People with coeliac disease can kiss people who have eaten gluten without worry, according to a new study, as researchers found only negligible traces of the protein were transferred.
Approximately one per cent of the population is impacted by the autoimmune disorder, which can cause severe abdominal pain, indigestion and diarrhoea if wheat, barley or rye is consumed.
Even without immediate symptoms, gluten ingestion can cause intestinal damage for people with coeliac disease, which can create anxiety around consuming even the smallest amounts, such as through kissing after eating dinner or drinking beer.
Anne Lee, PhD, assistant professor of nutritional medicine at Columbia University, said her previous research showed concerns around social interactions for those with coeliac disease had taken its toll on their quality of life.
She said: “Everyone worries about whether gluten is getting into their food at a restaurant, but no one really looked at what happens when you kiss afterwards. The advice we gave about kissing and coeliac disease was based on precaution and assumptions. We were using our best judgment. I felt it was important to do research to see if there was any actual risk."
Researchers recruited ten couples, each where one partner had coeliac disease, for a two-part study. In each session, the non-coeliac partner ate ten saltine crackers and the couple kissed for ten seconds.
In one session, the partners waited five minutes before the kiss, and in the other, they drank four ounces of water before kissing. In both situations, researchers found that the gluten transfer, which was measured in the saliva of the partner with coeliac disease, was minimal in the majority of participants.
While gluten was still found in saliva after kissing a partner who had consumed gluten and then had a glass of water, in almost all cases the amount was less than 20 parts per million -the level allowed in gluten-free products which is considered safe. There was only one kiss from a partner with unusually high saliva gluten levels, which led to a positive gluten test in urine but no symptoms were reported.
“For clinicians, we can now say to patients, ‘You don’t have to go to extreme measures,’” Dr Lee said. “Patients with coeliac disease can be more relaxed, knowing that the risk of gluten cross-contact through kissing a partner who has consumed gluten can be brought down to safe levels if food is followed by a small glass of water.”
