Poor weight gain: a cautionary tale

May 15, 2005 06:24 · 1251 words · 6 minute read

Weight gain is one of a number of things that pediatricians think about when they’re looking at the overall health and development of your child. This article is a cautionary tale, because well-meaning pediatricians may, when looking at weight gain, not be giving you the best advice.

Since I’m going to ramble on a bit and provide links to things that back up what I’m going to say, I’ll sum this up for those who don’t want to read the whole thing:

  • Any time your pediatrician (or any doctor, for that matter) expresses concern about something, it pays to become informed about that topic. The experts that we rely upon are not infallible. The internet is your friend.

  • The converse is also true: any time you have a concern about something and your doctor doesn’t, it still pays to do research.

  • “Poor weight gain” and “failure to thrive” are two concerns your child’s pediatrician may have. If your child is breastfeeding, there’s a significant chance that this may be an incorrect diagnosis.

As with many fields, medicine is very complex and rapidly evolving. I’m a computer programmer, and it’s impossible for me to keep up with everything that goes on in my field. That’s where specializations come in. I have the aptitude to handle a wide variety of technical problems, but my deep familiarity is with certain bits of technology. Likewise, a doctor has a specialty, such as pediatrics, that allows them to focus on the needs of that particular group of patients.

When it comes to health, the complexity of the human body means that there’s a fair bit of uncertainty. People have to go with their opinions, experience and intuition until real scientific data shows up.

Around the time that I was born, breastfeeding was extremely unpopular. About 75% of babies born in the US were fed formula. That was a case of people going on advice that turned out to be bad. We now know that breastmilk is by far the best source of nutrition for a newborn. The US Center for Disease Control (CDC) now recommends breastfeeding for at least a year. The World Health Organization (WHO) recommends breastfeeding for at least two years.

Anecdotally, I just heard (firsthand) of a mother who was told by their pediatrician to feed their baby formula at two days. Medical advice cannot be much farther from current research than that.

Back to the point, though: back in the ’70s, forumla feeding was the norm in the US. It was in this environment that the CDC first produced its growth charts. What difference does that make? Formula is based on cow’s milk. If you take a look at a cow, you’ll notice that it’s a whole lot bigger than a human, but not very smart. A baby that’s fed formula is getting the proteins and hormones that drive cow growth, not human growth.

It’s not a big leap to think that this would result in a different growth pattern between formula-fed babies and breastfed babies. In fact, a study published in 1992, “Growth of breast-fed and formula-fed infants from birth to 18 months (the DARLING study)” (Dewey, et al) showed that very trend. Breastfed babies actually gain more initially and then formula fed babies pull ahead. Formula fed babies weighed a pound more at 12 months than their breastfed counterparts. After 18 months, the difference starts to disappear.

So, the CDC revised their charts in 2000 to include more breast-fed babies. While that revision reduces the skew somewhat, you still end up trying to measure the growth of breasfed babies against the growth of formula-fed babies. A study published in 2003 showed that the CDC growth charts don’t accurately depict the growth trend of babies that are fed following the international feeding recommendations.

If a doctor is following the CDC growth charts, it’s easy to see how they could come to a “poor weight gain” conclusion for a baby that’s really just following the trend for how they are raised. The World Health Organization recently found that pediatricians may have caused unnecessary concern about breastfed baby weight gain because of the discrepancy in the charts. The linked BBC article also mentions that overfeeding of babies could be part of the reason why the adult population is getting fatter. A report published in The New England Journal of Medicine states that the current generation of children in America may be the first to have shorter life expectancies than their parents.

Many pediatricians and books talk about starting solids between 4 and 6 months of age, though some books talk less in terms of age, and more in terms of developmental milestones. The WHO recommends exclusive breastfeeding until 6 months of age. Starting solids too early can increase the chance of food allergies. We started Crysania at 5-12 months, and that was probably too early for her.

At Crysania’s 1 year pediatric appointment, her doctor raised the concern that her weight had “leveled off”. At her previous appointments, she had been gaining in percentiles, and at that one she had dropped. It turns out that this was the normal pattern for breastfed babies, as the WHO charts coming out later this year show.

Had we done research then, we would likely have learned this and would have reacted cautiously. Instead, we reacted by introducing a whole bunch of foods that we would not have likely introduced otherwise. Between August 2004 and April 2005, Crysania’s weight gain was slow and erratic. This despite the fact that we were trying all kinds of foods and re-trying foods that she seemed sensitive to.

She seemed to be tolerating egg yolks well, so we were giving that to her every day. In December, at her pediatrician’s recommendation, we took her for an allergy test. That was a good move, because she tested positive for allergy to eggs. Many children have sensitivities that they grow out of, so this was a good thing to know.

She tested negative for dairy allergy, so we tried all kinds of dairy with her again despite various reactions that it seemed to cause. It’s worth noting, however, that the allergy blood test has a 15% false negative rate. It would appear that Crysania fell into that 15%. We closely tracked different foods that we introduced, and found that between mid-March and mid-April, Crysania had been having dairy every day. During that period, she lost 8 ounces. Her pediatrician was recommending blood tests to see if there was some serious problem. Instead, we stopped dairy altogether.

In the first dairy free week, she gained 10 ounces. Since then, she has been gaining steadily 1.5 to 2 ounces per week. For her, dairy caused a serious loss of appetite and constipation. We had tried lactose free products, but they didn’t help, so it would appear that she has a dairy allergy.

We had seen reactions to dairy earlier. Had we not been as concerned about her weight gain, we would have just held off on dairy for a longer period of time. Her weight gain would likely have been better.

True poor weight gain can be a sign of a serious problem, so it’s worth considering the issue seriously. But, it’s good to know if there truly is a weight gain problem, or if you’re really just seeing the effects of skewed data. I’m hoping that the links I’ve provided in this article will help others make good choices concerning their babies’ weight gain.