What Eating 1,000 Extra Calories a Day Does to Your Body
Short periods of overindulgence may not affect your body as much as you fear, new research out of the American Journal of Physiology-Endocrinology and Metabolism suggests.
Eating 1,000 extra calories a day for five days did not lead to any significant changes in weight, fat mass, or fasting blood sugar levels.
But chronic overeating-eating 1,000 extra calories a day over the course of a month-was linked to a fat-mass increase of about 3 pounds, as well as increases in blood sugar.
You stay on track in terms of your nutrition most of the time, but when a special occasion or holiday pops up, you may turn off your mental calorie tracker for a bit. So how much will that feast set you back?
According to a new study published in the American Journal of Physiology-Endocrinology and Metabolism, it might not be as bad as you think: A short period of overindulgence may register as more of a blip to your body than a major stumble in terms of weight or fat storage.
To come to that conclusion, researchers from Deakin University in Australia put the feast to the test. They recruited eight healthy young men, with an average age of 22, and put them on high-calorie diets for two different timeframes: five days, which is representative of holidays, and 28 days to emulate long-term chronic overeating.
During each time period, they ate approximately 1,000 more calories per day-much of the excess made up of junk like potato chips, chocolate, and calorie-rich drinks-than they normally consumed, or about 46 percent more than their usual total. Their weight, fat mass, blood sugar, and insulin levels were measured before the research period began, and again after each diet timeframe.
[Build a killer midsection in the kitchen for powerful, effortless miles on the road with Eat for Abs!]
At the end of the five-day period of caloric glee, the participants’ visceral fat-the harmful stuff that accumulates around the abdominal organs-increased by 14 percent. But in other measures of body composition, the five-day binge didn’t have much effect. In fact, there was no significant difference in overall weight or fat mass.
By the end of the 28 days, though, it was a different story: At the end of a month of overfeeding, their fat mass increased by nearly 3 pounds, bringing their average weight gain to about 3.5 pounds.
Researchers also noted that the body copes with short periods of increased calorie consumption by shifting the metabolism in a way that favors use of carbohydrates. This actually runs counter to what the researchers first hypothesized, which was that short-term overeating would first impair the liver, and then muscle later. But that switchover to using carbs prevents that, making it a benefit in the short term, according to lead researcher Glenn Wadley, Ph.D., in the School of Exercise and Nutrition Sciences at Deakin University.
That early adaptation may help even out how your body deals with blood sugar, he said-which may explain why the participants had no changes in their fasting blood sugar after five days of eating junk. But that carb utilization doesn’t seem to work as a long-term strategy: Fasting blood sugar was slightly higher after the 28-day overeating period.
The study, obviously, has its limitations. Most notably, the sample size is very small, and done only on young men. Also, the conditions leading up to the “feast time” were highly controlled-subjects had refrained from exercise and alcohol for 48 hours beforehand, and had eaten a specific diet the day before containing 55 percent carbs, 30 percent fat, and 15 percent protein-macros chosen based on the typical composition of the Australian diet.
The overeating time period also used the same macro breakdown. Wadley noted that it’s likely the signs of impairment to the metabolic system would be worse, or at least faster, if you were to overindulge with a more high-fat diet.
Despite those caveats, the results do give some insight into how bodies, in general, may be able to adapt to a few days of feasting without significant impairment, said Wadley.
From an evolutionary perspective, this mechanism is likely in place to prepare us for the next famine period, he said, meaning the body is pretty smart at creating changes to energy consumption based on anticipated short-term needs.
But when days of feasting stretch into weeks and months of overindulgence, that’s when problems set in, like increased risk of insulin resistance, a condition that occurs when your body can’t readily absorb blood sugar, raising your levels and upping your chances of prediabetes or diabetes.
He added that more research needs to be done, particularly on people of different age groups as well as women. But for now, this seems to indicate that celebrate without feeling like a health saboteur.
“We aren’t advocating that regular binge eating is okay,” said Wadley. “But from a health perspective, short-term overeating, like during festivals and holidays, can be withstood by the body without long-term effects.”
('You Might Also Like',)