Individuals with celiac disease may experience more than just butterflies in their stomachs when it comes to kissing. The concern of unintentionally consuming gluten through a kiss was a genuine worry for many participants in a recent study published in the journal Digestive Disease and Science.
Nevertheless, a new study offers reassuring findings. Data from a small study set to be presented at Digestive Disease Week 2025 in San Diego, California suggests that gluten cannot be transmitted through a kiss, even if one partner has recently consumed a gluten-rich snack.
Anne Lee, co-author of the study and assistant professor of nutritional medicine at Columbia University, explained, “Everyone worries about gluten contamination in their food at a restaurant, but the impact of kissing afterwards had not been thoroughly investigated. The advice previously given regarding kissing and celiac disease was precautionary. We wanted to conduct research to determine if there was a genuine risk.”
Celiac disease is an autoimmune condition where the body cannot tolerate gluten, a protein found in wheat, barley, and rye. Gluten is present in various foods such as pasta, bread, and granola, and contributes to food structure. Celiac disease affects approximately one percent of the population, with around 2 million Americans diagnosed. Symptoms of celiac disease include digestive discomfort such as abdominal pain, indigestion, and diarrhea. Ingesting gluten can lead to intestinal damage for those with celiac disease, even in the absence of immediate symptoms.
To explore the potential transfer of gluten through kissing, researchers at Columbia University enlisted 10 couples for a two-part study. One partner had celiac disease while the other did not. In each session, the non-celiac partner consumed 10 saltine crackers before sharing a 10-second kiss. In one session, there was a five-minute interval before the kiss, while in the other, both partners drank four ounces of water before kissing.
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Gluten transfer was analyzed in both scenarios by examining the partner with celiac disease. The majority of participants exhibited minimal gluten transfer in both situations. Although gluten was detected in saliva after kissing a partner who had eaten saltines and then drank water, the concentration was consistently less than 20 parts per million. This level is considered safe and falls within the permissible range in many gluten-free products.
Lee remarked, “This study allows clinicians to reassure patients that extreme measures are unnecessary. Individuals with celiac disease can now feel more at ease, knowing that the risk of gluten cross-contact through kissing a partner who consumed gluten can be minimized to safe levels by following up with a small glass of water.”
While individuals with severe allergies to peanuts or shellfish should still exercise caution before kissing due to the potential for allergen exposure through saliva.
The findings of this study are currently pending peer review. Digestive Disease Week serves as a premier gathering of medical professionals, researchers, and scholars in the fields of gastroenterology, hepatology, endoscopy, and gastrointestinal surgery worldwide.