My Book – The Science of Mom – is Available for Pre-order!

Imagine my surprise when, last week, my editor at Johns Hopkins Press emailed me to ask that I check over the Amazon page for my book. What? There’s an Amazon page?! As far as I knew, my book wasn’t coming out until the fall. I did a search for my name and book title on Amazon, that great vault of hundreds of thousands of books, this is what I found:

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I guess this is really happening, dear readers! And it’s happening sooner than I thought. The book will be released on July 2, and it’s available for pre-order now!

science of mom coverThis is super exciting but also terrifying at the same time. It means that some people might actually read my book. They might like it or they might not, and that’s just the way it is. I hope you read it and like it, though. I would not have had the motivation or courage to write this book if not for all of you – smart people who read my blog and comment on it. You showed me that there are other parents out there, like me, who are curious and want to know more about the science of parenting. You showed me that tone matters – that if we are going to communicate and support each other, we have to start from a place of respect for each other. You showed me that our stories matter, and that nuance is important. As I dug into the science of parenting decisions, I found examples where science gives us a clear course of action but just as many where the science is so murky that we are left to follow our hearts, well-informed as they may be, and hope for the best.

Another surprise when I scanned through my book’s Amazon page for the first time was the reviews. I hadn’t seen these yet, and they brought tears to my eyes. What I was trying to do with this book came through to these readers, and that made me so happy. Here’s what several wonderful folks had to say about my book:

Finally, someone has brought some science—and some sense—to the mommy wars. Should be required reading for all new (and old) parents. 

~Emily Oster, Brown University, author of Expecting Better: Why the Conventional Pregnancy Wisdom Is Wrong—And What You Really Need to Know

 

Alice Callahan has written a breakthrough book, combining the compassion, warmth, and angst of a mother with the measured reasoning of a scientist. She helps parents not only understand how science works, but how they can access that science to answer their questions. She’s found a way to access the scientist in all of us.

~Paul A. Offit, MD, The Children’s Hospital of Philadelphia

 

Yes! An easy-to-read, fascinating, nuanced review of the science behind new parents’ biggest health questions. Many of these issues—infant sleep, breastfeeding, vaccines—have or will hit your ‘Should I panic?’ button. With gentle guidance, Alice Callahan puts your fears to rest.

~Tracy Cutchlow, author of Zero to Five: 70 Essential Parenting Tips Based on Science (and What I’ve Learned So Far)

 

Too many of today’s parents treat science as a weapon, using it to justify some choices and condemn others. Yet, most don’t fully understand what science can and cannot tell us. By giving parents a comprehensive understanding of how science relates to parenting, Alice Callahan has helped us turn this weapon into a tool for peace. Callahan untangles basic scientific concepts, reveals the realities and limitations of research, and advocates for a measured approach to parenting science that eschews absolutes and acknowledges nuance. The Science of Mom is a rare gem in the parenting canon—smart, sensitive, and a lifesaver for a generation of parents caught in the nebulous spider’s web of Internet ‘wisdom.’ 

~Suzanne Barston, author of Bottled Up: How the Way We Feed Babies Has Come to Define Motherhood, and Why It Shouldn’t

 

Families routinely search for health information. The Science of Mom makes it easy collecting evidence for health decisions and putting it into perspective with a mom-to-mom connection. Callahan’s advice is thoughtful, backed by science and feels fueled of love. She is willing to provide powerful advice when detailing the science and safety of vaccines. Keep this book in arm’s reach as you support your infant for calm and direction. 

~Wendy Sue Swanson, MD, MBE, FAAP, Seattle Children’s Hospital, author of Mama Doc Medicine: Finding Calm and Confidence in Parenting, Child Health, and Work-Life Balance

 

Fascinating! Think of all the controversial, hot-button topics that parents obsess about in a child’s first year—from vaccines and feeding, bed-sharing to sleep training. Weighing the scientific evidence, Callahan offers balanced insights and in-depth answers—a far cry from the oversimplified advice prescribed by many ‘parenting experts.’ The result: a must-have guide that’s substantive and extremely engaging. 

~Jena Pincott, author of Do Chocolate Lovers Have Sweeter Babies? The Surprising Science of Pregnancy

I’m so grateful to these thoughtful people, all authors themselves, for taking the time to read my manuscript and write short reviews.

I hope you’ll check out my book and let me know what you think!

 

What To Do About Babies and Peanuts: New Study Finds Early Exposure Can Prevent Allergy

You’ve probably already seen headlines about a study showing that feeding children small amounts of peanut products in the first 5 years of life can prevent the development of peanut allergy. The study was conducted in the U.K., led by Gideon Lack of King’s College London, and was published this week in the New England Journal of Medicine (free full text available here).1

Why is this study important?

Photo by Sanja Gjenero

Photo by Sanja Gjenero

Food allergies are on the rise in Western countries, and peanut allergy is one of the scariest. In the U.S., more than 2% of children and their families are now living with a peanut allergy, representing a 5-fold increase in prevalence since 1997.2,3 And this allergy isn’t just an inconvenience; it’s now the biggest cause of anaphylaxis and death related to food allergy in the U.S.4 This is a huge concern to parents wondering when and how to introduce peanuts to their kids, but the advice on this matter has been really confusing over the last 15 years.

In 2000, the AAP recommended delaying the introduction of peanut and other commonly allergenic foods (i.e., wheat, eggs, fish, cow’s milk) until at least the first birthday and until age 3 for kids thought to be high-risk for allergy.5 While this advice may have seemed reasonable, it was never based on good evidence – just a best guess based on knowledge at the time.

Meanwhile, the incidence of food allergies continued to climb, and epidemiological evidence emerged that avoiding allergens might backfire. In 2008, the AAP issued new guidelines stating that there was no evidence that delaying introduction of solid foods, including common allergens, beyond 4 to 6 months of age would protect children from developing allergies.6 This document was intentionally vague, because at the time, there weren’t any studies to give more specific guidance on when to introduce what, in what amounts, etc. And this flip-flop in advice, which was also mirrored in many other countries, has left a lot of parents confused.

Gideon Lack and colleagues published a study in 2008 that found that the incidence of peanut allergy among Jewish children in the U.K. was 10-fold higher compared with those growing up in Israel.7 Comparing the mean age of introduction of peanut protein between the two countries, they found that babies in Israel were commonly introduced to peanut in their first year, while babies in the U.K. were not. This led them to their hypothesis that early exposure to peanut might help prevent the development of peanut allergy, and that’s what the current study tested.

How was this study conducted?

The researchers recruited babies between the ages of 4 and 11 months that were high risk for developing peanut allergy because they had severe eczema, egg allergy, or both. Before entering the study, the babies were tested using a skin-prick test to see if they were already sensitive to peanut. If so, they were excluded from the study. Those who showed no sensitivity (530 babies) or only mild sensitivity (98 babies) were included in the study and randomized to two groups. In the “avoidance” group, parents were instructed not to feed their children peanut at all. In the “consumption” group, parents were asked to give their children 6 grams of peanut protein per week, spread across at least 3 meals. Both treatments were continued through age 5, when all of the children were tested for peanut allergy.

bambaWhat does 6 grams of peanut protein look like? It’s the amount in about 25 peanuts, or 3-4 tablespoons of peanut butter. In this study, parents in the consumption group were encouraged to feed a snack called Bamba, made of puffed corn and flavored with peanut butter. (Think Cheetos but with peanut butter instead of neon cheese powder.) Bamba was chosen because it was reported to be one of the main peanut sources for Israeli babies in the previously mentioned study. Kids who weren’t into Bamba were given smooth peanut butter instead.

What were the results of the study?

The study found a striking reduction in peanut allergy in the kids that ate peanut during the first 5 years of life. Among the kids without peanut sensitivity at the start of the study, 13.7% of those that avoided peanut had peanut allergy, whereas just 1.9% of those who had consumed peanut were allergic by age 5. That’s an 86% reduction in peanut allergy, and yes, that’s a HUGE result.

Among the kids that had a mild reaction to the baseline skin prick test, peanut allergy was more common, but again, the prevalence was reduced by peanut consumption early in life (10.6% in the consumption group vs. 35.3% in the avoidance group). Thus, the researchers concluded that exposing kids to small amounts of peanut protein early in life could both prevent peanut allergy and even treat those already mildly sensitized. Remember that all of the kids in this study were already high-risk for developing peanut allergy due to having eczema and/or an egg allergy. Normally, about 15-20% of this group would end up with a peanut allergy

We don’t yet know what will happen beyond 5 years of age, but the researchers are conducting a follow-up study in which the same children have been asked to completely avoid peanut for a year to see if this impacts their development of peanut allergy.

What does this mean for parents feeding children?

We should always be cautious about changing practices based on the results of just one study. However, this is is a really strong study showing dramatic results. Although we’ve known for a while that avoiding peanuts early in life doesn’t help, this is the first study to test peanut exposure in high-risk kids, and it showed that this can actually prevent allergy. I think it is a game changer.

Still, there is a lot we don’t know. We don’t know if there is an optimal window for introducing peanut or how much is really needed, and we don’t know if early peanut exposure could help infants that have already developed a real peanut allergy. We need more studies to help clarify these questions, but at least we’re asking the right questions now.

In a Scientific American interview (well worth reading in its entirety), the lead researcher for this study, Gideon Lack, gave his advice to parents wondering what to do about peanuts (Note that in the U.K., the term “weaning” means the introduction of solid foods, not stopping breast or bottle-feeding.):

“Among low-risk kids that account for 80 to 90 percent of population—those that don’t have eczema in the first six months to year of life and don’t have any evidence of food allergies—I would recommend that these children eat peanut protein or peanut in various forms, depending on the culture. Low-risk children should start eating peanut butter as soon as weaning is established. You don’t want peanuts to be the first food because if the kid is gagging or choking, it could represent allergic manifestation but it may also just indicate the child hasn’t developed the coordination to eat solid foods.

Higher-risk kids, those with any manifestation of eczema or food allergy, should see an appropriate health care provider, which could be an allergist or a pediatrician, and have skin prick testing done for peanut as soon as these high-risk symptoms develop. If the child tests negative, the child should be encouraged to eat peanut at home. If the skin test is a small positive, like it was for some of the kids in our study, then the children should have their first exposure or consumption of peanut under medical supervision; and if they tolerate it they should be encouraged to continue to have peanut regularly in their diet for at least the first three years of life. Based on the evidence we have, one could arguably say the first five years of life.”

I think this advice makes good sense. If you’re worried that your baby might be high-risk for peanut allergy, definitely talk to your child’s pediatrician to make a personalized plan for introduction. Keep in mind that you should always pay close attention whenever your baby tries a new food for the first time so that you can be alert to a reaction. Also take care to ensure you’re introducing peanut in a form that your child can handle, like smooth peanut butter or peanut sauces, avoiding whole peanuts until you’re confident that your child can chew them without choking. (Anyone want to place bets on how long it will be until we see a Bamba-like product marketed towards babies and young kids in the U.S.? I’m not aware of one currently.)

The big question in my mind is whether or not this same strategy of early exposure will apply to other common allergens. We already have some evidence for this. For example, one study found that children first exposed to wheat between 4 and 6 months (vs. after 6 months) had a 4-fold decreased risk of wheat allergy.8 Another found that children who first had cooked egg at 4 to 6 months had the lowest incidence of egg allergy, whereas those starting egg at 10-12 months had a 6-fold increased risk.9 Interestingly, this protective effect only worked with cooked egg (boiled, scrambled, fried, or poached), not with egg in baked goods. (Maybe baking denatures the egg protein more?) However, these were observational studies – not randomized – and confounding factors could have influenced allergy risk and early feeding practices. We need more randomized studies like the current peanut one to know if the early exposure strategy will work for other allergens and to figure out optimal timing and amounts of exposure.

The peanut study adds to a growing body of evidence that there may be a kind of sweet spot for introducing food proteins, including those that can trigger allergy – not too early and not too late. Studies show that introducing foods before 4 months can increase the risk of allergy, but waiting too long might also be problematic. Introducing babies to these foods at the right time seems to give their developing immune systems a chance to learn to tolerate the protein rather than attacking it.

As parents, it can be frustrating to see the “official” advice on introducing allergens flip-flop so dramatically in just 15 years. I’m sure there are parents out there who diligently followed the AAP’s advice from 2000, avoiding giving their children peanut, maybe even avoiding it themselves during pregnancy and breastfeeding, whose kids ended up with peanut allergies. Now we know how wrong that advice was, and that’s just maddening. But this is an area where the science has rapidly advanced in the last couple of decades, and the AAP and other health organizations have just been giving the best advice they can based on what we know. Finally, I think we are headed towards true evidence-based recommendations in this area. As a parent who will be introducing peanut to my baby in a few months, I think that’s something to celebrate.

What advice were you given about introducing peanuts to your baby? Will this study change the way you do it with a new baby?

References:

  1. Du Toit, G. et al. Randomized Trial of Peanut Consumption in Infants at Risk for Peanut Allergy. N. Engl. J. Med. 0, null (2015).
  2. Sicherer, S. H., Muñoz-Furlong, A., Godbold, J. H. & Sampson, H. A. US prevalence of self-reported peanut, tree nut, and sesame allergy: 11-year follow-up. J. Allergy Clin. Immunol. 125, 1322–1326 (2010).
  3. Bunyavanich, S. et al. Peanut allergy prevalence among school-age children in a US cohort not selected for any disease. J. Allergy Clin. Immunol. 134, 753–755 (2014).
  4. Sampson, H. A. Peanut Allergy. N. Engl. J. Med. 346, 1294–1299 (2002).
  5. Nutrition, C. on. Hypoallergenic Infant Formulas. Pediatrics 106, 346–349 (2000).
  6. Greer, F. R., Sicherer, S. H. & Burks, A. W. Effects of Early Nutritional Interventions on the Development of Atopic Disease in Infants and Children: The Role of Maternal Dietary Restriction, Breastfeeding, Timing of Introduction of Complementary Foods, and Hydrolyzed Formulas. Pediatrics 121, 183–191 (2008).
  7. Du Toit, G. et al. Early consumption of peanuts in infancy is associated with a low prevalence of peanut allergy. J. Allergy Clin. Immunol. 122, 984–991 (2008).
  8. Poole, J. A. et al. Timing of Initial Exposure to Cereal Grains and the Risk of Wheat Allergy. Pediatrics 117, 2175–2182 (2006).
  9. Koplin, J. J. et al. Can early introduction of egg prevent egg allergy in infants? A population-based study. J. Allergy Clin. Immunol. 126, 807–813 (2010).

Measles Is Serious (A History Lesson from My Grandmother)

Measles is back. The outbreak of this highly contagious viral illness that started at Disneyland in December has spread across the country and shows no signs of slowing. As of February 6, the CDC reported 121 cases in 17 states in this year alone, most linked to Disneyland. In 2014, we had 644 cases of measles in the U.S. This is a striking increase compared to the last 15 years, when we usually saw less than 100 cases in an entire year.

measles 2015 CDCI’m sorry that so many people have been sickened in this outbreak and hope that it is reined in soon. This is no easy task given our mobile society and the fact that we like to congregate in places like Disneyland, schools, doctors’ offices, hospitals, airplanes, and shopping malls. Add to that the pockets of unvaccinated people where measles can easily spread, and we have a recipe for still more outbreaks until we can improve vaccination rates. In this situation, I particularly feel for those who can’t be vaccinated. Babies under 12 months of age and people who are too immunocompromised to get the MMR vaccine, like cancer patients receiving chemotherapy, are counting on the rest of us to get vaccinated and reduce the spread of this disease. Right now, we’re letting them down.

One positive outcome to this outbreak is that it has sparked lots more conversation about vaccines. It inspired me to be more public about proudly stating that our family is fully vaccinated. And I wrote an op-ed piece for my local paper, the Register-Guard, about the risk of measles in our community, given the low vaccination rates in our schools.

FB profile pic(Our baby, of course, has so far only received the newborn Hepatitis B dose. He won’t receive the MMR shot, which includes the measles vaccine, until 12 months of age.)

I spent a lot of time researching vaccines last year for my book. The result is an in-depth look at vaccine development, risks and benefits, and safety testing and monitoring. I also cover some specific vaccine concerns, like whether or not we give too many too soon (we don’t) and if we should be worried about aluminum in vaccines (we shouldn’t). (I don’t just tell you these things, though; I break down the science for you.) I read hundreds of papers about childhood vaccines, talked with researchers, and felt more confident than ever about vaccinating my kids on the recommended schedule.

There was one other bit of vaccine research that may have been the most meaningful to me: I flew to Florida to interview my grandmother, now 90 years old. She raised seven children before most of today’s vaccines existed. She was a mother during the 1952 polio epidemic that killed 3,145 and paralyzed more than 21,000 in the U.S. She was having her babies before a vaccine for rubella was available. That disease caused 11,250 miscarriages, 2,100 stillbirths, and 20,000 children to be born with birth defects in a 1964-1965 outbreak in the U.S.

My grandmother also nursed her children through the measles. Before the vaccine, nearly every child suffered through a case of measles at some point in childhood. During the current measles outbreak, I’ve seen some comments downplaying the seriousness of this disease. After all, most kids did survive measles without long-term consequences. However, many didn’t. Among those who didn’t survive was my grandparent’s second child, Frankie. In 1956, at the age of 6, he died of encephalitis, or inflammation of the brain, a complication of measles.

My dad was the oldest of my grandparents’ children and the first of 3 boys: Richard, Frankie, and Larry. When the boys were little, the family lived in a faculty housing unit at Princeton, where my grandfather was an English professor. The families that shared the building were a tight-knit community. They built a playground together and parents took turns keeping an eye on the kids. “It was such a marvelous place to grow up,” my grandmother told me. “There were a whole bunch of kids, and you knew every single parent. Had conferences about your children and so on.”

Three brothers (from left to right): Richard, Frankie, and Larry Green, circa 1953 or 1954, in Princeton, New Jersey. Frankie died in 1956, at age 6, of encephalitis caused by measles. Photo by Margaret Green, used with permission.

Three brothers (from left to right): Richard, Frankie, and Larry Green, circa 1953 or 1954, in Princeton, New Jersey. Frankie died in 1956, at age 6, of encephalitis caused by measles. Photo by Margaret Green, used with permission.

In May of 1956, all three boys came down with measles. My grandmother remembers neighbors remarking that they were lucky to get it all at once, although this wasn’t surprising given that measles is one of the most contagious pathogens on earth. Those infected are contagious for several days before the characteristic rash appears, and the virus can survive in respiratory droplets, suspended in the air, for two days. Continue reading

Pertussis Vaccination in Every Pregnancy: Is it Safe and Effective?

I’m now 37 weeks pregnant, and it blows my mind how quickly this pregnancy has flown by. Now the days are ticking by faster than I can tick things off of my to-do list, and I can feel my body warming up for birth with increasing Braxton Hicks contractions and the baby dropping into my pelvis.

Preparing for a new baby means lots of things to me. There is the physical preparation of washing and folding tiny clothes and setting up baby’s space for changing and sleeping (in our bedroom for now). There is the arduous task of coming up with names – two of them, since we don’t know the baby’s sex. There is the mental preparation of imagining life with a new baby, trying to map out a few strategies for coping with wakeful nights and baby-filled days. There are the talks with Cee about how things will change and how they will stay the same, how she can help us with the baby, and how we’ll help her to adapt to the change in her life.

There’s also the very important aspect of making sure that we do everything we can to protect our new baby’s health, especially before the first round of immunizations at 2 months. This baby will be born during the season of flu and cold viruses, and this year is predicted to be a pretty bad one for the flu. Just south of our home in Oregon, California has so far recorded nearly 10,000 cases of pertussis, also known as whooping cough, this year, more than they’ve seen in 70 years. Cee will be exposed to a range of pathogens in preschool, and my husband will encounter them in his job in healthcare. We’ll do our best to protect our baby by leaving our shoes at the front door, changing clothes when needed, and washing our hands frequently. I also plan to breastfeed, which should confer some passive protection to the baby. However, some of the most important protection has hopefully already been given to this baby during pregnancy, because I’ve been vaccinated for both the flu (as soon as the vaccine was available this season, around 26 weeks) and pertussis around 34 weeks.

Getting vaccinated for flu and pertussis during pregnancy can protect your baby from these serious illnesses during early infancy.

Getting vaccinated for flu and pertussis during pregnancy can help protect your baby from these serious illnesses during early infancy.

The flu vaccine was first recommended for pregnant women in 1964,1 and there is a large body of research showing that the flu shot is safe in pregnancy and an effective way of preventing flu infections in expecting moms, which can pose a significant risk to the fetus. There’s also good evidence that influenza antibodies are transferred to the baby in utero,2 reducing baby’s chances of infection and hospitalization with the flu in early infancy.3,4 (Several of the above links direct you to evidence-based articles written by Tara Haelle on her blogs at Red Wine and Apple Sauce and Forbes. If you want to keep up with vaccine and other health news, Tara is an excellent blogger and science journalist to follow.)

The latest news on this year’s flu season is showing that most of the cases seen so far have been identified as being caused by seasonal influenza A H3N2, a nasty strain, and about half of these are a new subtype that isn’t well-covered by this year’s flu vaccine. If you haven’t yet gotten a flu shot this season, don’t let this news deter you. The flu vaccine will still protect you from the older strains of the flu and might decrease the severity of an infection with the newer type. The vaccine is very safe and still offers the best protection against the flu for you and your baby.

The recommendation that women be vaccinated against pertussis in every pregnancy – using the Tdap vaccine here in the U.S. – was new in 2012. It wasn’t recommended when I was pregnant with Cee in 2010, although I had recently gotten a Tdap booster for my job at the time. Several pregnant friends and readers have emailed me this fall asking if Tdap in pregnancy is safe and if they really need it, particularly if they were just vaccinated in the last couple of years. The good news is that there have been quite a few studies published on these questions in just the last year or two, and I’ll focus the rest of this post on the evidence for the Tdap shot in pregnancy.

What is the concern about pertussis in young infants?

We’ve seen big increases in pertussis recently, especially over the last decade. In 2012, there were more than 48,000 cases reported in the U.S., making it the worst year since 1955. Pertussis hits young infants the hardest. Among the 20 deaths from pertussis in the U.S. in 2012, 15 were in infants less than 3 months of age [PDF]. The first dose of pertussis vaccine is usually given with the DTaP shot at 2 months of age, and before this time, infants are particularly vulnerable to the disease. The 2012 recommendation that women be vaccinated with Tdap in the third trimester of every pregnancy came in response to these infant deaths, the hope being that maternal antibodies to pertussis could help protect infants during those first few months of life. Continue reading

Can Fetal Movements Predict a Baby’s Sex or Temperament?

I’m now 31 weeks pregnant. The weeks are flying by, and for the most part, I’m relishing all the physical changes in my body and the preparations for this baby. We waited a long time for this pregnancy, and it will probably be my last. I curl around my belly at night and think about the baby growing inside me. I wonder about the person that he or she will become and how our little family will adapt to welcome a second child. (We’ve chosen not to learn the sex of this baby until its birth.)

When I was pregnant with Cee and about to become a mom for the first time, I thought a lot about what kind of mother I would be and how this big life transition might alter my identity, my career path, my marriage, and my daily life. The baby-to-be was kind of a vague amalgamation of all the babies I’d known.

This time around, having been around many more babies, I recognize the individuals that babies are from the first days of life – and even in utero – and I spend a lot more time wondering about this baby’s temperament and personality. Introverted and contemplative, like Cee? Or totally different?

Filling me with wonder, this baby moves around in utero a lot, and this feels very different from my experience carrying Cee. I didn’t feel movement from Cee until around 23 weeks, but I began to feel this baby move at 16 weeks. And this baby continues to be very active, more than I remember with Cee, especially making big, dramatic movements in the evening hours but also having significant activity bouts throughout the day (and sometimes in the middle of the night, of course).

Because we don’t know the sex of this baby, I’m often asked if I have any predictions on that front. How would I know, I think? I don’t feel like I have any kind of gut instinct for this kind of thing, and I don’t buy into any of the old wives tails. But if I’m pushed to make a guess, I guess that this baby is a boy. And when I ask myself why that is, it comes down to this observation about more fetal movements. This baby feels different from Cee, and my brain makes a jump to sex as a possible explanation. And then I stop, remind myself that I’m perpetuating a total gender stereotype, and feel embarrassed.

One day, I repeated all of this to a friend as we walked together (complete with an apology for the gender stereotype), with Cee riding her bike within hearing distance. A couple of weeks later, my mom was talking to Cee on the phone and asked her if she thought the baby would be a boy or a girl. Cee answered in what seemed like a verbatim copy of my own explanation: “Well, Mom thinks that it’s a boy, because the baby moves around a lot inside of her, and I didn’t move very much.” Yikes. From now on, I’m keeping my mouth shut. And for the record, Cee is really hoping for a little sister.

All of this left me wondering if fetal movements can actually predict anything about the baby, whether sex or temperament, in postnatal life. I happened to be corresponding with Jena Pincott, author of Do Chocolate Lovers Have Sweeter Babies?, a few weeks ago, and I asked her if she knew of any research on this. She wrote back, “As for ‘in utero’ forecasts, my prediction is that your 2015 is going to be very, very busy!” and sent me a few research articles. I dug around and found quite a few more studies of this question. Finally, I could stop speculating and start talking science! Here’s what I found:

How is this question studied?

Most studies use ultrasound or a Doppler transducer placed on the mother’s belly to us baby profile croppedmeasure fetal movements. Most are conducted over a period of about an hour, during which the moms are asked to rest, and the best studies take several of these measurements over the course of the pregnancy. Studies of postnatal temperament then use standardized behavioral observations or questionnaires to describe aspects of the baby’s behavior.

Is it true that some fetuses are more active than others?

I wondered if my perception that I was carrying a more active fetus is this pregnancy was really true or if it was influenced by other factors? Continue reading

The Whole Truth About Infant Cereals: 7 Science-Based Tips

I recently received an email from a reader with a question about baby cereals:

“My wife and I are expecting a baby this October. We are planning to breastfeed but have lots of questions about introducing solid foods, particularly cereals. Do we have to feed the baby commercial baby cereals? I am concerned about all the extra crap that is put into commercial food, including unnecessary sugars and possible GMOs. Is there another product or whole food option that we could use to introduce grains to our baby instead of a commercial cereal product?”

~Brenda and Leah in San Diego, CA

Baby cereals have made a big swing in popularity over the last couple of generations. It wasn’t long ago that they were considered an essential first food, given to baby within the first months or even weeks of life. These days, in some circles, they’ve become a marker of lazy parenting, with conscientious parents choosing instead to prepare their own organic carrot purees or scrambling eggs with butter and breast milk. Cereals, meanwhile, get slammed in blog posts that call them over-processed, pointless, and even toxic. The movement towards more real foods for babies is definitely a good thing, but the scare-mongering about baby cereals is not. Brenda and Leah’s question is a great one, and it deserves an answer that is science-based, not sensationalized.

mother feeding her baby

1. You don’t have to feed a commercial baby cereal.

The reason infant cereals are typically recommended is that they are fortified with iron, and iron can become limiting during late infancy, particularly in breastfed babies. In early infancy, babies are mostly using stored iron that was transferred from mom during pregnancy, but by around 6 months, those stores run low, and they need to be getting some iron from solid foods. At this age, babies are growing and developing rapidly, and studies show that iron deficiency in infancy can cause developmental delays and lasting cognitive deficits.1–3 Breastfed babies are at greatest risk for iron deficiency,4,5 because breast milk is quite low in iron. (The iron in breast milk is efficiently absorbed, but there simply isn’t much of it.)

Commercial baby cereals are fortified with iron, effectively making it an easy way to deliver extra iron to lots of babies. In one study, among breastfed babies fed a fortified cereal daily, only 2.5% developed iron deficiency, compared with 14% of babies fed solids at their parents’ discretion.6 Infant formula is also fortified with iron, so babies that are formula-fed for at least half of their milk meals generally get enough iron that way.

However, there are other sources of iron that are actually better than fortified cereals. Meat, poultry, and fish all contain heme iron, which is more efficiently absorbed in the digestive tract than nonheme iron, the form found in plants like spinach and beans, as well as fortified cereals. Including a source of heme iron in a meal also increases the absorption of nonheme iron, so serving baby a little chicken with lentils actually increases the bioavailability of iron from the lentils. Baby cereals are often recommended as first foods, but this is based more on tradition and culture than on any scientific evidence. There is no reason why you can’t introduce those great heme sources of iron (meat, poultry, fish) as first foods, and in fact, this is now recommended by the AAP. If your baby is consuming 1-2 small servings of meat per day, plus other sources of non-heme iron, then there’s no reason that you have to supplement with an iron-fortified cereal. See more of my tips on ensuring that your baby gets enough iron in this post: 5 Practical Ways to Increase Iron in Your Baby’s Diet. Also, note that your pediatrician should test your baby for anemia around 12 months, so this will at least alert you if your baby is very deficient in iron.

Many babies and their parents also opt to skip spoon-feeding entirely, doing some version of Baby-Led Weaning. Cee simply wasn’t interested in being spoon-fed pureed foods, but she loved feeding herself soft finger foods. That meant that she ate very little infant cereal, except what I baked into muffins or pancakes (mostly to use up the box, but I figured she could also use the extra iron). This route can be fun and appropriate for babies that are ready to self-feed by around 6 months; others may need spoon-feeding and may love the interaction of feeding with a tuned-in caregiver.8 There are lots of options here, and the most important thing is to offer iron-rich foods (cereal or otherwise) and to follow your baby’s lead with texture and timing.

2. Commercial baby cereals may not be as bad as you think.

Here’s the Nutrition Facts label and ingredient list for Gerber’s oatmeal cereal (this one happens to be an organic product, but the conventional version is otherwise the same):

gerber oatmeal label

What’s in baby cereals? Take a look at the ingredient list. Continue reading

New Research on Gluten Introduction to Infants and Risk of Celiac Disease

If you’re worried about your child’s risk of celiac disease and wondering when to introduce gluten-containing foods, then you’ll want to know about two new studies published in the New England Journal of Medicine this week.

Gluten is delicious to most of us, but it can be devastating to those with celiac disease. Photo by Adrian van Leen

Gluten is delicious to most of us, but it can be devastating to those with celiac disease. Photo by Adrian van Leen

Celiac disease is an immune response to gluten, a protein found in wheat, barley, and rye. It causes inflammation and damage to the small intestine, and while it can be successfully managed with a gluten-free diet, it is a lifelong disease. (Celiac disease is distinct from non-celiac gluten sensitivity, which is a murky and controversial condition that may not be related to gluten at all.)

I reviewed the research on early infant feeding and risk of celiac disease on my blog about a year ago (Breastfeeding, Gluten Introduction, and Risk of Celiac Disease). I have since received lots of comments and messages from parents concerned about this, so I wanted to be sure to write about these important new studies.

These latest studies dramatically advance our understanding of this topic because they are randomized controlled trials. Both started with a group of babies already identified as being high-risk for celiac disease, randomly assigned them to different time of introduction of gluten, and then tracked their development of the disease. Previous studies were all observational, thus only able to identify associations between variables, and were limited by confounding factors and other sources of bias.

The first study was led by researchers in the Netherlands but included children born in 7 European countries and in Israel. 944 babies were identified as being high-risk for celiac based on a genetic predisposition (HLA genotype) and having a first-degree relative (parent or sibling) with celiac. The babies were randomized to two groups, and one group was given a small amount (100 mg) of gluten starting at 4 months of age, while the control group was given a placebo and instructed not to introduce gluten until 6 months, at which point parents in both groups were advised to gradually introduce gluten-containing foods. The incidence of celiac disease was tracked through 3 years of age, with all suspected cases confirmed with an intestinal biopsy. Overall, about 5% of the study participants developed celiac disease by age 3, and it made no difference whether gluten was introduced at 4 or 6 months. It also made no difference whether the babies were breastfed (exclusively or not) or currently breastfed at the time of gluten introduction.

The second study was conducted in Italy and had a similar design but instead compared gluten introduction at 6 vs. 12 months. Continue reading

Bed-sharing with Young Infants: Is It Safe After All?

Does bed-sharing with infants increase their risk of SIDS, even without known risk factors such as alcohol use, smoking, and co-sleeping on a couch or chair? A recent study makes what is probably the best attempt to date to answer this question. The study, led by U.K. researcher Peter Blair, was published last week in the journal PLOS ONE and is freely available to the public (yay!).1

mother and baby

How you bed share can make a big difference to safety. Co-sleeping on couches, alcohol use, and smoking are all very risky. The mom in the photo could keep her baby safer by removing the swaddle and ensuring that her baby sleeps on his back.

Many studies have found that co-sleeping is associated with an increased risk of SIDS, but most of this risk doesn’t come from co-sleeping per se, but rather doing so in particularly hazardous conditions, such as on a couch or with a parent who has been drinking. However, there’s an important, albeit controversial, caveat to this conclusion. Several studies have looked specifically at infants younger than 3 months and still found a significant risk of bed-sharing even in the absence of these other risk factors.2–6 The current study comes to conclusions much more reassuring to bed-sharing parents. In this study, bed-sharing without alcohol, smoking, or couch/chair co-sleeping was not associated with a significant SIDS risk in infants younger than 3 months and even seemed to be protective in older babies. Both of these findings run counter to previous studies and to the sleep recommendations of the AAP, so they deserve a close look.

How was the study conducted? Continue reading

Zero to Five: A Book Review and Giveaway

I received a review copy of a really cool book over the summer: Zero to Five: 70 Essential Parenting Tips Based on Science (and What I’ve Learned So Far) by Tracy Cutchlow. I loved the book and wanted to review it on my blog, and the publisher offered to give away 5 copies to Science of Mom readers! (If you’re curious about my policy on reviews and giveaways, check my About Me page.)

Author Tracy Cuthlow with her daughter, Geneva.

Author Tracy Cuthlow with her daughter, Geneva.

Zero to Five is a book of parenting advice starting with pregnancy and going up through age 5. Author Tracy Cutchlow is a former journalist at the Seattle Times and edited John Medina’s books Brain Rules and Brain Rules for Baby. Then she had a daughter, now 2, and was inspired to create a book that would bring together relevant, evidence-based parenting advice into an enjoyable and accessible format. I’d say she succeeded.

Each of the 70 parenting tips are explained in 2-4 page spreads summarizing the research in the area and accompanied by gorgeous candid photographs of children and parents. The tips are practical, and they’re explained simply, but they’re rooted in science.

ZTF-guard-babys-sleep

The book is divided into 9 topics headings, listed below with examples of some of my favorite tips in parentheses:

  • Prepare (Bolster your friendships; Expect conflict as a couple)
  • Love (Create a feeling of safety; Comfort newborn with the familiar)
  • Talk (Talk to your baby a ton; Read together; Teach sign language)
  • Sleep, eat, and potty (Guard your sleep; Guard baby’s sleep, too; Let baby decide how much to eat)
  • Play (Let baby touch that; Save the box; Make music with baby)
  • Connect (Choose empathy first; Allow mistakes, discomfort, boredom)
  • Discipline (Be firm but warm; Label intense emotions; Teach instead of punish)
  • Move (Rock, jiggle, and swing; Keep moving)
  • Slow down (Be still; Don’t bother to compare)

Some of these tips are obvious, like talking to your baby. But they’re also really important, and that’s one of the things I love about this book. Continue reading

What’s so important – and stressful – about family dinner?

A recent study about the stress of getting family meals on the table has been getting lots of attention from both the media and moms. A Slate piece, “Let’s Stop Idealizing the Home-Cooked Family Dinner,” posted Wednesday, has already garnered 3.5K comments on the article itself and more than 26K Facebook shares. This has obviously struck a nerve. While feeding a family is a big and often stressful job, some perspective about why we do it and what matters most about family meals might be helpful to families feeling the mealtime crunch.

The study itself, titled “The Joy of Cooking?”, was published in Contexts, a publication of the American Sociological Association geared to be accessible to the general public. The paper itself is a really interesting read and freely available online.

Researchers in the sociology and anthropology departments at North Carolina State University conducted the study. This was a qualitative study, which means that the data came in the form of stories, generated from interviews with real people. From the paper:

“Over the past year and a half, our research team conducted in-depth interviews with 150 black, white, and Latina mothers from all walks of life. We also spent over 250 hours conducting ethnographic observations with 12 working-class and poor families. We observed them in their homes as they prepared and ate meals, and tagged along on trips to the grocery store and to their children’s check-ups. Sitting around the kitchen table and getting a feel for these women’s lives, we came to appreciate the complexities involved in feeding a family.”

These kinds of methods are common in sociology and anthropology research, and they allow researchers to understand the many complex variables that contribute to how people feel and why they feel that way. However, we have to be careful about interpreting these studies beyond the individual stories that they provide. For example, this study wasn’t a random sample of moms, and it can’t give us quantitative information like the percentage of moms who find cooking to be an unbearable chore versus rewarding or enjoyable. It doesn’t allow us to look at correlations between family income and nights of home-cooked meals per week, for example.

Here’s what it can tell us: Continue reading