Is There Gluten In Envelope Glue?

Portrait of woman with blonde bob licking envelope
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There is no gluten in envelope glue, according to the International Envelope Manufacturers Association, which represents makers of envelopes and provides public education about envelope making. 

The association's website lists "Is there gluten in envelope adhesives?" as a Frequently Asked Question, and says in answer: "Remoistenable adhesives are derived from corn starch and do not contain wheat or rye gluten."

Furthermore, in the Fall 2007 issue of Gluten Free Living, Amy Ratner reported, "There are actually only a few envelope glue manufacturers in the United States. National Starch & Chemical, a New Jersey company, is one of the largest adhesive suppliers in the world. A company spokesperson says it makes its glue from corn, which is gluten free."

However, another source contradicts this information about the source of envelope glue. Dr. Thomas Connelly, a dentist who writes for the Huffington Post, reports that most envelope glue isn't made from corn. Instead, Dr. Connelly states, the glue is made from gum arabic, which is a type of hardened tree sap that comes from the acacia tree. Acacia trees are grown in Africa and India.

Now, both corn and gum arabic are considered gluten-free (assuming they're not produced in a way that introduces gluten cross-contamination, of course).

But you might want to consider this: Dr. Connelly questions whether envelope factories (which, after all, are not food factories) are clean and sanitary enough generally.

He doesn't mention celiac disease or non-celiac gluten sensitivity, of course, and he doesn't raise any possibility of getting glutened from an envelope...but he doesn't recommend licking envelopes, either.

Now, no one (including Dr. Connelly) is arguing that envelope glue is toxic. (Remember that classic Seinfeld episode, where George's fiance, Susan, died from licking the envelopes for their wedding invitations?

 That wasn't real.) But even though envelope glue doesn't seem to include any gluten ingredients, you may have reasons for avoiding it. It tastes nasty, for one.

Fortunately, self-adhesive envelopes are readily available at office supply stores, although I find the glue on them a bit wimpy — the envelopes don't always stay sealed, and that's just on the way to my local post office, so I worry that they'll pop open en route to their final destination.

However, that's an easily solved problem: just use a little bit of tape on the flap, or (if you want to be thorough) seal the envelope with a glue stick.

As for stamps, a Post Office spokesman told Ratner there's no gluten in stamp glue either. At any rate, the ingredients in stamp adhesives are much less of an issue, since the vast majority of stamps now have pressure adhesive glue and can be pressed onto your mail without the need to lick them.