Skip to main content

What you thought you knew about obesity is wrong

By Aaron Carroll, Special to CNN
February 5, 2013 -- Updated 1620 GMT (0020 HKT)
 Aaron Carroll says some studies have upended the received wisdom on obesity: There is no one-size-fits-all solution
Aaron Carroll says some studies have upended the received wisdom on obesity: There is no one-size-fits-all solution
STORY HIGHLIGHTS
  • Aaron Carroll: I thought I knew all about obesity; a new study challenges that
  • He says obesity a big problem, but weight loss not as simple as fruits, veggies and no snacks
  • Studies do show that overall, vigorous exercise and watching calories help
  • Carroll: Best tool against obesity is not to get there in first place

Editor's note: Dr. Aaron E. Carroll is an associate professor of pediatrics at the Indiana University School of Medicine and the director of the university's Center for Health Policy and Professionalism Research. He blogs about health policy at The Incidental Economist and tweets at @aaronecarroll.

(CNN) -- I've written quite a bit about medical myths, so I'm always a bit skeptical about medical "knowledge." But one thing I, and I'm sure many of you, think we understand is obesity. After all, weight issues crop up in media constantly. Just last night, Gov. Chris Christie was joking about donuts and his weight on The Late Show with David Letterman, and the First Lady's weight is once again a subject of discussion in the Washington Post--even though by any objective standard she's in great shape.

We know how people gain weight, and we think we know how to lose it.

Except a study in this week's New England Journal of Medicine shows us that's just not right. Pretty much everything we "know" about obesity and weight loss is wrong.

Let's start with some things that are true.

More than a third of Americans are obese. Many more are overweight. The Centers for Disease Control and Prevention estimates that obesity-related medical costs were almost $150 billion in 2008, and the cost in health related expensed for an average person who was obese was more than $1,400. This doesn't count the physical, mental or quality-of-life toll that obesity can levy on a person.

Few of us dispute that we need to do something about this problem. There are plenty of experts (present company included) who will tell you what needs to be done. The sad truth, though, is that lots of that advice (even mine) turns out to be mistaken.

Aaron Carroll
Aaron Carroll

I know I've told people that making small, sustained lifestyle changes is the best way to lose weight over time. But it turns out that making such changes, say by deciding to walk a mile every day for five years, results in far less weight loss than you'd expect.

Coca-Cola weighs in on obesity fight

I've lectured people about the importance of physical education in schools, and I've seen countless reports declaring that the decrease in PE nationwide is one of the reasons that more children are obese or overweight today. It turns out that studies don't show that's the case.

My family loves watching "The Biggest Loser." But I've found myself telling my kids again and again that what's shown on TV isn't the best way to lose weight. I tell them that slow and steady works better in the long-run than rapid weight loss. I also tell them that setting unrealistic weight goals can actually sabotage your efforts.

So imagine my shock to discover that what evidence exists in this new study hints towards ambitious goals being a good thing, and that quicker weight loss isn't less likely to be kept off in the long-term.

Bacteria in gut may cause morbid obesity
Coke's new ad campaign targets obesity
FDA expected to approve new diet drug
NYC's controversial move to curb obesity

People will say eating breakfast is a good idea when you're trying to lose weight, because it will keep you from binging later. But studies show that there's no protective effect from eating breakfast at all. People will say that eating more fruits and vegetables is a great way to lose weight. But studies show that, on their own, eating more of them without making other behavioral changes doesn't result in any weight loss. There's no magic to fruits and vegetables.

Eatocracy: Chefs with Issues: Farm-to-table should still be on the table

People will say that snacking in between meals can lead to weight gain. But studies don't show that to be the case either. In general, people compensate for snacking throughout the rest of the day. In other words, it's not necessarily bad to snack outside of usual meal times.

It's all enough to cause one to despair. But just because so much of what we believe is wrong doesn't mean we still can't do something about the issue.

Studies do show that you can absolutely overcome genetic and familial factors to lose weight.

They show that significant physical activity can help with weight loss, and that it has the added bonus of making you healthier in general. Reducing your caloric intake works overall, especially if it's done in a way to change your overall eating habits. Getting the whole family involved is important. And finally, for some, bariatric surgery can result in life-changing outcomes.

Over the past five years, my wife and I have lost quite a bit of weight. I'm down somewhere between 15% to 20% of my high of more than 200 pounds. My wife lost even more, although I'm not going to give you any numbers (I like being married).

Now that I look back, if I'm going to be honest about it, I did it in bursts over a few months here and there, each time gaining back less than I had lost.

7 weight loss myths (sort of) debunked

Each time, I had ambitious goals of 15 pounds or more in two to three months, and each time I really restricted my caloric intake. But I've kept the weight off by radically changing my overall eating habits.

My breakfast consists of just coffee, I eat very light lunches, such as salads, and dinner is usually a healthy home-cooked meal with the family. My wife cooks way more than she used to and is obsessed with finding ways to make meals healthier. I avoid fried foods almost entirely, and I can't remember the last time I ate in a fast food restaurant. I also get to the gym two to three times each week.

I don't tell you this because I think this is what you should do, or because I think it's the key to getting thinner. I tell you this because more and more, I think that the journey to sustained weight loss is a very personal and individual path. Perhaps our problem is we're trying to find a one-size-fits-all solution. I'm not sure that exists.

Lastly, what was left out of this new scientific paper was prevention. The single best way to fight obesity is to avoid it in the first place. That has to start when kids are young, and it's a lifelong journey. But one thing I doubt will ever be proved false is that it's much easier not to gain the weight in the first place than to take it off later.

Follow us on Twitter @CNNOpinion.

Join us on Facebook/CNNOpinion.

The opinions expressed in this commentary are solely those of Aaron Carroll.

ADVERTISEMENT
Part of complete coverage on
April 17, 2014 -- Updated 1453 GMT (2253 HKT)
Michael Bloomberg and Shannon Watts say Americans are ready for sensible gun laws, but politicians are cowed by the NRA. Everytown for Gun Safety will prove the NRA is not that powerful.
April 17, 2014 -- Updated 1328 GMT (2128 HKT)
Ruben Navarrette says Steve Israel is right: Some Republicans encourage anti-Latino prejudice. But that kind of bias is not limited to the GOP.
April 16, 2014 -- Updated 2323 GMT (0723 HKT)
Peggy Drexler counts the ways Phyllis Schlafly's argument that lower pay for women helps them nab a husband is ridiculous.
April 16, 2014 -- Updated 1642 GMT (0042 HKT)
Rick McGahey says Rep. Paul Ryan is signaling his presidential ambitions by appealing to hard core Republican values
April 16, 2014 -- Updated 1539 GMT (2339 HKT)
Paul Saffo says current Google Glasses are doomed to become eBay collectibles, but they are only the leading edge of a surge in wearable tech that will change our lives
April 15, 2014 -- Updated 1849 GMT (0249 HKT)
Kathleen Blee says the KKK and white power or neo-Nazi groups give haters the purpose and urgency to use violence.
April 16, 2014 -- Updated 1156 GMT (1956 HKT)
Sen. Sheldon Whitehouse and Rep. Henry Waxman say read deep, and you'll see the federal Keystone pipeline report spells out the pipeline is bad news
April 16, 2014 -- Updated 1153 GMT (1953 HKT)
Frida Ghitis says President Obama needs to stop making empty threats against Russia and consider other options
April 15, 2014 -- Updated 2129 GMT (0529 HKT)
Peter Bergen and David Sterman say the Kansas Jewish Center killings are part of a string of lethal violence in the U.S. that outstrips al Qaeda-influenced attacks. Why don't we pay more attention?
April 15, 2014 -- Updated 1641 GMT (0041 HKT)
Danny Cevallos says families of the passengers on Malaysian Airlines Flight 370 need legal counsel
April 14, 2014 -- Updated 1523 GMT (2323 HKT)
David Frum says Russia is on a rampage of mischief while Western leaders and Western alliances charged with keeping the peace hem and haw
April 14, 2014 -- Updated 1156 GMT (1956 HKT)
Most adults make the mistakes of hitting the snooze button and of checking emails first thing in the morning, writes Mel Robbins
April 14, 2014 -- Updated 1754 GMT (0154 HKT)
David Wheeler says as middle-class careers continue to disappear, we need a monthly cash payment to everyone
April 14, 2014 -- Updated 1155 GMT (1955 HKT)
Democrats need to show more political spine when it comes to the issue of taxes.
April 14, 2014 -- Updated 1555 GMT (2355 HKT)
Donna Brazile recalls the 50th Anniversary of the Civil Rights Act as four presidents honored the heroes of the movement and Lyndon Johnson, who signed the law
April 14, 2014 -- Updated 1317 GMT (2117 HKT)
Elmer Smith remembers Chuck Stone, the legendary journalist from Philadelphia who was known as a thorn in the side of police and an advocate for the little guy
April 13, 2014 -- Updated 1856 GMT (0256 HKT)
Al Franken says Comcast, the nation's largest cable provider, wants to acquire Time Warner Cable, the nation's second-largest cable provider. Should we be concerned?
April 11, 2014 -- Updated 1522 GMT (2322 HKT)
Philip Cook and Kristin Goss says the Pennsylvania stabbing attack, which caused grave injury -- but not death, carries a lesson on guns for policymakers
April 11, 2014 -- Updated 1906 GMT (0306 HKT)
Wikipedia lists 105 football movies, but all too many of them are forgettable, writes Mike Downey
April 11, 2014 -- Updated 1432 GMT (2232 HKT)
John Sutter and hundreds of iReporters set out to run marathons after the bombings -- and learned a lot about the culture of running
April 11, 2014 -- Updated 1649 GMT (0049 HKT)
Timothy Stanley says it was cowardly to withdraw the offer of an honorary degree to Ayaan Hirsi Ali. The university should have done its homework on her narrow views and not made the offer
April 11, 2014 -- Updated 1416 GMT (2216 HKT)
Al Awlaki
Almost three years after his death in a 2011 CIA drone strike in Yemen, Anwar al-Awlaki continues to inspire violent jihadist extremists in the U.S, writes Peter Bergen
April 12, 2014 -- Updated 0121 GMT (0921 HKT)
David Bianculli says Colbert is a smart, funny interviewer, but ditching his blowhard persona to take over the mainstream late-night role may cost him fans
April 10, 2014 -- Updated 1731 GMT (0131 HKT)
Rep. Paul Ryan says the Republican budget places its trust in the people, not in Washington
April 10, 2014 -- Updated 2128 GMT (0528 HKT)
Aaron David Miller says Obama isn't to blame for Kerry's lack of progress in resolving Mideast talks
April 14, 2014 -- Updated 1522 GMT (2322 HKT)
David Weinberger says beyond focusing on the horrors of the attack a year ago, it's worth remembering the lessons it taught about strength, the dangers of idle speculation and Boston's solidarity
April 10, 2014 -- Updated 1632 GMT (0032 HKT)
Katherine Newman says the motive for the school stabbing attack in Pennsylvania is not yet known, but research on such rampages turns up similarities in suspects and circumstances
April 9, 2014 -- Updated 1839 GMT (0239 HKT)
Wendy Townsend says the Rattlesnake Roundup -- where thousands of pounds of snakes are killed and tormented -- is barbaric
ADVERTISEMENT