Is Chocolate A Food? A Problem In PubMed

By Eric Rumsey and Janna Lawrence

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

As we’ve written, searching for food-related subjects in PubMed is difficult because of the way the MeSH system is organized. Plant-based foods are especially difficult because in most cases they are treated mainly as plants rather than food.

One result of treating plant-based foods as plants is that the MeSH term is usually the botanical plant name; in the case of chocolate it’s Cacao. This is usually not a serious problem when searching for specific substances because the common food name maps to the botanical MeSH term.

A more serious consequence of treating plant-based foods as plants instead of foods is that they are usually not in any food-related explosion, but only in the Plants explosion. So the only occurrence of chocolate (Cacao) is here:

Plants
   Angiosperms
      Sterculiaceae
         Cacao

The reason this is a problem is because articles on chocolate/Cacao will not be retrieved in a search for Food. So, for example, if you do a general search for food-related causes of migraine, you will not retrieve this article:

Chocolate is a migraine-provoking agent
Journal: Cephalalgia
http://www.ncbi.nlm.nih.gov/pubmed/1860135

This is not retrieved by searching for food because Cacao is not in the Food explosion. More broadly, however, it’s also not retrieved with the comprehensive Food-Diet-Nutrition hedge that we’ve discussed previously, which includes text-words as well MeSH terms and explosions.

Here are several other articles on health and medical aspects of chocolate that are not retrieved by our broad Food-Diet-Nutrition hedge:

If chocolate were the only case of a plant-based food that is not retrieved in a broad PubMed search for food-related topics, it would be a trivial matter. But that’s far from being the case. There are many plant-based foods that have the same problem in PubMed. We will be writing on several of these foods in the next few months, so keep an eye on this space!