The information has been confusing. Many weight loss gurus have warned against eating after 7 in the evening.  Many other experts have said “calories are calories,” no matter when you eat them. Now, a few studies have shown that eating schedules do matter.  One conducted at Northwestern University, found that “eating at the ‘wrong’ time leads to more than twice as much weight gain, even when the overall calories consumed are the same as those eaten at appropriate times.” Yes, the experiment was conducted with mice, but the lead author of the study speculates that it’s due to “the interplay between body temperature, metabolic hormones such as leptin, and the sleep-wake cycle.

For humans, nighttime is a time for rest, as the body temperature declines, she says. ‘Eating at night is contradicting your body’s natural circadian rhythm,’ she says. ‘The leptin levels are starting to rise, and are supposed to be discouraging you from eating.’ Rising leptin levels suppress appetite.” (More at MedicineNet.com )

At the end of a 3 ½ year study with humans, published in The American Journal of Clinical Nutrition, a group of night eaters gained 13.6 pounds while the non-night eaters gained only 3.7 pounds .

Besides the metabolic factors that need further exploration, we know that when we are tired, we are less likely to make healthy choices. What pulls us to the refrigerator late at night? Vegetables and fresh salads? Probably not.