Finding background information in a specialzed reference work at the beginning of your research is especially important if you are unfamiliar with the subject area, need to focus or narrow your topic or are not sure from what angle to approach your research.
Specialized dictionaries, encyclopedias or handbooks can provide:
PENNutrition: Practice-based Evidence in Nutrition (PEN) PENNutrition is a database developed by Dietitians of Canada containing evidence-based guidance on food and nutrition. With tools and resources, it supports decision-making for a broad spectrum of practice in nutrition and dietetics.