PubMed Food Problem: Cranberry & Cranberries

By Eric Rumsey and Janna Lawrence

[Check out additional articles on PubMed & Plant-Based Foods]

Part of the problem in searching for food in PubMed is that it’s often the case that there’s a fuzzy border between between food and medicine.   A food that is enjoyed for its taste and general nutritional benefits may have properties that make it therapeutic for specific health conditions. A good example of this is cranberries, and cranberry juice, which may have benefits for prevention of urinary tract infections.

As with most plant-based foods, in MeSH indexing, cranberry is in the Plants explosion, and it’s not in any food, diet or nutrition (FDN) explosion. Fortunately, most articles on cranberries and cranberry juice are assigned some FDN indexing terms so that they are retrieved in broad FDN searches. Articles on cranberry juice are often under Beverages, and some articles on cranberries are under Fruit or Dietary supplements.

To show how this works in PubMed, we searched for cranberry or cranberries in the article title, limited to human, and retrieved 322 articles. We then combined this with our broad hedge search to get all articles that contain food, diet or nutrition MeSH terms or text words. This retrieved 255 articles — 79% of the cranberry/cranberries articles, which is a fairly good retrieval. But still, it’s certainly notable that there are 67 articles that are not retrieved, many of which appear to be very much on target, that don’t contain any FDN MeSH terms or text words. Here are some examples:

As we mentioned above, plant-based foods are tricky to search in PubMed because the name of the food plant is usually only in Plants, and not in any FDN explosion. The five articles above are all indexed under Vaccinium macrocarpon, the taxonomic name of cranberry, which is in the Plants explosion. So if you were searching for articles on urinary tract infections and plant-based foods, a strategy that would retrieve these articles would be to combine Urinary Tract Infections AND Plants.