The prevalence of obesity in children is increasing. Is this biasing the growth charts that physicians use to assess normal growth? In other words are children that would have been in the 50th percentile before the rise in childhood obesity now in a lower percentile?

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    Who cares! Comparing your child against standards such as these is a distraction from the real concerns. Is the child healthy? Is the child growing? Is the child making progress?
    – tomjedrz
    Commented May 9, 2012 at 5:27
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    @tomjedrz-- these charts help you to define if the child is healthy; that's their purpose. If the child is that much below the median size, then there could be a nutrition problem.
    – mmr
    Commented May 9, 2012 at 19:26
  • here better site i found for calculating growth charts and u can also register your data . followchilds.com
    – goodmood
    Commented Jan 14, 2013 at 17:43

3 Answers 3



You can read more about growth charts here. Here's a quotation about their creation:

The 2006 WHO growth curves for children are based on data from the WHO MGRS, a study conducted during 1997--2003 in six sites: Pelotas, Brazil; Accra, Ghana; Delhi, India; Oslo, Norway; Muscat, Oman; and Davis, California (12). The criteria for selection of the communities included 1) socioeconomic status that does not constrain growth of the child (based on infant mortality rate; prevalence of underweight, stunting, and wasting; subpopulation size; and access to safe water), 2) low altitude (<1,500 m [4,921 ft]), 3) low enough population mobility to allow for a 2-year follow-up, 4) at least 20% of mothers in the community willing to follow international feeding recommendations, 5) existence of a breastfeeding support system (typically in the form of lactation consultants), and 6) existence of a research institution capable of conducting the study (12). The international infant feeding recommendations in effect at the time of the study included exclusive breastfeeding for at least 4 months (although predominantly breastfed infants were also included in the study), introduction of complementary foods by at least 6 months but not before 4 months, and continued breastfeeding for at least 12 months. Study participants were provided breastfeeding support as needed and were counseled on complementary feeding, with an emphasis on timing, energy density, feeding frequency, and micronutrient content.

In addition to the breast feeding requirements, there was a straight cutoff for abnormally large children in relation to height:

Weight-for-length measurements of >3 standard deviations from the overall study median were considered to be outliers and excluded from the final sample....To eliminate the effect of overweight children on the weight distributions in the WHO curves for children aged 24--59 months, weight measurements of >2 standard deviations above the study median were excluded; a total of 226 (2.7%) weight measurements were excluded.

They did a pretty thorough job of making sure that those growth charts have a great deal of scientific backing to them, inasmuch as these charts define 'normal' and 'healthy' for the world's children.

  • "... inasmuch as these charts define 'normal' and 'healthy' for the world's children." And that is the reason that obesity won't skew the charts: it's "healthy" and not "typical." (Excellent link, mmr!)
    – Will E.
    Commented May 9, 2012 at 13:29
  • This is a great answer, but the question still begs the statement that these charts should be used as a general measure. There are many ways to determine the health of a child and where they fall compared to others is not always the best measure no matter how well the chart is created. Nutritional Foods, lots of movement, play and exercise will do much more to ensure a child is healthy than over-considering where they fall on a growth chart. Commented Jan 14, 2013 at 18:09
  • You seem to focus on the WHO growth charts, but the US CDC releases their own, and they have a different methodology (available on the same page).
    – kojiro
    Commented Jan 31, 2013 at 13:20

If anything, it makes kids of today show higher on the charts than they would be if a new sample was run for the charts today.

The greater concern, and one that I have heard some parents say loudly and proudly, is that their kids are in the 99th percentile. By comparing the size of their child now to children of approximately 10 years ago, in some cases they are much larger, due to obesity. However, when you look at them in comparison to other children they don't appear to be much larger. One personal observation: Our kids are at about the 75th percentile and they look very skinny by comparison to their peers. However we know them to be healthy/active children. You should also be more concerned with how their height relates to their weight. If they are in the 25th percentile of height...and 99th percentile of weight, it is likely they are heading for a serious problem (barring any extenuating circumstances, like growth issues).

  • I'm having trouble finding a reference to support this (still looking), but I believe there is a difference between being in the highest percentiles for weight as a infant/toddler vs. later. For an infant, a parent commenting proudly that the child is in the 99th percentile is more of a declaration of health than anything else.
    – user420
    Commented May 11, 2012 at 14:24
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    For a personal anecdote: my son has always been at the 95th percentile for height AND weight. He was 4.4 kg at birth, and he's 4 years old now and at the 97% for both. He's 110 cm tall and 22.5 kg. I don't see it as a declaration of health - more like a warning that once his teenage years are here, I'm going to need an extra fridge to keep his food in if he continues to be on the top of the curve.
    – Darwy
    Commented May 13, 2012 at 0:03
  • @Darwy My youngest is similarly sized and with 3 boys (one girl who is fairly small), I'm pretty sure we will have the same concern as far as stocking food. Commented May 14, 2012 at 20:18
  • @Beofett When the 5 year old has fat rolls on his arms, and they continue saying that, it is not a statement of health. It is regrettably ignorance on what they are allowing their child to consume. Commented May 14, 2012 at 20:18
  • @AnthonyPotts Please read what I said. A 5 year old is not a toddler, and definitely not an infant.
    – user420
    Commented May 14, 2012 at 20:39

One of the purposes of the WHO Growth chart is to set a standard percentile ranking to identify the actual weight whether the child is considered obese and or underweight. The figures are already set as a standard. For you to be able to get the percentile ranking of the child, it is best a baby use a baby weight percentile calculator, so you would know the rank of the child based on WHO standards. The obese children are already classified based on their weight. The number of obese children is not a dependent variable in the percentile ranking.

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