The OP provided a link that doesn't go to an Elsevier-affiliated website.
Elsevier is an academic publisher that is a relic of a pre-digital world. Essentially, it leeches on universities, charging money for access created by academics,funded by the state, and peer-reviewed by volunteers for free. They justify their need to charge money by reasons such as hosting costs, but whenever someone tries to host their articles for free, they pull out the big guns.
Such actions, in particular, led to death Aaron Schwartz (see https://en.wikipedia.org/wiki/Aaron_Swartz ).
Elsevier is not liked around here.
Speaking of resources that anger Elsevier by hosting articles for free, Sci-Hub is one. In particular, you can read the full text of the article by going to https://sci-hub.cc/ and looking up the paper's DOI (10.1053/j.gastro.2017.10.040).
This full text is not available for free on the original publication link (nor on the NIH website). The study was funded by: the Extra Foundation Health and Rehabilitation, the Norwegian Celiac Association, the Throne Holst Foundation for Nutrition Research and the Wedel Jarlsberg Foundation - neither entity being Elsevier. (You can find this in the paper once you pay Elsevier to access it).
So yes. Oh, Elsevier.
