Then you get an e-mail from your best friend, beckoning you to happy hour, which turns into a late dinner at a restaurant where even the salads are fried.
And ... sigh ... you've fallen off the dieting wagon yet again.
Such is the life of the twentysomething. Not a teen, yet not quite a full-blown adult, twentysomethings often live on their own, are in school or working and making their own decisions about what to eat.
Unfortunately, when all the typical twentysomething has in the cooking arsenal is a George Foreman Grill and a microwave, it can be all too tempting to forget eating at home and hit the drive-through instead.
But there is good news for twentysomethings who want to make their dining habits a little more grown-up. Dietitians say it's simpler than ever to incorporate healthy fare into your life.
For Converse College student Dawn Cates, however, healthy eating still seems next to impossible. "Sometimes I only eat once a day," said Cates, 25, who lives in Spartanburg.
After a long day of classes and work, the last thing Cates wants to do is cook. Good thing: Cates doesn't know how to fix anything other than breakfast, which she doesn't eat because she's too busy.
"I would love to learn how to cook, but I just don't have time," she said.
While Cates occasionally buys frozen dinners, they're gone within a few days. Then it's just easier to get fast food on her way from school to work, and again on her way home.
The world, Cates said, just seems to be set up to make it easier to eat unhealthy foods.
Matt Whitehead also finds healthy eating a bit of a challenge.
"I think there's not a whole lot of advantage in cooking if you're single," said Whitehead, 24, a second-year law student at the University of South Carolina.
Between the amount of time it takes to cook, and the fact that he ends up throwing away a lot of leftovers, "It's really not worth it."
Whitehead's days begin at 6 a.m., but he typically doesn't eat his first meal until between 11 a.m. and 1 p.m. That's usually fast food, a burger or a sandwich.
During the day, Whitehead will snack on crackers and drink "a lot" of coffee and soda. When he gets home around 8 p.m., he'll sometimes fix a frozen pizza or a chicken casserole, but often it's just easier to meet up with his friends and go out to dinner or to happy hour. His friends favor restaurants where they can get homestyle meals.
Law school typically means a lot of late nights, which means late-night snacking. Whitehead keeps his fridge stocked with lunchmeat and will often snack on sandwiches.
Whitehead's sandwich snacks are a perfect example of what dietitians emphasize -- eating right doesn't have to be time-consuming.
"You don't have to spend three hours cooking to have a healthy diet," said Stephanie Tranen, a registered dietitian and director of the dietetic internship program at the Medical University of South Carolina.
Here's some expert advice on how to turn those bad eating habits into habits even your mom can be proud of:
Eating whatever you want gets you into bad habits that can be hard to break, said Colleen Wracker, a registered dietitian with outpatient cardiac rehabilitation at Palmetto Health Richland.
You're also likely shorting yourself on proper nutrition, Wracker said. Even if the effects don't show up right away, you're still setting yourself up for potential problems down the road, such as diabetes and heart disease.
"We think for the moment; we live for the moment," Wracker said. "We think we're invincible."
When you're going out to eat (or drink), the key is moderation. Just because your friends are scarfing down a plate of extreme nachos or downing a bucket of beer doesn't mean you have to, though that can be easier said than done.
Tranen recommends ordering what you want, but immediately dividing it in half, or thirds, and setting the excess aside. And if you can't control yourself, tell the waiter to only bring you part of your meal.
Or you could dump a bunch of salt, pepper or ketchup on top of the extra, rendering it inedible.
You can curb your appetite by drinking a glass of water before your food arrives. If you're having a cocktail, have your server bring it with the meal. Otherwise you're likely to end up downing at least one drink before your food comes. Alcohol has 7 calories per gram, which is about 105 calories per standard drink. And, like potato chips, who can drink just one?
If going out drinking makes you crave a burger and fries, down a glass of water before you start munching. Sometimes alcohol can trick you into thinking you're starving when you're simply dehydrated, Wracker said.
If you still want a snack, think of alternative foods that will satisfy your craving. If you like something sweet, keep some low-fat yogurt in the freezer. Salty? Try pretzels. Crunchy? Have some baby carrots. Breakfast foods? You can buy a carton of egg whites and whip up a healthier form of scrambled eggs.
And remember -- you don't always have to center your social life around food and drink. Get together with friends to work out or train for a race, suggests Tranen.
Above all, don't let one bad day, or night, or week derail your goals of a healthier lifestyle.
"It's a lifelong struggle for everyone," Tranen said.
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