Studies of Note: Type 1 Diabetes & Atopic Dermatitis

Two interesting studies came out in the past few weeks, neither of which got much publicity, and were reported with tremendous caution in the fear of sounding “anti-breastfeeding”. However, considering atopic dermatitis(AD)  and Type 1 diabetes are two of the most feared “risks” of formula feeding, I think these studies deserve a little attention. True, the AD one was funded by a formula company (Danone Research) , but it’s a fascinating study all the same, and the authors were uber-conscious of the bias inherent in their funding, and reported their findings accordingly. And as I’ve stated on the blog numerous times before, I really don’t see all that much difference in bias between a study funded by formula companies, and one that is conducted, analyzed and reported by a renowned breastfeeding advocate. Both of these circumstances require a bit of skepticism and hyper-analyzing on the part of the consumer, but for some reason, the latter scenario is seldom seen as anything but altruistic.

Anyway, on to the studies at hand. The first, Dietary Intervention in Infancy and Later Signs of Beta-Cell Autoimmunity, appears in the prestigious New England Journal of Medicine. Beta-cell autoimmunity is associated with Type 1 diabetes in genetically-susceptible individuals; the theory is that exposure to complex proteins in infancy heightens risk of beta-cell autoimmunity. So, the researchers wanted to see if using a casiein hydrolysate formula (the kind us parents with milk-or-soy-protein-intolerant kids are so fond of) rather than a regular, cows-milk based formula, would prevent this beta-cell autoimmunity from occurring.

Interestingly, at least from the free abstract (money’s tight, y’all, so you’ll have to excuse my inferior research here), it sounds as if this study used primarily breastfed kids whose mothers sometimes supplemented. I’m not sure what the dosage situation was – if these were occasional bottles or an everyday thing; if they included exclusively formula fed babies as well, etc. But the important part remains the same – there was a statistically significant difference (although the difference was relatively small, as they tend to be in most of these infant feeding studies) in outcome between the regular formula kids and the hydrolyzed group when it came to developing the autoantibodies which are associated with Type 1 diabetes, favoring the casien hydrolysate formula. (There was no significant difference in the number of actual cases of type 1 diabetes, however, between the control and test group). So if you are someone with a family history of Type 1 diabetes, it may be worth it to consider a formula like Alimentum or Nutramigen, or at least talk to your doctor about the pros and cons of these types of formula. I’m a believer in them for totally unscientific reasons – they gave me my son, and saved his gut, and I will be eternally grateful for that, so I will gladly admit a ginormous positive bias towards any study showing them in good favor.

Next up, the study funded by European formula company Danone, published in the Journal of Allergy and Clinical Immunology (the link will bring you to the full text of the study, if you’re interested). This one is pretty cool, too. Atopic dermatitis (an itchy, uncomfortable skin condition, the prevalence of which is rising in Western nations) is related to allergies in some cases, but those are mostly in kids with a family history of AD. The majority of cases are in babies with no family history of the condition, so these researchers focuses on a group with low-risk of AD for more useful results from a public health perspective. They hypothesized that using a prebiotic-enhanced formula would help reduce the risk of AD:

Because there is a broad consensus that the intestinal microbiota plays an important physiological role in the postnatal development of the immune system, many attempts have been made to influence the intestinal microbiota and herewith the occurrence of atopic manifestations by dietary interventions. A heavily marketed strategy for primary prevention is dietary supplementation of potentially beneficial bacteria (probiotics) as a tool to redirect the immune system away from atopy.

They took a group of 1130 infants from various European cities/medical centers with a low risk of AD. Some were exclusively breastfed; those who were not were randomly assigned to receive either a normal formula or one supplemented with prebiotics. The results were actually kind of dramatic, as these things go.
They found that using a prebiotic-enriched formula “reduces the incidence of AD up to the first birthday in infants at low risk for atopy by 44% compared with the control group and down to a level similar to that of fully breast-fed infants. The severity of AD, however, was not affected significantly.”

So, the next time you hear that formula research isn’t worthwhile, you’ll have two studies to bolster your side of the debate. This isn’t a question of breast vs bottle; it’s about making bottle feeding the best it can possibly be for those who cannot or chose not to breastfeed. We have a right to know that prebiotics might be useful in protecting against AD, or that a baby at risk of Type 1 diabetes might fare better on a hydrolysate formula – as much right as we have to know that breastfeeding has a correlation with less incidence of gastrointestinal problems, or that receiving a formula freebie bag is associated with a shorter duration of exclusive breastfeeding…. don’t we?

Hyping hydrolysates: All about hypoallergenic formulas

I want to admit my bias towards hydolysates up front:  I think they are magical. My son has been on hypoallergenic formula since he was about 3 months old, and the difference between FC on breastmilk/regular formula/soy formula and the hypoallergenic formula we ultimately switched him to was astounding. It was like the kid had received a spontaneous lobotomy. He was miserable for the first 10 weeks of his life, with terrible skin rashes, gas, stomach issues, and a personality that can best be described as the Grinch meets Chairman Mao; within 24 hours of switching him to hypoallergenic formula, he could have starred as the “after”  in a Harvey Karp instructional video. FC was truly the happiest baby on the block, thanks to Alimentum.

Still, I was concerned about the long-term safety of such a space-age, highly processed formula. The stuff smelled like regurgitated potatoes. (Although for some reason, FC loved it; up until a month ago, we still used a scoop of the stuff to flavor his hemp milk because he so adores the taste. But then again, he likes kiwi as well, and hates chocolate. I’m blaming FH’s taste genes.) And the whole “pre-digested” thing kind of skeeved me out. So, I did a little research, and the following is what I’ve found. Needless to say, I am by no means a doctor or have any background in science; this is just what I’ve gleaned from a layman’s perspective (with the slight advantage of a journalism background that focused on health issues), so take it all with a grain of salt. Or a grain of pre-digested protein. Your choice.

First, a definition: What are hydrolysates?

Basically, in kids who are allergic or sensitive to milk protein, the lower the molecular weight of a protein, the better. Casein hydrolysates like Similac Alimentum or Enfamil Nutramigen contain tiny, broken-down versions of milk protein, making it easier for milk-sensitive babies to digest. There’s another level of hypoallergenic-ness (yes, I made up that word, sue me) which you find in amino-acid based formula (Neocate); for some babies, even the infinitesimal amount of milk product in the hydrolysates is problematic. Since Neocate is only available by prescription, and the majority of kids with food sensitivities have success with the over-the-counter hydrolysates, we’re going to focus on these.


What are the nutritional differences?

Comparing nutritional labels, there doesn’t seem to be much difference between your average milk-based formula and a casein hydrolysate one. But a 2003 study in the American Journal of Clinical Nutrition did find that “the iron status of infants fed (casein hydrolysate formula) was lower than that of all other groups. The amounts of amino acids provided by hydrolysate formulas appear excessive compared with regular formula, which is reflected by high serum urea nitrogen… and high plasma amino acid concentrations.” The study authors suggest, in their conclusion, that a “reduced and more balanced amino acid content of hydrolysate formulas may be beneficial.” I’m not sure if the formula companies have changed the recipe since 2003, but I will look into it and get back to you.

The International Society of Infant Food Manufacturers has a good run down of the nutritional issues surrounding hydrolysates, but I’m well aware that there’s a bias against the formula organizations, so do with this what you will. They claim that “on the whole, available data suggest that there is no evidence that feeding (hydrolysate formula) impairs the growth and biochemical parameters of term infants. There is also no evidence of differences between infants fed (hydrolysates) and an adapted cow’s milk formula and/or human milk on growth parameters and biochemical parameters, except on indices of protein metabolism.”

What’s the deal on allergies?

A 2008 clinical report from the AAP suggested that hydrolysates may actually have a preventative effect against allergies:

The documented benefits of nutritional intervention that may prevent or delay the onset of atopic disease are largely limited to infants at high risk of developing allergy (ie, infants with at least 1 first-degree relative [parent or sibling] with allergic disease). Current evidence does not support a major role for maternal dietary restrictions during pregnancy or lactation. There is evidence that breastfeeding for at least 4 months, compared with feeding formula made with intact cow milk protein, prevents or delays the occurrence of atopic dermatitis, cow milk allergy, and wheezing in early childhood. In studies of infants at high risk of atopy and who are not exclusively breastfed for 4 to 6 months, there is modest evidence that the onset of atopic disease may be delayed or prevented by the use of hydrolyzed formulas compared with formula made with intact cow milk protein, particularly for atopic dermatitis.

It’s not clear in this synopsis, but reading through the entire study, it seems that both breastfeeding and use of hydrolysate formulas confer equal benefits in this particular case. Obviously, if you have a history of allergies and are able to breastfeed, it’s a no-brainer – why feed your kid expensive and atrociously smelly formula? But for those of us whose kids are unable to tolerate breastmilk due to severe allergies, or who cannot breastfeed for any other reason, but have a family history of allergies, the hydrolysates might be worth the cash.

The skinny on soy: Are soy formulas safe?

Let me preface this post by saying that I am a huge fan of the soybean. Having been a vegetarian (and occasional vegan) for the past 20 years, soy products and I have obviously become BFF.

So when we were trying to figure out my son’s eating issues, I was hoping that soy formula would be the golden ticket. Unfortunately, it turned out that he was allergic to both dairy and soy, and we ended up on hypollergenic formula (Similac Alimemtum). But this had nothing to do with my feelings about soy. Just so we are clear. I still love you, my sweet soybean!

Soy has been in the news a lot lately. Once the golden child of women’s health (it was said to prevent numerous cancers, heart disease, and help alleviate problems associated with menopause), like so many things that have once been exalted for health reasons, the establishment has turned on poor old soy. Now it is being blamed for all sorts of ills, including decreasing metabolism, enlarging thyroids, and killing testicular cells. Yummy.

What does this mean for babies on soy formula? One would think that any problems associated with soy would be exacerbated in its use as an infant formula, since, well, babies are small, and things affect them more strongly than bigger humans (how’s that for a scientific explanation?). In 2008, The AAP came out with a report called “Use of Soy Protein-Based Formulas in Infant Feeding,” which updated it’s 1998 review of soy formulas. Basically, it says the following:

1. Soy formulas have no advantage over cow milk-based formulas.

2. For pre-term infants, soy formulas are not recommended.

3. Soybeans are high in phytoestrogens (estrogen-like compounds found in plant products), but there is no “conclusive evidence” from any study showing that that “eating soy causes problems to human development, reproduction or endocrine function.” (WebMD)

3. If you are vegetarian and do not feel comfortable with milk products (well, actually, the correct term would be “vegan” as vegetarians are fine with dairy products, but hey, semantics…it’s not like the AAP has dieticians on staff or anything….) or your child is lactose intolerant, soy is a safe choice; otherwise stick to milk-based formulas.

4. For kids with food allergies, hypoallergenic formulas are a better bet; many kids who are sensitive to cow’s milk protein are also sensitive to soy. There is no evidence that soy formula confers any protection against the development of allergies over regular formula. (Note: there actually was a recent AAP paper stating that there is possibly an advantage to hydrolysate formulas like Alimentum in this respect; that’s fodder for another post though, so we won’t go into it here.)
 

Now that we’ve seen what the AAP has to say, let’s look at this from a real-world perspective. Telling a parent that there are “no conclusive studies” on something and then warning him/her to stay away from it isn’t very comforting to that parent. No one wants to be responsible for his/her kid growing breasts at age 8 (especially if that kid is a boy). Why would they warn parents away from soy formula if it were safe?

Here’s one possible answer: the AAP likes to cover it’s bases. These are the same folks who told us to treat peanuts as arsenic for the first few years of a kid’s life; now they are sheepishly (and quietly) admitting that perhaps this policy had a contradictory effect (more kids getting peanut allergies rather than less). Take their statements with a grain of salt – like your mom, they mean well, but can be a little over-dramatic. The truth is that there have simply not been enough studies on the long-term effects of soy formula. I know this won’t put anyone’s mind at ease, but let’s look at it another way – science is discovering new advantages and disadvantages to everything in our world every freaking day. Soy formula has been used for the past 100 years, and while there could obviously be a study that comes out tomorrow saying that it causes all sorts of evils, there could just as easily be a study that proves that potatoes cause cancer. You just never know. All you can do is make an informed decision and weight the pros and cons, and overall, soy formula seems to be a relatively safe choice.

I turned to Dr. Greene, my new favorite pop pediatrician, for some insight. In 2001, he posted the following:

Babies who drink soy formula receive significant amounts of estrogen-like compounds (phytoestrogens) in the form of soy isoflavones. This happens at a developmental time when permanent effects are theoretically possible. Some have speculated that soy formula might be responsible for early puberty in girls or infertility in boys.  The August 15, 2001 issue of The Journal of the American Medical Association (JAMA) contains the results of a study of 811 adults, some of who drank soy formula as children and others who drank milk-based formulas. No statistically significant differences were observed between the groups in either women or men. They followed more than 30 different measures of general health or reproductive health. Breast milk is clearly the ideal food for babies, but this study is quite reassuring that soy formulas are a safe alternative. This is good news for babies who do not tolerate cow’s milk formulas well.

Granted, this was nine years ago; the AAP statement came out seven years later. But reading the AAP statement, it doesn’t seem like much has changed, does it?

What I think has changed is the perception of soy in general. The issue with soy is that it is in practically everything. Read any label in your kitchen cupboard – I guarantee you’ll see some terms like soy protein isolate, soy lecithin, soy isoflavens. Even if nary a cube of tofu should ever pass your lips, you’ll still be consuming a fair amount of soy in your lifetime. The problems we are seeing now that are associated with soy are most likely from an overabundance of it in our diets – a real conundrum for vegetarians like me. Once I started looking into it, I realized I was eating soy cheese, soy yogurt, soy milk, tofu, and a myriad of veggie-friendly products all made from soy. Rather than freaking out completely, I opted to switch to almond milk, coconut milk yogurt, and decided to eat dairy cheese or no cheese at all. I still eat tofu and veggie meat (made with soy) nearly every day, but at least it’s not the main ingedient in everything I eat. Moderation, people, moderation.

Back to the babies… If your child can’t tolerate dairy, you basically have two choices in formula – soy or hypoallergenic. It comes down to preference – for those who don’t like the idea of processed, chemical food, then soy formula will probably be a better bet. You can get it in organic variants, and at least you can prononce the majority of the ingredients. The hydrolysate formulas tend to fare better in studies, but they are completely manufactured, not available organic, and extremely cost prohibitive. Plus, a lot of kids won’t drink them, because they taste like crap. Weight the pros and cons and realize that no matter what, you’ll be able to switch them off the stuff in a few short months. (At which point, if you are concerned about an overabundance of soy, I would recommend weaning to regular milk, or a substitute other than soy, like rice, oat or hemp).

Take away message? Go for the soy if it works for your family – my hubbie was raised on the stuff and he doesn’t have boobs. I promise.

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