If the weight you report on your driver’s license is a few pounds shy of what appears when you weigh in at the doctor’s office, you’re not alone. Americans weigh more than they think, and this is especially true with older Americans, a new study suggests.

The study, published in the journal Preventive Medicine, shows that the rate of obesity rose between 2008 and 2009, yet people surveyed in the study said, on average, that they lost weight during the same time period.

“We all know on some level that people can be dishonest about their weight,” said Dr. Ali Mokdad, a professor of global health at the Institute for Health Metrics and Evaluation, which conducted the study. “But now we know that they can be misreporting annual changes in their weight.”

According to the study, the average American was off by one pound; people older than 50 were off by two pounds and diabetics misreported by four.

The study analyzed the Behavioral Risk Factor Surveillance System (BRFSS) and an annual phone survey conducted by the CDC in 2008 and 2009. It included survey responses of more than 775,000 people regarding their current weight and how much they weighed a year earlier.

"If self-reported changes in weight between 2008 and 2009 are to be believed, the obesity prevalence among men and women in the United States would have declined by 2 percent and 0.9 percent respectively," according to the study. Yet the prevalence of obesity increased from 26 percent to 26.5 percent between those two years.

It may seem like “duh” news in a country known for its overwhelming obesity problem (more than a third of American adults are obese, according to the CDC) and its looks-driven culture. Who hasn’t fudged a few pounds? But Dr. Catherine Wetmore, the paper’s lead author, said the study hints at a “serious problem.”

“There are plenty of programs designed to help people lose weight,” Wetmore said, “and I think that one of the barriers in engaging in those healthy behaviors is believing you don't need to implement [them] in your life. If people aren’t acknowledging [their true weight], they’re not going to be motivated to lose weight or maintain their healthy weight.”

Yet Adam Drewnoski, director of the Center for Public Health Nutrition at the University of Washington, said he didn't think the study’s findings were that dramatic.

“Some people may also value fitness or performance as opposed to mere pounds and do not care what they weigh as long as they are happy," Drewnoski said. "So yes, better awareness of body weight would make public health interventions easier and more effective ... but being a pound off is not the worst thing in the world.”

This isn't the first study to show a conflict between self-reported and actual weight. A 2011 study published in the Archives of Internal Medicine found that people who are overweight or obese may need to hear that from their doctor before they actually believe it. More than 7,700 participants had two body mass indexes tabulated for the study: one based on the height and weight they reported and the other on their actual measurements. When a doctor hadn't consulted them on their weight, 66.4 percent of obese participants said they didn't think they were overweight. But a whopping 94 percent of those who had been told they were overweight by their doctor acknowledged the fact.

Amanda Chan contributed to this piece.

Earlier on Huff/Post50:

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  • Know What You Should Weigh

    Sounds obvious, doesn't it? Surprisingly, many people who admit they could "maybe stand to lose a few pounds" actually have more serious weight problems than they are admitting to. Try this <a href="http://www.nhlbisupport.com/bmi/" target="_hplink">body mass index calculator </a>to see where you fall, and check with your doctor about what your ideal weight should be to avoid health problems.

  • Skip The Fad Diets And Stick To The Basics

    It's human nature to want a quick, painless fix to all our problems, which is the appeal of fad diets. These diets take many forms including focusing on one particular food item, such as grapefruit. The problem is that these diets often lack the major nutrients and protective phytochemicals that we need, such as antioxidants, according to <a href="http://women.webmd.com/fad-diets" target="_hplink"> WebMd.com</a>. Sorry, there's no magic pill for being overweight. <em>Photo courtesy of <a href="http://www.flickr.com/photos/calliope/" target="_hplink">Muffet</a></em>

  • Rome, And Weight Loss, Weren't Built In A Day

    Weight loss needs to be gradual if it's going to stick. You've heard (and probably ignored) the adage that the most successful diet is one that involves a lifestyle change. In plain English, they mean skip the potato chips and convince yourself that carrot sticks are just as satisfying. Check with your doctor for what the best diet is for you. Set realistic goals so that you wean yourself off the bad habits and maintain your weight loss. After all, what good is losing it if you just regain it when you slip into old eating patterns?

  • Learn Portion Control

    Carbs may feel like the enemy, but instead of demonizing them, learn to eat a correct portion size -- which unfortunately is not an entire pizza or a giant bowl of pasta with meat sauce. Many people don't actually know what a correct portion size looks like. Weight Watchers defines a portion of meat -- like grilled chicken -- as the size of a <a href="http://www.weightwatchers.com/about/prs/wwi_template.aspx?GCMSID=1002991" target="_hplink">deck of cards</a>. Uh-huh. Did you just pack double that amount on your salad for lunch and think you were being virtuous?

  • Measure, Don't Eyeball

    Once you know what a portion size is, don't trust your judgment. Measure it. One of the most shocking things to learn is what a half cup of rice actually looks like. <br> <em>Photo courtesy of <a href="http://www.flickr.com/photos/b_2/" target="_hplink">B*2</a></em>

  • Write Down What You Eat

    Bites add up -- or "Just let me have one bite," said the dieter to the Devil. While there are some who can stop after one bite, there are many who can't. And if you add up your bites all day long, you just may be surprised how many calories you've added to your diet. <br> <em>Photo courtesy of <a href="http://www.flickr.com/photos/marcoarment/" target="_hplink">Marco Arment</a></em>

  • Get Out There And Move

    Can this be said often enough? Walk the dog around the block instead of just opening the back door. Grab a friend and walk in the mall in inclement weather. Nobody is expecting you to hit five pilates classes a week, but try to move for at least <a href="http://www.heart.org/HEARTORG/GettingHealthy/PhysicalActivity/StartWalking/American-Heart-Association-Guidelines_UCM_307976_Article.jsp#.T00dlHLOzDU" target="_hplink">30 minutes a day, five days a week</a>. <br> <em>Photo courtesy of <a href="http://www.flickr.com/photos/revstan/" target="_hplink">Rev Stan</a></em>

  • Find A Gym That Works For You Or Get Your Own Equipment

    Is there anything more depressing than huffing and puffing on a treadmill while surrounded by hard-bodied 20-somethings running much faster but who have barely broken into a sweat? My answer was just to invest in a used treadmill and put it in the garage. I hop on it at my convenience and in privacy.

  • Figure Out What Works For You As Incentives

    I know a woman who starts out her diet buying a new pair of jeans in the size she aims to wear. I know someone else who tapes a college photo of herself on the refrigerator door. Me? I put my kids' pictures up there to remind me why I don't really want to eat the ice cream.

  • Dieting Isn't A Competition

    Some like the support that attending diet program meetings provides. Others say it turns into a competition. When it comes to dieting, you fool no one but yourself and that's the only person you answer to. The brass ring here doesn't go to who drops 30 pounds soonest. You are doing this for yourself, your health and your well-being. Don't put yourself in a situation where you feel so bad that others seem to be having an easier time of things that you get discouraged and quit.

  • Dieting Plateaus Are Tough But Can't Be The End Of The Road

    Many people hit <a href="http://www.webmd.com/diet/features/10-ways-to-move-beyond-a-weight-loss-plateau" target="_hplink">diet plateaus</a>. Things start to slow and level off, and once in a while, your scale gets stuck at a point. Nothing you do seems to help, and frustration sets in. Relax and know that just staying the course will eventually rev up your metabolic engine again. It's the hardest part of dieting. One suggestion: Try <a href="http://www.cnn.com/2010/HEALTH/08/23/drink.water.lose.weight/index.html" target="_hplink">drinking more water</a> -- it may help you lose the pounds. <br> <em>Photo courtesy of <a href="http://www.flickr.com/photos/22280677@N07/" target="_hplink">Svadilfari</a></em>

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