamin D pills to see if either supplement can keep healthy people from developing cancer, heart disease or other problems.
The study will enroll 20,000 Americans, including 5,000 blacks. People with dark skin are unable to make much vitamin D from sunlight, and researchers think this may be one reason blacks have higher rates of heart disease and cancer than whites.
The National Cancer Institute is the study's main sponsor.
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