It’s a commonly held suspicion that eating after a certain time in the evening – say 7 or 8 p.m. — will cause a person to gain weight. But is it true?
The answer is: yes and no.
If the simple act of eating late in the day caused weight gain, everyone in Spain would be obese, since the traditional dinner time in that country is 9 p.m. or later. But food has no more calories at 9 p.m. than it does at 6 p.m. A 600-calorie meal is 600 calories no matter what time it is consumed.
So, maybe, it’s not when you eat, but what you eat and how much. According to the U.S. Department of Agriculture’s Weight Control Information Network web site, “it does not matter what time of day you eat. It is what and how much you eat and how much physical activity you do during the whole day that determines whether you gain, lose, or maintain your weight.” A 2005 study of primates at Oregon Health & Science University confirmed that statement, finding late-night meals did not lead to extra weight gain; whether consumed at 10 a.m. or 10 p.m., a calorie was just a calorie.
On the other hand, in a study of adult men and women, published in April 2011 in the journal Obesity, scientists discovered eating after 8 p.m. was associated with a higher body mass index, suggesting late-evening calories are, for some reason, more hazardous to one’s weight.
In general, the lateness of the hour can inspire us to eat the wrong things (fast food places are open late, farmers’ markets are not) and eat too much because we are mindlessly munching, usually while distracted by the TV.
Diet books, programs, and dietitians generally recommend not eating after dinner unless we choose a small, calorie-controlled snack to combat actual feelings of hunger. It’s just too easy to lose control with mindless snacking in the evening and undo all progress from healthy eating and exercising accomplished earlier in the day.
Another way late-day eating can quickly go off the rails is when accompanied by alcoholic beverages. Not only does alcohol cut down our inhibitions, allowing us to talk ourselves into “just one more” handful of chips or cookies, alcoholic beverages themselves can be loaded with calories.
As with most health and weight loss questions, it seems the best answer for now is, “everything in moderation.” If you are truly hungry between dinner and bedtime, a small, reasonably portioned snack seems unlikely to cause significant weight gain. It’s what you consume all day, every day that changes the numbers on the scale.