Maybe. Remember that the D&C 89 was prefaced with:
To be sent greeting; not by commandment or constraint, but by revelation and the word of wisdom, showing forth the order and will of God in the temporal salvation of all saints in the last days—
Given for a principle with promise, adapted to the capacity of the weak and the weakest of all saints, who are or can be called saints.
In since the late 1800s, the principles contained in D&C 89 have been codified by various statements of prophets. Some have clarified it, for example hot drinks being tea and coffee, and others have added to it Word of Wisdom, for example illegal drugs.
While D&C 89 is referenced during any discussion of the commandments of health, they are not exactly the same.
Wheat consumption is not a strict part of the Lord's law of health; i.e., one that precludes good standing in the Church. Perhaps a gluten-free diet is a "minor" sin; we can't really say. Many commandments are intentionally left to personal revelation.
And finally, I cannot tell you all the things whereby ye may commit sin; for there are divers ways and means, even so many that I cannot number them.
John Taylor quoted Joseph Smith as describing his method of governance:
I teach them correct principles, and they govern themselves.
In summary, D&C 89 suggests eating wheat; the Word of Wisdom does not require it.
FYI, in additional to celiac disease, there is non-celiac gluten sensitivity. It can happen at any severity, and diagnosis is really only possible after comparing gluten and non-gluten diets. Individual circumstance make a difference.
And see that all these things are done in wisdom and order; for it is not requisite that a man should run faster than he has strength.