Good news! Preschoolers are less likely to be overweight!

Earlier this week,  a paper was published in the Journal of the American Medical Association (JAMA) reporting the prevelence of obesity in the United States from 2011-2012. The Centers for Disease Control and Prevention (CDC) collects information from people all over the country and reports their findings every other year. These data are widely used in everything from news stories to policy documents to grant proposals. If you've ever heard someone say "In the United States, one-third of all adults are overweight or obese" chances are she was referring to these data.

In this most recent report, there was some exciting news! Although obesity rates didn't change much in most of the age groups, there was a significant decrease in the number of preschool-aged children who were classifed as overweight, from nearly 14% in 2003-2004 to 8.4% in 2011-2012.

There is so much work going into the prevention of childhood obesity at local, state, and national levels and this report shows that these efforts are having an impact. While nearly 10% obesity  among preschool children is far from desirable, it is good news that we are finally reversing course on such a challenging and devastating public health issue.

Reference: Ogden CL et al. Prevalence of Childhood and Adult Obesity in the United States, 2011-2012. JAMA. 2014; 311: 806-814.

In the News: Early Solid Foods and Obesity Risk

A few weeks ago, we talked about findings from a large study about increased obesity risk with putting babies to sleep with a bottle. This time, we’ll share another outcome from that same study related to early solid food introduction. They found that introducing solid foods before four months of age increased obesity risk by 40 percent, and this was not the only study with this finding. (Gibbs 2013) In a past post, we shared a 2011 study indicating  that there was a 6-fold higher risk of obesity at 3 years when infants were started on solid foods before 4- months of age. This risk, however, was only seen in infants that were formula fed or fed breast milk for less than 4-months.

The American Academy of Pediatrics and World Health Organization continue to recommend that parents wait until 6-months of age to start solid foods with their infants. However, many parents start solid foods earlier than this. In the Gibbs study, 29% of formula fed infants and 9% of breastfed infants started solids before 4-months of age.

There are many reasons parents start solid foods earlier than the recommended 6-months of age. According to a study reported on in a past post, top reasons for starting solid foods included:

• Thinking that the baby seemed hungry
• Wanting to feed something other than formula or breast milk
• Wanting the child to sleep longer
• Having a healthcare professional tell the parent to start solids earlier
• The baby wants the food that the parent was eating

If you're feeling tempted or confused, please read this past post for tools to help you deal with each of these common reasons for starting solids early.

The Gibbs study explores some common feeding practices and we know that their findings and recommendations may challenge your current practices. For more information about why it’s important to wait until about 6-months to start solid foods and how to know when your baby is ready, click here. When did you start solid foods with your baby and why?

Reference
Gibbs BG, Forste R. Socioeconomic status, infant feeding practices and early childhood obesity. Pediatr Obes. 2013 Apr 2. [Epub ahead of print]

Baby Behavior in the News: Spoon-feeding vs. Finger-feeding and Obesity Risk

With all of the buzz around obesity prevention in the US, you may have seen this in the news recently: claims that babies starting pureed solid foods (referred to as traditional spoon-feeding) first are more likely to be obese compared to babies whose first tastes of solid foods were finger foods (also known as baby-led weaning). Here are just a few of the headlines you may have encountered: "Babies Fed on Solid Foods Less Likely to be Obese"; "Solid ‘Finger Food’ May Help Babies Avoid Obesity"; and "Giving Babies Finger Food Could Stop Obesity." Today we will take a look at the study behind the headlines and explain why the the results of the study are overblown in the media.

The Study: Baby knows best? The impact of weaning style on food preferences and body mass index in early childhood in a case–controlled sample

155 parents of children between 20-78 months of age were given a questionnaire asking about their children’s feeding styles, starting solid foods, food preferences and consumption patterns, whether or not the child was considered a “picky eater” and the child’s height and weight. This was a cross-sectional study, meaning that the questions were asked at one point in time, and in this case, the answers to the questionnaires were compared between 2 categories of infants, those who were “spoon fed” vs. “finger fed” their first solid foods (referred to respectively as traditional spoon feeding and baby-led weaning in this study). Specifically, baby-led weaning refers to babies who are fed their first tastes of solid food via finger feeding or self-feeding. Traditional spoon feeding refers to babies who receive their first solid foods from a spoon (parent-initiated).

When these 2 categories were made, 63 children remained in the spoon fed group and 92 in the finger fed group. All of the health information gathered via questionnaire was then compared based on these 2 categories. The researchers were interested in seeing if children who started solid foods via either spoon feeding or finger feeding were more likely to be overweight or picky eaters.

The Study Results

There was no significant difference in BMI between babies in the spoon fed vs. finger fed group (10 spoon-fed children were above a healthy weight compared to nine in the finger fed group). There was a difference in the number of babies in the obese category, with 8 babies in the spoon fed group obese and no babies in the baby-led group obese. Three babies in the baby-led group were underweight and no babies in the spoon fed group were.

Study Limitations: What does all this mean?

While it does make sense that self-feeding, such as finger feeding, might result in better self-regulation of food intake compared to spoon feeding in which the parent is in charge of the feeding, this study was not designed to support this hypothesis. Cross-sectional studies only provide information about a snapshot in time, in this case provided via parental reports of infant feeding and health. Because this is not a randomized controlled trial, we cannot know for sure if finger feeding your baby first, as opposed to spoon feeding, actually leads to healthier weights and food choices.

Other limitations of this study include its small sample size and the majority of the sample itself had normal weights and longer than average breastfeeding durations. Babies in the finger-fed group were breastfed on average 23 months, more than double that of the spoon-fed group (9.5 months). The association between breastfeeding and obesity could have impacted the results of this study as well.

Bottom Line

We would need larger studies with different designs to be able to make a strong statement about which method of feeding baby’s first food results in better health outcomes. Also, knowing that every baby is different and developmentally ready for new food textures at different ages, it’s hard to make one conclusion as to what is best for all babies. So for now, the original guidelines for starting solid foods still apply: for the specifics, read our post Starting Solid Foods: It’s Worth the Wait. You can also take a look at another related news flash we posted entitled: Breastfeeding and Later Solid Food Introduction are Protective against Obesity in Young Children.

Reference
Townsend E, Pitchford NJ. Baby knows best? The impact of weaning style on food preferences and body mass index in early childhood in a case–controlled sample. BMJ Open 2012;2:e000298.

Poor Infant Sleep does not Increase Later Obesity Risk

By Jennifer Goldbronn, MAS, RD

With childhood obesity rates at epidemic levels in developed countries around the world, there is great interest in identifying successful interventions to decrease obesity risk. Recently, researchers have suggested a potential association between poor sleep and later obesity risk. Today we’ll discuss this potential association and present information from a new study examining the association between improved sleep in infancy and obesity risk at age 6 years.

In a previous post we wrote about a research article linking short sleep duration to increased risk of obesity. (Bell 2010) In this study, the association found was not specific to infants because the authors grouped together kids of all different ages.

Sleep and Obesity: Why the Link?

Despite all of the research about the relationship between sleep and obesity, there is no evidence showing a cause and effect relationship. Researchers have theories for the associations they’ve found, including: (1) if children are sleeping less, their bedtimes may be later allotting them more time to take additional calories in the evening or (2) children may be less physically active because of fatigue from shorter sleep duration. Unfortunately, at this time, these explanations are just speculation and while some studies have shown associations between BMI and chronic short sleep in older children, none have focused on how sleep in infancy may or may not affect later risk for obesity.

The Study

In a recent Australian study, providing education to parents of infants with parent-reported sleep “problems” at 7-8 months resulted in improved infant sleep organization but did not reduce obesity risk at age 6. (Wake et al. 2011) A Sleep “problem” was identified by asking 2 questions: (1) “Over the last 2 weeks, has your baby’s sleep generally been a problem for you? (yes/no)” and (2) if yes, the parent rated the severity of the problem on a 7-point scale with 1-2 mild and 5-7 severe.

The Study Intervention

Nurses were trained to provide a short sleep education to parents at the 8-month well-child check-up. Topics discussed included normal infant sleep patterns and sleep problems and potential causes. Nurses helped parents to identify possible solutions and created an individualized sleep management plan for each family. Mothers were asked to complete a 2-week sleep diary and to choose one of two sleep strategies: “controlled crying” or “camping out.” Mothers also attended 1-2 follow up sessions with the nurse where sleep patterns and improvements were identified and new goals were set.

The controlled crying strategy involved parents responding to their infants’ cries at increasing time intervals to allow the infant to learn to self-soothe. (see note below) Parents choosing the “camping out” strategy were instructed to initially stay with the infant while he or she fell asleep, slowly moving farther away over the following days, until the infant could fall asleep without the parent nearby.

Results of the Intervention

Parents in the intervention group reported fewer infant sleep “problems” at 10 months (56% vs. 68%) and 12 months (39% vs. 55%) compared to control groups. Intervention parents also reported fewer and shorter night-wakings than control parents. However, sleep duration was similar in both groups.

Although the sleep intervention did decrease parent-reported “sleep problems” and night wakings, there was no effect of the intervention on obesity at age 6. Both intervention and control groups’ BMI and waist circumference were similar. After the study was completed, the researchers looked back at the data to see if there was any association between childhood sleep duration and BMI. They found no association between sleep duration at 7, 10, 12 months or 6 years with obesity at age 6.

The Bottom Line:

According to recent data, your baby’s sleep patterns at night will likely not affect his risk of obesity in later childhood. We know (from experience) that some of you may be very tired right now and hoping for a solution to help your baby sleep better. Our best advice: know what to expect from your baby’s sleep patterns by reading our posts about how sleep patterns change with age and learn some ways to get yourself a little more rest.

Remember, you can’t change the rate at which your baby’s body matures and learns to sleep for longer stretches, but you can change how you react to it! Arm yourself with the knowledge and know that this too shall pass.

Note: We are not advocating letting your baby cry! We are simply reporting the methods used by the authors of the referenced study. Also, it is important to note that this intervention was carried out with older infants, ages 8-10 months; most infants this age have the ability to sleep a 6-8 hour stretch at night, but they may wake if they need something or to practice their new found motor skills.
While we do not advocate parents letting their babies cry for long periods, also known as the “cry it out” approach, parents of older babies can encourage them to learn self-soothing skills. For example, putting your baby to sleep in his crib drowsy, but awake may help him learn to soothe himself to sleep. However, keep in mind that, in a separate study, only about half of 12 month olds were able to self-soothe after awakening during the night. The other half needed their parents’ help to get back to sleep. (Burnham et al. 2002)

References
1. Bell J, Zimmerman F. Shortened Nighttime Sleep Duration in Early Life and Subsequent Childhood Obesity. Arch Pediatr Adolesc Med 2010; 164: 84-845.
2. Wake M, Price A, Clifford S, Ukoumunne OC, Hiscock H. Does an Intervention that improves infant sleep also improve overweight at age 6? Follow-up of a randomized trial. Arch Dis Child. 2011;96:526-532.
3. Burnham MM, Goodlin-Jones BL, Gaylor EE, Anders TF. Nighttime sleep-wake patterns and self-soothing from birth to one year of age: a longitudinal intervention study. J Child Psychol Psychiatry. 2002;43(6):713-25.

News Flash: Breastfeeding and Later Solid Food Introduction are Protective against Obesity in Young Children

A 2007 report from the CDC showed that 3 out of every 4 new mothers in the United States initiate breastfeeding. However, only 33% are exclusively breastfeeding at 3 months. That means 64% of babies nationally are at least partially formula-fed. (1) A 2011 study, that received widespread news coverage, now shows that formula-fed babies are at higher risk of obesity at age 3. Among those that are formula-fed and started on solid foods before 4 months of age, the risk of obesity at age 3 is even greater. (2)

Recommendations vs. Reality
Currently, 26% of infants in the US are introduced to solid foods before 4 months-of-age and, while the World Health Organization (WHO) and the American Academy of Pediatrics (AAP) Breastfeeding Section recommend introduction of solid foods at 6 months of age, many pediatricians (and even the AAP Committee on Nutrition) continue to endorse starting solids between 4-6 months of age. However, a recent study may provide more proof that starting solid foods before 4 months of age could have negative effects lasting into early childhood. (2)

Pediatrics recently published the results from a large study conducted at Harvard that compared age of solid food introduction (less than 4 months, 4-5 months or ≥6 months) and risk of later obesity in preschoolers. (2) Sixty seven percent of infants in the study were “breastfed” (defined as at least partly breastfeeding) at 4 months-of-age and 33% were “formula-fed” (defined as never breastfed or breastfed less than 4 months). Two factors were linked to increased obesity risk at age 3:

1. Early solid food introduction among babies who were never breastfed or were breastfed for less than 4 months - Those introduced to solids before 4 months-of-age had a 6-fold increase in odds of obesity at 3 years-of-age. Interestingly, early introduction of solid foods in babies who were at least partly breastfed for more than 4 months had no effect on later obesity, and moms who “breastfed” for longer than 4 months were less likely (8% compared to 33%) to start solid foods early compared to “formula-fed” babies and babies who breastfed less than 4 months. (2)

2. Breastfeeding Status - Breastfeeding status was also connected to obesity at age 3 years, with almost double the percentage of “formula-fed” babies obese compared to babies breastfed at least 4 months. (2)

What does all of this mean?
With 1/4 of babies in the US never breastfed and 1/2 breastfed for less than 4 months, delaying solid food introduction until after 4 months-of-age may be an important step towards decreasing obesity in young children. (2) Other studies also indicate that introduction of solid foods before 4 months of age is associated with rapid weight gain in infancy and higher body fat or weight in childhood. (3,4) Also, breastfeeding, even partly, for at least 4 months may be protective against early childhood obesity. (2) This is not to say that babies don’t reap added benefits when exclusively breastfed (such as reduced risk of gastrointestinal and respiratory illness, Sudden Infant Death Syndrome (SIDS) and allergies, to name a few)! (5) However, this particular study only compared breastfed (at least partly breastfed for at least 4 months) to formula-fed (breastfed less than 4 months or fed only formula) infants.

It’s also important to note that while it is recommended to delay solids until close to 6months-of-age, developmental signs of readiness for solid foods must still be observed in the infant before solid foods are introduced. For more information about what developmental signs to look for and which foods to feed first, click here.

Next time: Baby Behavior during illness

References:
1. CDC Breastfeeding Report Card –– United States, 2010. Web. 28 Mar. 2011.
2. Huh SY, Rifas-Shiman SL, Taveras EM, Oken E, Gillman MW. Timing of Solid Food Introduction and Risk of Obesity in Preschool-Aged Children. Pediatrics. 2011 Mar;127 (3):e544-51.
3. Baker JL, Michaelsen KF, Rasmussen KM, Sørensen TI. Maternal prepregnant body mass index, duration of breastfeeding, and timing of complementary food introduction are associated with infant weight gain. Am J Clin Nutr. 2004;80(6):1579-88.
4. Kim J, Peterson KE. Association of infant child care with infant feeding practices and weight gain among US infants. Arch Pediatr Adolesc Med. 2008;162(7):627-33.
5. Kramer MS, Kakuma R. The Optimal Duration of Exclusive Breastfeeding: A Systematic Review. WHO, 2002.

Slight Detour - Does Nighttime Waking Make Babies Fat?

We interrupt our blog posts on multiples to give you this special post.... Ok, maybe I'm being a little silly but I have had several people send me links to press coverage on an article that was published recently in the Archives of Pediatrics and Adolescent Medicine. Because the misinterpretation of the article could result in parents being confused or concerned, I thought we would provide our readers with our own take on this article.

The Article: Shortened Nighttime Sleep Duration in Early Life and Subsequent Childhood Obesity by Drs. Janice Bell (University of WA, Seattle) and Frederick Zimmerman (UCLA). Arch Pediatr Adolesc Med 2010; 164: 84-845.

Summary: The authors conducted a secondary analysis (meaning they used data already made public to look at something they were interested in) of a US government funded study that, in part, asked families in 1997 and again in 2002 to use time-diaries to record their children's sleep habits. Infants and children in the study were also measured (weight and height) at follow up. The final sample included 822 children who were between 0-59 months and 1108 between 60 to 154 months of age in 1997. They found that children in the younger group (0- 59 mo) with a short duration of nighttime sleep (in the bottom 25%) at baseline had a greater chance of becoming overweight or obese by 2002. This was not found in the older group. Daytime napping did not seem to make a difference.

The Media "Take": I've seen the press coverage from more than 2 dozen news agencies and blogs; most seem to give the impression that infants and children should be sleeping 13 to 14 hours at night in order to reduce the risk for obesity. They don't account for differences in sleep patterns in infancy vs. preschool children.

The Problem: The researchers grouped the children into the 2 groups for statistical and practical purposes (we don't know how many children in the study group were less than 1 year of age) but doing so was not clinically appropriate. I'm sure that the researchers would not say that parents should worry if their newborns sleep less than 10 hours at night. As all of our readers know, newborns and young infants need to wake for many reasons and that while they will sleep a total of 13 or 14 hours, it won't be all at once.

The Reality: The researchers put a whole bunch of kids (from newborns to 4-year-olds) in a big group and found that sleeping more than 10 hours at night was associated with a reduced odds of being overweight later on. Having this "association" does not mean that less sleep causes kids to become heavier. The authors were not able to control for a lot of things that might have made a difference in the children's weight status. More importantly, putting kids with such different expectations for sleep in one big group isn't useful, especially when it confuses parents and reporters. It would have been better to put the infants in a separate group. But of course, the researchers didn't ask me.

I hope this helps you understand this study a little better.

Next time: Back to Twins!