Saturday, July 21, 2012

The Trouble with Calma and the Quest for the Perfect Bottle Nipple

When breastfeeding moms either want or need for their baby to have expressed milk from a bottle, the question they usually ask is, “What bottle/nipple is most like the breast? Which bottle/nipple is best for breastfeeding babies?”

The simple truth is that the correct answer is, “None.” There is no nipple that is like the human breast. Some may be better or worse for a baby who is going back and forth between breast and bottle, but there is no “best." What matters much more in avoiding baby developing a bottle preference is how the baby’s caregiver feeds baby with the bottle.

The problem with marketing nipples as "most like breastfeeding," or with similar claims is that it undermines breastfeeding. This is why part of the purpose of the WHO CODE (World Health Organization's International Code of the Marketing of Breastmilk Substitutes) is to prevent the aggressing marketing of bottle nipples. 

One of the first bottle nipples to be marketed as “most like mother’s nipple” is the Nuk. Their claim, “Orthodontic design shaped like a mother's nipple during breastfeeding." The marketing claims are pretty convincing:

The NUK® Orthodontic bottle makes baby's transition from breast to bottle and back a seamless one. Every nipple has unique features to make it easier to move back and forth from breast to bottle. These bottles have been scientifically designed to make feeding easier.

I was working with a mom who was wanting to transition her baby off of bottles of expressed milk on to the breast. I asked her what nipples she was using and she told me Nuk. I mentioned that she may want to switch to a different bottle and nipple that would encourage baby to use his mouth more like he would on the breast. I explained to her that the Nuk nipples tended to encourage sucking that could interfere with breastfeeding. She was shocked. “But is says right on the package that it is most like mother’s nipple and good for breastfeeding babies!”. She fell for the marketing hook, line and sinker.

Independent research, summarized on,  has shown the problems with these “orthodontic” nipples:
  • Ultrasound studies by Smith revealed that round nipples with a broad base, as opposed to the "orthodontic nipples" with flattened tips, best facilitate tongue and jaw motions similar to sucking at the breast(1)
  • Although orthodontic nipples such as the Gerber Nuk are frequently recommended for use by nursing mothers, they seem to teach the baby to retract his tongue and hump it up in the back of his mouth during feeding.
  • This creates problems with breastfeeding, since babies must flatten their tongues and extend them forward to get milk from the breast. In addition to reducing milk transfer, this type of tongue movement can cause severely abraded nipples.(1), (2)

Newer nipples are getting much more sophisticated and have even bigger claims. The Breastflow bottle, by The First Years claims:

Works like mom

The only bottle with a 2-in-1 nipple that lets your baby use the same natural motions as breastfeeding.

Soft outer nipple

mimics the feel of the breast and allows baby's tongue to stay in the same position as breastfeeding.

Inner nipple

allows your baby to control the flow naturally like breastfeeding whether you use breast milk or formula.

While I can’t find any independent research on how much these are or are not “just like” the breast, the fact is it is impossible. Moms report trying these to avoid “nipple confusion” but the fact remains that anything other than moms breast has the potential to cause nipple confusion or bottle preference, particularly if baby is being overfed with them. There are no shortage of complaints about this somewhat complicated system with multiple parts being difficult to clean, or the nipple frequently leaking, or collapsing while baby is feeding. This is a lot of extra effort and work for moms who believe the marketing that this nipple is somehow best for their breastfed baby.

The mimijumi bottle is designed to look like the breast:

With natural colors, textures and forms, the mimijumi baby bottle provides the perfect complement to breastfeeding and the best possible transition to bottle feeding.

The innovative nipple design replicates a mother’s breast, creating a natural feeding and latching experience for a happier and healthier bottle fed baby. Bold colors and soft textures are combined to give the Not So Hungry bottle a distinctive, eye-catching appearance.

I want moms to understand that “the best possible transition to bottlefeeding” is a marketing ploy! They want you to buy their bottle. Even if they tried to make it most like the breast with the best of intentions, that does not make it so.

Looks don't make a difference when you are wanting to avoid a flow preference with your baby and make an easy transition from breast to bottle and back. Users of the mimijumi have reported a fast flow rate and a stiff nipple:

"I ordered this bottle thinking that it would be closest to a breast, but I was very mistaken. My husband filled the bottle with breast milk and turned the bottle upside-down over the sink to show me that the milk just comes streaming out of the nipple. The baby was practically choking when he fed her using this bottle."
"Not only is the nipple extremely hard and inflexible, it also lacks control over the flow rate. My baby was permanently choking with this bottle, even with the "slow flow" nipple." 
The new kid on the block comes with great marketing claims. Produced by the heavily marketed Medela brand comes the Calma:

Introducing Calma: Designed exclusively for breastmilk feeding.

Switching from bottle back to breast has never been easier. Calma was developed using evidence-based research on babies' natural feeding behavior so you can enjoy your breastfeeding bond longer.

With Calma, the milk will only flow if your baby works and creates vacuum to remove the milk. This enables the feeding behavior learned at the breast to be used with Calma.

I decided to do some more research after the comment from a breastfeeding mom on an on-line forum. Other moms on the breastfeeding forum were suggesting that her baby was being overfed with the bottle, and this was the underlying cause of the problems she was having. The amounts her baby was getting from the bottle exceeded what research suggests a breastfed baby should get. She responded that it was not possible that her baby was being overfed with the bottle because she was using the Calma, which is just like the breast. She would not even begin to listen to the possibility that baby was getting too much milk because she did not think it was possible with this specially designed nipple.

The truth is it is easy to overfeed with any bottle and just like the other contenders, the Calma does not replicate the human breast and deliver milk in the same way. It was not too hard to find the following information, right on the Medela website:

INTERVIEW: Conquering Breastfeeding Challenges with Calma (As if a bottle can solve breastfeeding problems, sigh.)

On the comments of this article on the Medela website several IBCLCs reported a consistent problem with fast flow, and babies choking on the surge of milk flowing into their mouths. A Medela representative responds to these complaints by explaining that a baby cannot suck on the Calma nipple the same way they do at the breast because it will cause too fast of a flow.

Wait a minute. Let’s all stop here right now. Didn’t Medela claim that this new wonder nipple, “enables the feeding behavior learned at the breast to be used with Calma.” Now they are saying baby needs to suck differently on the Calma than they do at the breast? The Medela rep further explains:

"We’ve found sometimes that Calma takes a little getting used to. Typically, babies suck vigorously at the beginning of a feeding to stimulate let down. With Calma, relaxed sucking, similar to the middle of a feeding, works best. Many moms found that after a few tries, babies adjust their sucking at the beginning of the feed with Calma and that Calma helped immensely with the transition from bottle to breast."

An IBCLC, who was complaining about the fast flow she had seen with the bottle poiints out:

"If babies have to adjust their suck to be LESS vigorous to adapt to a bottle, then they will not be sucking in an appropriate manner for the breast. Effectively you are admitting to what I have found with 100% of the clients I have seen who have tried this bottle — babies suck worse on the breast. So while you may have found some resilient babies who are highly adaptable (because most babies WILL eventually take the breast when mothers maintain their supply through pumping) the babies who are having significant problems that comprise my clientele will not. Furthermore, aspiration from choking is a health risk. The degree of choking I observed among my clients was severe — not mild — and much worse than with other bottles."

What really matters when choosing and using a bottle with a breastfed baby?

One of the main reasons a baby may prefer the bottle to the breast is due to flow preference. Baby likes the fast and immediate flow from the bottle. They come back to the breast and don’t want to “work” for the let down. Medela has basically just said that babies need to learn to not suck to trigger let down when using this bottle.

What do breastfeeding moms need to know about bottle feeding expressed milk?

Suggested Bottle Nipples

A few bottle nipples which have been tested and rated by lactation consultants come out at the top when it comes to a good slow flow rate and a shape that baby may be able to take with a wide latch like the breast. Always buy the slowest flow nipple:

Evenflo Classic: Pros: You can purchase glass or plastic bottles. No disposable liners, no extra pieces to clean, very inexpensive. Cons: slightly higher flow rate than the other 3 listed here, but still slow.

Playtex VentAire (standard, not wide) Pros: Middle price range, easy to find and purchase. Cons: Angled bottle is less than ideal as you want to hold the bottle horizontal to pace baby's bottle feeding. Extra parts to wash as the bottom needs to be taken apart to wash.

Dr. Brown's Standard Bottles Preemie Flow (or Level One Flow would be next best): Pros: No disposable liners needed. Available in both plastic and glass. Cons: several extra parts to clean including a vent inserts and straw-like vent reservoirs.

Playtex NaturaLatch: Pros: Easy to clean with no extra parts. Cons: need to purchase disposable linters for the bottles. Some babies will only latch onto the end of the nipple and use it like a straw.


(1) Smith, W., Erenbert, A., Nowak, A. Imaging evaluation of the human nipple during breast-feeding. Am J Dis Child 1988; 142:76-78.
(2) Nowak, A., Smith, W., Erenberg, A. Imaging evaluation of artificial nipples during bottle feeding. Arch Pediatr Adolesc Med 1994 Jan; 148:40-2.

© Teglene Ryan