Eating food late at night contributes to tooth loss, regardless of the type of food you eat, according to American and Danish researchers, who noted the reason could be that saliva flow, which is important for removing debris in the mouth, dries up at night.

You can read about the study, by researchers at the University of Missouri-Kansas City, and Copenhagen University, in the August print issue of Eating Behaviors, which is already available online.

For the study, the researchers examined data on 2,217 men and women aged 30 to 60, who were taking part in the Danish arm of a World Health Organization medical study known as MONICA (MONItoring trends and determinants of CArdiovascular disease).

They assessed the participants’ oral health, eating behavior, general health and other characteristics at two points in the study: 1987/88 and again in 1993/94.

They found that 8 per cent (173 subjects) were classed as nocturnal eaters, that is they consumed a quarter or more of their daily calories after their evening meal, and would wake and have a snack in the middle of the night at least twice a week.

They also found, even after taking into account potential influencing factors like age, smoking status, and how much sugar or carbohydrate there was in their diet, the nocturnal eaters had lost more teeth at the later point in the study than the non-nocturnal eaters.

The researchers concluded that:

” In sum, nocturnal eating contributes to tooth loss.”

They recommended that dentists and oral treatment providers encourage their patients to practice good oral health and be aware of the impact nocturnal eating can have on the health of their teeth.

They suggested, for instance, that practitioners screen patients for nocturnal eating.

A scientific adviser to the British Dental Association, Professor Damien Walmsley, told the BBC that eating at night when there is less saliva, and food debris tends to linger longer, boosts the effect of consuming sugary and acidic food and drinks.

He said it was important to brush teeth twice a day with fluoride toothpaste, and one of these brushing sessions should be just before going to bed, and also:

“Where possible, consume only water for at least an hour before the final brush of the day,” said Walmsley.

“Nocturnal eating predicts tooth loss among adults: Results from the Danish MONICA study.”
Jennifer D Lundgren, Karen B Williams, and Berit L Heitmann.
Eating Behaviors, Volume 11, Issue 3, August 2010, Pages 170-174

Additional source: BBC.

Written by: Catharine Paddock, PhD