Perhaps you ate more than you intended this past weekend – a few glasses of wine, a hefty serving of dessert and salty popcorn at the movies. And Monday morning, not surprisingly, the bathroom scale registered an extra two pounds from Friday morning.
Don’t panic. That small weight increase isn’t body fat. It’s pretty much impossible to gain even one pound of fat from a day of overeating.
So, that’s good news.
The bad news, though, is that if you don’t get your diet back on track now, you could easily pack on a few pounds of fat before January 1st. (Lingering Halloween candy that should be long gone and the upcoming string of holiday parties make this entirely possible.)
How you gain body fat
It takes days of overeating for accumulated body fat to show up as measurable weight gain.
Once food is digested, its building blocks (e.g., glucose, amino acids, fatty acids) are absorbed into the bloodstream. Your cells use what they need for fuel and store the rest in fat cells for later use, a process that begins six to eight hours after eating a meal.
So yes, eating more calories than your body needs in one sitting (or over the course of a day) will result in some of them being tucked away as fat. But not enough to move the needle on the scale. (Unless you really, really gorge.)
Consider the math. Let’s say you typically consume 2,000 calories a day and that your weight is pretty stable. In other words, you’re eating enough calories to prevent gaining or losing weight.
Theoretically, one pound of body fat contains roughly 3,500 calories. That means that in order to gain a pound of fat, you’d have to eat 3,500 calories above and beyond what you would normally eat in a day.
To pile on an extra 3,500 calories – and not burn them off – would be a feat. Even a fully-loaded steak dinner with all the fixings, a decadent dessert, and two glasses of wine clocks in around 2,000 calories. You’d have to eat all of that plus more on top of what you usually eat.
Of course, how people’s bodies respond to excess calories – and how quickly those calories add extra weight – varies. Scientists are learning that the biology of weight gain is individualized; a person’s unique physiological and hormonal responses to food play a role.
Weight gain culprits
The extra few pounds you register on Monday(s) reflect water weight. When you eat a large quantity of food you also take in extra sodium which causes your body to retain water.
Eating extra carbohydrates contributes, too. Excess carbohydrates from large portions of starchy foods (e.g., bread, pizza, pasta) and sugary desserts also cause water retention.
Some of that weight might also be the meal itself. It takes about 24 hours before your body begins to eliminate undigested food residue (e.g., waste).
So, you’ve gained a little water weight, not a surplus of fat cells. If you resume your usual healthy diet and drink plenty of water, you’ll lose that extra fluid in a couple of days.
Don’t delay, though. Soon you’ll have to strategize your way around December’s calorie minefield.
All research on this web site is the property of Leslie Beck Nutrition Consulting Inc. and is protected by copyright. Keep in mind that research on these matters continues daily and is subject to change. The information presented is not intended as a substitute for medical treatment. It is intended to provide ongoing support of your healthy lifestyle practices.