Med thumb fridge

More often than not, that 3 a.m. pizza binge is a product of too much booze, too little willpower or some combination of the two. But people with Night Eating Syndrome (NES) take nighttime eating to an extreme. They either consume a sizable chunk of their calories after dinner, or they wake up during the night to squeeze in an extra meal.

Typically, NES treatments have focused on modifying behavior or brain chemistry. But those diagnosed with NES also show altered levels of the hormones involved in regulating circadian rhythms. This, in turn, affects stress, food intake and blood sugar.

With this in mind, researchers are experimenting with chronobiological techniques to help night-eaters shift their internal clocks. In a recent study, published in the journal Psychiatry Research, psychologists from the University of Missouri-Kansas found one such chronobiological treatment, bright-light therapy, effective in curbing late-night fridge trips.

Bright-light therapy is used to treat a number of conditions in which people naturally have abnormal circadian rhythms. This may include sufferers of serious conditions such as Non-24-Hour Sleep Wake Disorder, or maybe just shift-worker who can’t maintain a regular schedule. Exposure to bright light alters hormone levels, can reduce melatonin levels and actually reset body clocks (shifting it forward or holding it back). In the case of NES, researchers used regular, repeated morning light exposure to help shift participants’ clocks ahead.

In the study, researchers ran a two-week bright-light therapy trial for 15 adults whose eating habits met the diagnostic criteria for NES. (For a minimum of three months, they got out of bed at least once a week to eat and/or regularly consumed at least 25 percent of their daily calories after dinner.) Participants spent one hour each morning staring at a 10,000-lux light box. That’s pretty bright, by the way — such boxes range in intensity from 2,500 to 10,000 lux.

After 14 days, researchers re-evaluated participants’ NES symptoms. They saw improvements in morning moods, anxiety throughout the day and, most centrally, reduced nighttime and mid-slumber snacking. Participants did not drop much weight, but that wasn’t the point. The goal is to reset fundamental eating habits.

One caveat: Though the largest of its kind so far, this study included a disproportionately high number of white women. Future research on bright-light therapy for NES would benefit from a more diverse group of participants.