Childhood obesity is epidemic. We see evidence of it every day – at mall food courts, in video arcades, at school bus stops. But just how bad is it and how much is it costing us?

‘Child Obesity: The Way Forward’ is the theme of the March 2010 issue of Health Affairs, a leading health policy journal. In a special briefing held in Washington, D.C. to highlight the journal issue, authors summarized their work, policy briefs were circulated, and passionate individuals shared questions and experiences. Here are some key numbers from the meeting and journal papers to quantify the magnitude and implications of what we see every day. (Full references are below.)

How bad is the childhood obesity epidemic?

• Nearly one in three U.S. children and adolescents aged 2 through 19 years are overweight or obese (more than 23 million youth). [Odgen 2010]
• About one in six children (16.4%) ages 10 to 17 are obese. [Bethell, Singh]
• Nearly one in three very young children who enroll in Head Start programs are overweight or obese. [Tarullo]
• Over the past 40 years the rates of overweight and obesity have more than quadrupled among children ages 6 to 11, and have more than tripled for adolescents ages 12 to 19. [Data spanning from 1963 to 2004; Ogden 2002, 2006]

Disparities, and disparities within disparities

• Across states, there is a wide range in the prevalence of overweight and obesity among children ages 10-17, ranging from 23.1% in Utah and Minnesota to 44.4% in Mississippi. [Bethell]
• Between 2003 and 2007, the disparity in the prevalence of overweight and obesity in U.S. children ages 10-17 grew wider between publicly and privately insured children, lower-and higher-income children, and Hispanic and non-Hispanic children. [Bethell]
• Nationally, in 2007, 44.8% of children in poverty were overweight or obese, compared to 22.2% of children living in households with incomes above 400% of poverty. The disparities based on poverty vary two- to threefold across states. [Bethell]
• Illustrative of the substantial disparities that exist within states as well as among states, Minnesota had the highest disparity ratio (2.61) between children with private vs. public health insurance, despite having one of the lowest overall overweight/obesity rates nationally.  [Bethell]

Food and drink

• Sugar-sweetened beverages and 100% fruit juice comprise 10-15% of the total calorie consumption of children and adolescents (ages 2-19).  [Frieden, Wang]
• Americans’ average daily calorie intake in 2007 was 400 calories higher than in 1985, and 600 calories higher than in 1970. [Wallinga]
• The inflation-adjusted price of carbonated soft drinks decreased ~24% from 1985 to 2000, while the prices of fresh fruit and vegetables rose 39% (based on USDA data). [Wallinga]
• Less than one in ten Americans meet the levels of fruit and vegetable consumption recommended in the 2005 Dietary Guidelines for Americans. [Wallinga]

Physical activity

• Only 42% of children ages 6-11 years, and only 8% of adolescents’ ages 12-19 years, obtain the recommended 60 min/day of physical activity.  [Troiano]
• A quarter of high school students do not meet recommended levels of physical activity (60 minutes of moderate-to-vigorous activity per day) on any day. [Frieden, Eaton]
• Less than 4% of adults engage in enough physical activity to improve health, although approximately 40% of adults claim they do. [Frieden, Troiano]
• The odds are 1.21 times greater for a child to be overweight or obese if they do not participate in sports and other activities outside of school. [Bethell]
• The odds are 1.21 times greater for a child to be overweight or obese if they do not have local access to a park or recreation center. [Bethell]

Lifestyle & environment

• Children who have a TV in their bedroom or watch more than 2 hours of TV on average per day are more than 1.5 times likely to be overweight or obese. (This relationship holds when socioeconomic and other factors are adjusted for). [Bethell]
• For U.S. children ages 10-17, 35.0% have no access to recreation or community centers; 26.7% have no neighborhood access to sidewalks or walking paths; and 19.2% have no access to parks or playgrounds (as reported by their parents). [Singh]
• Children living in neighborhoods with the most unfavorable social conditions are 50% more likely to be physically inactive; 52% more likely to watch TV more than 2 hours a day; and 65% more likely to engage in recreational computer use of more than 2 hrs/day, as compared to children living in most favorable social conditions (based on 2007 data).  [Singh]
• Children living in unsafe neighborhoods have 61% higher odds of being obese and 43% higher odds of being overweight than children living in safe neighborhoods (after adjusting for age and sex).  [Singh]
• Children living in neighborhoods with no access to sidewalks or walking paths, parks or playgrounds, and recreation or community centers, have 32%, 26% and 20% higher adjusted odds of obesity than children in neighborhoods with access to these amenities, respectively.  [Singh]

Health

• Approximately 70% of obese youth have at least one additional risk factor for cardiovascular disease, such as high blood pressure or high cholesterol. Nearly 40% have at least two additional risk factors.  [Frieden]
• Children who are obese after age 6 have greater than a 50% chance of being obese as adults, even if their parents are not obese. [Frieden]

School achievement

• The odds are 1.32 times greater for an overweight or obese child to repeat a grade in school. [Bethell]
• The odds are 1.59 times greater for an overweight or obese child to miss more than 2 weeks of school during the school year. (These data do not include children who have special health care needs.)  [Bethell]

How much does obesity cost?

• Almost 10% of all medical costs in 2008 were attributable to obesity. [Finkelstein]
• The estimated cost of treating obesity-related illness was $147 billion/year in 2008. [Finkelstein]
• The direct costs of childhood obesity include annual prescription drug, emergency room, and outpatient costs of $14.1 billion, as well as inpatient costs of $237.6 million. [Cawley]
• Obesity-related job absenteeism costs $4.3 billion annually. [Cawley]
• The decrease in productivity in obese individuals while at work (presenteeism) totals $506 per obese worker per year. [Cawley]
• Obesity-related illnesses cost Medicare $19.7 billion and Medicaid $8 billion in 2008. [Cawley]
• Private health insurance plans paid $49 billion to treat obesity-related illness in 2008. [Cawley]
• According to mathematical modeling, U.S. children who were age twelve in 2005 will incur an estimated $2.77 billion in attributable medical expenditures over their lifetime. The twelve-year-olds who were overweight and obese and become obese adults will incur an estimated additional $3.47 billion in medical expenditures. Further mathematical modeling indicates a one-percentage point reduction in obesity (from 16.3% to 15.3%) in children who were age 12 in 2005 would save $260.4 million in total medical expenditures. [Trasande]

What numbers do you find the most frightening?
What numbers are you going to change?

Definition of child overweight and obesity
Child overweight and obesity are based on body mass index, or BMI, which is based on height and weight measurements. Overweight is defined as the 85th through 94th percentiles of age- and sex- specific BMI; obese is defined as the 95th or greater percentile of age- and sex- specific BMI.  The CDC has information on BMI for children and teens, including a Child and Teen BMI Calculator.

References

• Bethell, C., et al. National, state, and local disparities in childhood obesity. Health Affairs, 29(3): 347-356, 2010. doi: 10.1377/hlthaff.2009.0762
• Cawley, J. The economics of childhood obesity. Health Affairs, 29(3): 364-371, 2010. doi: 10.1377/hlthaff.2009.0721
• Eaton, D. K., et al. Youth risk behavior surveillance — United States, 2007. MMWR Surveillance Summaries 57(4): 1-131, 2008.
• Finkelstein, E. A., et al. Annual medical spending attributable to obesity: Payer-and service-specific estimates. Health Affairs, 28(5): 357-363, 2009.  doi: 10.1377/hlthaff.28.5.w822
• Frieden, T., et al. Reducing childhood obesity through policy change: acting now to prevent obesity. Health Affairs, 29(3): 357-363, 2010. doi: 10.1377/hlthaff.2010.0039
• Odgen, C. L., et al. Prevalence of high body mass index in US children and adolescents, 2007-2008. JAMA 303(3):242-249, 2010. doi:10.1001/jama.2009.2012
• Ogden C. L., et al. Prevalence of overweight and obesity in the United States, 1999-2004. JAMA 295(13):1549-55, 2006.
• Ogden C. L., et al. Prevalence and trends in overweight among US children and adolescents, 1999-2000. JAMA 288(14):1728-32, 2002.
• Singh, G. K., et al. Neighborhood socioeconomic conditions, built environments, and childhood obesity. Health Affairs, 29(3): 503-512, 2010.  doi: 10.1377/hlthaff.2009.0730
• Tarullo, L., et al. Beginning Head Start: Children, families and programs in fall 2006 (PDF). FACES 2006 baseline report, Mathematica Policy Research, Inc., December 2008. (Available at www.acf.hhs.gov/)
• Trasande, L. How much should we invest in preventing childhood obesity? Health Affairs, 29(3): 372-378, 2010. doi: 10.1377/hlthaff.2009.0691
• Troiano, R. P., et al. Physical activity in the United States measured by accelerometer. Med Sci Sports Exerc, 40(1): 181-188, 2008. doi: 10.1249/mss.0b013e31815a51b3
• Wallinga, D. Agricultural policy and childhood obesity: a food systems and public health commentary. Health Affairs, 29(3): 405-410, 2010. doi: 10.1377/hlthaff.2010.0102
• Wang, Y. C., et al. Increasing caloric contribution from sugar-sweetened beverages and 100% fruit juices among US children and adolescents, 1988–2004. Pediatrics, 121(6): e1604-e1614, 2008. doi: 10.1542/peds.2007-2834

Health Affairs

• Table of contents from ‘Child Obesity: The Way Forward’ thematic issue (This issue is made possible with support from the Robert Wood Johnson Foundation)
• Child Obesity Policy Briefs
• Video and slides from the March 2, 2010 briefing

Related posts

• Kids and media use: Letting their fingers do the walking?
• 7 Simple tips to grow active, playful kids
• 12 Everyday Health Rules – From 1908

©2010 Kinetics. All Rights Reserved.

Dr. Marshall Nirenburg in his office with molecular models. He shared the 1968 Nobel Prize in Physiology or Medicine for his work on deciphering the genetic code. (I had the honor of working in the Laboratory of Biochemical Genetics at the National Institutes of Health, where Marshall is laboratory chief.) Photo courtesy of National Library of Medicine Profiles in Science.

Here’s a roundup of recent thought-provoking, amazing, and/or just plain cool items that are worth a look. In this week’s Nobel edition we celebrate the awarding of the 2009 Nobel Prizes.

Can you hear me now?
“Hello, you’ve won the Nobel.” A chat with Gunnar Öquist, the man who makes The Phone Call. From Seed Magazine.
“Then, the phone really started ringing. It was a reporter from The A.P. who said she was in front of our apartment and wanted to get a picture of me. I said, ‘I’m in my pajamas.’ She said, ‘That’s exactly the photo I want.’ I said, ‘But you’re not going to get it.’”  A brilliant interview with Martin Chalfie, 2008 winner of the Nobel Prize in Chemistry, who slept through The Phone Call. From The New York Times.

Sidewiki
Are you familiar with Sidewiki? If not, brush up with these thought-provoking posts.
Been Avoiding Social Media? It Just Kicked In Your Door, The Scholarly Kitchen
Google SideWiki: How to Brace Yourself for a Communications Bitch Slap, Phil Bauman
A Google colonial sideswipe, Andrew Keen of the UK Telegraph
Martin Frank, Executive Director of the American Physiological Society, points out via Twitter that Sidewiki could allow for commentary along side research articles. (@ExecDirectorAPS)
Make sure to watch the demo video and ponder the implications. What are your thoughts?

Stick figures
Watching life unfold as a social network where every link is a human relationship and every circle is a waistline. “The Buddy System: How Medical Data Revealed Secret to Health and Happiness,” from Wired. Includes stunning data visualizations.

4 billion served
“More than 4 billion [cell phones] are now in use worldwide, three-quarters of them in the developing world.” From The Economist special report on “The power of mobile money.”
4.1 billion SMS messages are sent daily, according to the latest Semi-Annual Wireless Industry Survey results from CTIA-The Wireless Association®

Art imitating life
Anatomical illustrations by Fernando Vicente that merge science and art and add a dash of fashion. They are reminiscent of Andreas Vesalius’s classic 1543 De Humani Corporis Fabrica (this link is to an amazing ‘touch and turn’ version of the book.)

Fat body = skinny wallet
NPR interview with Safeway Inc. CEO Steve Burd, about the company’s wellness incentive program. Employees receive a discount on their health insurance if their body mass index is below 30, the number over which people are considered obese. (Here’s a BMI calculator so you can see if you qualify for a discount.)

Don’t bother with the CliffsNotes
“There was no rule book, we just did what we thought was interesting and might prove fruitful. You can’t write a book on how to do that.” Dr. George Smith, 2009 winner of the Nobel Prize in Chemistry, in “‘Masters of Light’ Get Nobel,” a wonderful article in The Wall Street Journal.

©2010 Kinetics. All Rights Reserved.

Hand off – Courtesy of Anna.Hawaii at Flickr

Can simply swishing a carbohydrate-containing solution around in your mouth improve short-duration exercise performance? Yes, according to intriguing new research.

It’s been well documented that ingesting carbohydrates during exercise can improve athletic performance in events lasting for several hours or more. But in events lasting for only an hour, the carbohydrates you suck down aren’t needed by your muscles for fuel.

Surprisingly, however, consuming carbohydrates has been found to improve short, intense exercise performance. Since the carbs aren’t needed for energy by the working muscles, physiologists have been left scratching their heads. A key insight appears to be in how the carbohydrates are consumed.

From the lips to the hips
If individuals perform a simulated one-hour cycling time trial in a lab and are given glucose intravenously, bypassing the mouth and gut, their bloodstreams will fill with the energy-supplying sugar. Yet the subjects will show no improvement in cycling performance as compared to when they complete the time trial with an infusion of only saline.

However, if individuals perform a stationary cycling time trial in the lab and do nothing more than rinse their mouths with a maltodextrin solution, they’ll show an improvement in their exercise performance. Maltodextrin is a type of sugar that is not sweet — which offers another clue to this crazy paradox.

This evidence suggests it’s the mouth, not the muscles, that is happy to see carbohydrates. These results hint that there are taste receptors in the mouth that are sensitive to carbohydrates, even non-sweet ones such as maltodextrin. The theory is that once the receptors are activated, signals are sent to the brain that ultimately result in improved exercise performance.

A real tongue twister
As you might recall from science class, our tongues have taste buds for sweet, salty, sour and bitter. Our mouths now appear to also contain receptors that respond to carbohydrates. New evidence is provided in a nice set of experiments done by Drs. Ed S. Chambers, Matt W. Bridge and David A. Jones from the University of Birmingham and published in Journal of Physiology.

The researchers asked cyclists to perform a simulated time trial in which they completed a set amount of work in the shortest time possible. The participants were given a solution of 6.4 percent glucose, 6.4 percent maltodextrin, or water, which was the placebo. (As a reference, Gatorade is 6 percent carbohydrate, and regular Coke is 11 percent carbohydrate.) All three solutions included a noncaloric artificial sweetener (containing aspartame and saccharin) to make them indistinguishable from each other. The cyclists rinsed their mouths with one of the solutions at the start of the time trial and then approximately every seven minutes during the ride.

The cyclists completed the time trial 2 to 3 percent faster when they rinsed their mouths with the glucose or maltodextrin solution than with the placebo (60.4 minutes with glucose vs. 61.6 minutes with placebo in one experiment, and 62.6 minutes with maltodextrin vs. 64.6 minutes with placebo in a second experiment). There was a corresponding increase in power output during the faster ride, with no change in perceived exertion or heart rate. This indicates the sugar swishing lowered the participants’ perception of how hard they were working.

Your brain on carbs
The researchers next had individuals swish a carbohydrate solution in their mouths while undergoing functional magnetic resonance imaging (fMRI). The technology, which monitors the anatomical detail of brain activity, revealed that oral exposure to carbohydrates, both sweet and non-sweet, activates regions of the brain associated with reward. The areas include the striatum, the anterior cingulate cortex and the orbitofrontal cortex.

Before you start using Sprite as a mouthwash, there are several caveats to this research worth noting. The cyclists all performed the time trial following a six-hour or overnight fast, which is not how most of us start a bike ride or race. The concentration of some of the glucose and maltodextrin solutions used for the brain-imaging studies was almost three times greater (18 percent) than the one used during the exercise studies. The exact concentrations, types (glucose, fructose, maltodextrin, etc.) and forms (liquid, gel, solid) of carbs that are most effective in activating the brain to create more brawn are not known. These results also don’t reveal whether ingesting protein or other nutrients along with the carbs in a drink might alter the effects.

Elwood Gatorade Race. Courtesy of Alistair 35 at Flickr

The bottom line
Mounting evidence suggests we have receptors (both sweet and non-sweet) in our mouths that are sensitive to carbohydrates, and that when triggered, they activate areas in our brains associated with reward. This has implications for exercise performance and for the food industry. The research raises the intriguing question of whether other undiscovered receptors are lurking in our mouths as well.

By swishing a carbohydrate-containing drink in your mouth, you may be able to improve your exercise performance. If you are running a 5k or 10k race, or competing in a cycling time trial or other short-duration, high-intensity event, it may be worth your while to reach for a drink that contains carbs and to swish it around in your mouth. A potential 2 to 3 percent improvement in time is substantial. But if you need to slow your pace in order to swill, you may negate the improvement in time. And if you’re exercising in hot weather, be sure to swirl and then swallow the liquid in order to help stay hydrated.

Resources

• Carbohydrate sensing in the human mouth: effects on exercise performance and brain activity. Chambers ES, Bridge MW, Jones DA. The Journal of Physiology, Apr 15;587(Pt 8):1779-94, 2009.
• Historical Perspective of Biomedical Imaging: From MRI to fMRI

Related posts

• Are humans designed to be endurance runners?
• What can pro cyclists teach us about pain?

©2010 Kinetics. All Rights Reserved.

Do you have a garage full of ThighMasters, Ab Flyers, Ab Circles, Ab Coasters and Ab Rockers? Are you concerned about thunder thighs, love handles, man boobs, saddlebags, potbellies or cankles?

Everyone has his or her problem area (or areas). Thanks to the concept of spot reduction, we’ve witnessed decades of fabulous (or should that be flabulous?) gizmos such as the Astro-Trimmer, Abflex and, of course, those classic vibrating belts.

What can you do about those flabby arms or muffin tops? Does spot reduction work? Here are answers to the top six most common questions.

1. What is spot reduction?
Spot reduction is the idea that you can lose fat from a specific part of your body, especially if you exercise the area. Some people think spot reduction means that when you exercise a particular area, the fat in that area will turn to muscle. Unfortunately this is not medically possible — it would be like turning oranges into apples.

The concept of spot reduction also implies that the muscle tissue and fat tissue in a particular part of your body engage in some sort of metabolic pillow talk with each other. For example, if you do sit-ups, then ideally, your abdominal muscles would selectively use the fat that blankets them for energy. Although many cells communicate with each other in numerous intimate ways, there’s still a language barrier in this regard.

2. Can you spot-reduce?
No. If spot reduction worked, there would be a lot of lopsided people walking around. Think of anyone who uses one side of his or her body or one limb much more than the other side. Pitchers, quarterbacks and trombone players come to mind. If spot reduction worked, a player’s dominant arm would have much less fat than his or her opposite arm.

Tennis players are a perfect example. In a classic study, researchers examined the arms of players. Although the dominant arm had a greater girth due to more muscle mass than the opposite arm, there was no difference in skinfold fat thickness between the arms. For further proof, researchers asked a group of individuals to do a total of 5,000 sit-ups over 27 days. (That’s about 185 sit-ups a day.) Fat biopsies were taken from the participants’ abs, buttocks and upper backs before and after the exercise program. The fat decreased the same amount in all three areas, demonstrating that no spot reduction occurred.

3. What is fat and what is it good for?
Fat is made up of individual fat cells called adipocytes. They are just one type of cell, along with muscle cells, nerve cells, bone cells, liver cells and numerous others. A person’s total number of fat cells is thought to be determined by puberty. After that, as you gain and lose weight, the size of these cells swells or shrinks.

Some fat is good. Odds are you are either sitting on fat (your tush) or standing on it (padding in your feet) as you read this. Fat protects your internal organs, serves as an energy warehouse, insulates and helps regulate body temperature. Fat cells secrete numerous proteins and hormones that can influence blood pressure, immune function and blood sugar (glucose) levels.

4. Can you control the location of your fat?
Fat is like real estate — we’re all concerned with location, location, location. And location is mainly determined by the two G’s: gender and genes. To verify this, take a good long look at your parents and siblings, and then take a good long look at yourself in the mirror. Scary, isn’t it?

5. Does location matter?
Ab-solutely. There’s a growing body of scientific evidence that links the location of your fat to your health. Fat tends to be located either around the middle or center of the body (the classic apple shape) or peripherally on the arms, hips, and thighs (pear shape). Studies continually show that people with apple shapes are at much greater risk than those with pear shapes for numerous conditions, such as heart disease, type 2 diabetes and liver disease.

6. Can anything be done about thunder thighs and beer bellies?
The great news is yes, you may be able to shore up an area. And if you can reduce belly fat, you may decrease your risk of associated health problems. But it’s not as simple as using products that you’ve ordered on late-night TV for eight minutes a day. It takes a little bit of sweat combined with good nutritional habits. Repeat after me this mantra we all know by heart (and need to take to heart): Move more, eat less.

The first step is to engage in regular physical activity, especially as outlined in the new Physical Activity Guidelines. Engage in some type of strength training two or more days a week. You’ll tone up your muscles, strengthen your bones and burn calories. Buffing up your muscles, however, won’t help if you still have a layer of fat providing a cloak of invisibility over them.

So the companion step is to divest yourself of your extra pounds by also engaging in regular moderate-to-vigorous endurance (aerobic) activity at least 60 to 75 minutes a week. Lastly, keep an eye on what you eat. You know the drill: Burn more calories than you consume.

Your muscles require fuel to work, and fat is a great source. When you exercise, chemicals are released in your bloodstream that travel to fat cells and trigger them to break down units of fat to be burned for energy. Unfortunately, we can’t control which fat cells respond to the chemical signals. However, a general rule of thumb seems to be “last in, first out.” That is, wherever you’ve most recently added the insulation is generally the first place it’s lost. Then eat in moderation so that you aren’t refilling your fat cells to overflow.

What gizmos do you have in your garage? What late-night infomercials made you pick up the phone? Did you use any of the gadgets more than once? Some of these items can legitimately be incorporated into your exercise routine, while others probably need to be sprung during spring cleaning, sold at a yard sale or put up for adoption on eBay.

©2010 Kinetics. All Rights Reserved.

Kinetic
ki•net•ic  adjective
Of, relating to, or produced by motion.
Moving or causing motion; motory; active, as opposed to latent.

Our bodies are in perpetual motion, from the winding and unwinding of our coiled DNA to the beating of our hearts and accelerating of our limbs. This blog explores, debates and celebrates the body as we sense, move and adapt. I hope to inspire you to learn, argue, embrace, question and move.

©2010 Kinetics. All Rights Reserved.