People who tend to eat a quarter or more of their daily calories after dinner by taking a midnight snack several times a week may not only be increasing the size of their waists, but also affecting their dental health, according to Danish researchers.

A study of the records of more than 2,200 adults, aged 30 to 60 years, who participated in a Danish medical study, were evaluated at two different times, over a period of six years. Only 8 percent of the participants, 173 in all, were diagnosed as nighttime eaters, people who ate at least a quarter of their daily calories at dinner each day and reported waking up at midnight to eat a snack at least twice a day.

By tracking participants ‘records, researchers found that night eaters lost more teeth during the six-year period, even when taking into account participants’ ages, diabetic status, smoking status, body mass index and the consumption of sugars and carbohydrates. People who did not eat at night, who were not diabetic and who did not smoke had significantly lower levels of tooth loss.

The researchers theorized that, since people produce less saliva at night, night eaters may not have enough saliva to remove food waste from their mouths. They recommend that dentists and patients discuss nocturnal eating behaviors and that patient’s brush each night after eating to help preserve their teeth.