Intermittent Fasting Can Make You Gain Weight, Says New Study
You have a special occasion coming up, so you decide to try one of the trendy new intermittent fasting approaches. Eat normally for five days, cut your calories to a mere 500 to 600 per day, and you'll lose weight, say advocates of this approach. But there's one problem,according to a new study reported on July 13: You might fit into those skinny jeans for the big occasion, but that diet plan can actually make you fatter when you abandon the diet.
The problem centers on the self-denial involved in these highly restricted diets. Dr. Eric Stice, who headed up the study at the Oregon Research Institute, examined why so many people gain weight after the diet ends. Dr. Stice pinpointed the restricted calorie diets as the culprit. "The story is a familiar one: most people are able to lose weight while dieting but once the diet is over, the weight comes back. Many of us can personally attest that caloric deprivation weight loss diets typically do not produce lasting weight loss."
Restricted Food Intake Equals Weight Gain in the Long-Run
When you restrict food so much, as typifies an intermittent fasting approach, it makes it more difficult to maintain your weight loss, says Dr. Stice. His research revealed "that restricting food intake increases the reward value of food, particularly high-calorie, appetizing food such as chocolate milkshakes and that the more successful people are at caloric-restriction dieting, the greater difficulty they will face in maintaining the restriction." In addition, when you fast for a full 24 hours or limit yourself to just 500 calories, you are increasing "the reward value of food, which may lead to poor food choices when the individual eventually does eat.”
The popular intermittent fasting diets generally allow you to eat what you want five days a week after drastically slashing your calories two days a week. Dr. Stice's research suggests that because you feel so deprived after those two restricted calorie days, you may actually eat so much that you negate the benefits of those two "fasting" days.
“Results imply that dieting characterized by meal skipping and fasting would be less successful than weight loss efforts characterized by intake of low energy, healthy foods,” he said.
To determine what is effective for weight loss, Dr. Stice compared how study participants reacted when shown photos of tasty foods, icky foods and glasses of water. He also measured their responses to eating and anticipation of eating fattening foods such as a chocolate milkshake versus calorie-free.
"These results are unique in that these data are the first to suggest that elective caloric restriction increases the degree to which brain regions, implicated in reward valuation and attention, are activated by exposure to palatable foods," said Dr. Stice. "The implications of this imaging study are crystal clear; if people want to lose excess weight, it would be more effective to consume healthy, low-fat/low-sugar foods during regular meals, rather than go for long periods of time without any caloric intake.”