Skipping Meals to Lose Weight? Not so Fast!

Many of us have skipped a meal here or there to make sure we’re at our slimmest for a special occasion or to squeeze in to a particularly form-fitting outfit. Nationwide, about 15 percent of adults say they have fasted to slim down, and many popular diets even encourage intermittent fasting as part of their program. But hold on a sec – new research finds that this may actually be a counterproductive way to diet! People who sit down to eat after a fast are more likely to ignore protein, fats, and vegetables and head straight for yummy but super high-calorie carbs and starches first.

This may seem like common sense, but the study also revealed some telling details about food choices and the order in which we eat different kinds of foods. When given the opportunity to eat a salad and a plate of fries, for example, people who started with the starchy fries downed significantly more calories per meal than those who did the reverse. Interesting!

According to a New York Times article by Anahad O'Connor, the findings have implications for people who regularly miss meals, whether due to hectic schedules or for the deliberate purpose of losing weight.

Dr. Aner Tal and his colleagues at the Food and Brand Lab at Cornell knew from previous research that hunger influences food choices. After skipping a meal or two, people naturally tend to consume more calories than they otherwise would when finally given the opportunity to eat. Studies have also shown that high-calorie foods stimulate greater activity in reward centers of the brain when people eat them after missing breakfast.

But the researchers also wanted to know whether hunger, in addition to causing greater caloric intake, would also cause people to gravitate toward certain types of foods when given an array of choices. To find out, they divided 128 Cornell students in to two groups. One group was told to fast for 18 hours — starting at 6 p.m. — and then to show up the next day for a buffet-style lunch. The second bunch of students, serving as the control group, did not fast the night before.

Over the course of 12 weekday lunches, the researchers studied the students as they arrived at the lunch table. The subjects had their pick of starches, including dinner rolls and fries, as well as vegetables, beverages and proteins like chicken and cheese. To prevent the foods’ placement from influencing the results, the researchers rearranged the items at each meal. They also measured the amounts the subjects served themselves.

Those in the group that had fasted, it turned out, were more likely to begin their meals with starches, eating the bread or fries before anything else about a third of the time, compared to just over 10 percent of the time with the control group. Those who fasted were also less likely to eat vegetables first. Only a quarter of them did so, compared with about half of the people in the control group.

“Importantly,” the researchers wrote, “starting their meal with a particular food led all participants to consume 46.7 percent more calories of it” compared with other foods. They also found that people who chose not to eat the vegetables first consumed about 20 percent less of them. Those who went straight for the starches ultimately ate about 20 percent more calories overall than their peers.

“This shows that what you choose first is important when it comes to how much you ultimately eat,” Dr. Tal said.

So not only does fasting tend to make you feel lousy, but it’s also probably not helping you accomplish your dietary goals in a healthy way. Effective dieting is all about eating smart, not eating nothing! For regular dieters and people who frequently find themselves ravenous after missing meals, Dr. Tal said the lesson is to keep high-calorie foods out of reach, or at least make them less visible in the pantry or kitchen cabinets.