The Nutrition Evidence Library (NEL) collaborates with stakeholders and leading scientists to conduct a wide range of systematic review projects to inform federal nutrition policy and programs. The systematic review process used by the NEL seeks to objectively gather, organize, evaluate, describe, and synthesize research to answer important food- and nutrition-related questions. These systematic reviews are fully documented and available on the USDA Nutrition Evidence Library (NEL) website ( The website facilitates transparency of the complete body of scientific evidence used and key decisions made throughout the systematic review process. USDA, as well as other federal agencies and stakeholders, leverage these trustworthy systematic reviews when making key decisions that influence nutrition policy, dietary guidance, nutrition education, and communication efforts. NEL systematic reviews also identify research gaps and describe what research is needed to better inform future recommendations and policy.