One of the most powerful choices parents make before their baby delivers is how to feed her or him.
The source of nutrition for newborns and young infants is always liquid, and essentially limited to two options- breast milk or formula.
Recent findings are very reassuring to parents as they weigh their options, and find a path that allows them to be as close and comfortable with their newborn as possible.
What the Newborn Needs
Birth interrupts the complete nutritional and metabolic support system of the placenta and uterus, which provide the developing baby with everything they need from oxygen to food to all necessary compounds. Once born, the baby becomes like us, requiring air, food and water. Air of course is available to all with no effort, but water and food must always come from somewhere.
Breast milk is the food that has evolved to provide just the right amount of all the nutrients, protein, carbohydrate, fat, and water that the newborn and young infant need. How much your baby needs is, like oxygen, determined solely by your baby. Occasionally there are times when the production of breast milk by the mother’s body does not yield the standard amount of nutrient, but in the vast majority of experiences, the breast milk produced offers about 20 calories per ounce and also a standard amount of all the nutrients.
Throughout history, there have been newborns and infants who could not breastfeed, for all sorts of reasons. But substitutes that could provide a similar quality of support were hard to find. In pre-modern times, the solution often included having a relative or substitute nurse, the practice referred to as wet nursing.
By the early 20th century, modern chemistry techniques were able to describe the nature of breast milk and its nutritional compositions in greater detail. This led to the development of a liquid called infant formula. The first modern infant formulas were sold in the 1920’s, but their current composition in all but minor details came into use by the 1950’s.
The liquids are called formula because there is only one formula that can be sold to feed babies. That formula describes a very uniform set of concentrations of all the key nutrients, such as the 20 calorie per ounce setting for energy concentration. But a constant formula for concentrations of all fats, proteins, carbohydrates, vitamins and minerals is present as well. By design all these concentrations are aimed at replicating those found in breast milk.
From time to time formula companies feel the need to add a very tiny amount of something, to make a distinction. Many years ago it was the amino acid taurine. Currently many formulas feature the omega-3 fatty acid DHA and similar additives. The point is that a formula cannot have too much added or all the concentrations of all the other nutrients will be thrown off.
There are two key points that flow from these facts on formulas:
- All the standard infant formulas sold in the US are essentially identical. All parents using infant formulas should feel entirely free to switch brands at will.
- Any standard infant formula is a remarkable accomplishment, providing a very effective alternative to breast milk when needed. The formulation is so close to breast milk that infant formula works well, more on that below.
The Evidence for a Difference with Breast Milk
The question of whether breast milk offers benefits beyond formula must start with the observation that only breast milk actually evolved to feed newborns and infants. All other foods we eat were either discovered (fruits, vegetables, meats) or invented as food sources by us. In that sense formula is no different than all other foods, it was not evolved, it was chosen or formed. From that stance, breast milk will always remain the standard to which all other choices must compare.
As to the relative value of breast milk v. formula, the question has raged ever since formula was first developed. There have been times since that breast milk was thought of as the clearly superior choice, and times when formula was thought to be the clearly superior choice. And the reasons for preference have varied dramatically over time. Some preferences have been based on the aesthetics of feeding, with some people and some places finding one or the other very appealing and the other very upsetting.
Some preferences have been based on health concerns. Advocates of formula when formula was preferred, argued that a sterile formula feed was much cleaner. More recently, advocates of breast feeding have argued that being fed breast milk yields a wide array of health advantages including less risk of asthma, allergy, obesity later in life, cavities, and ADHD.
Perhaps the most closely watched question is whether breast feeding has an impact on cognitive function.
Some years ago, the American Academy of Pediatrics (AAP) issued guidelines based on finding that across a very broad range of health indicators, including cognition, asthma, allergy, obesity, and many other items that breast fed infants emerged better off than formula fed infants. These findings led the guidelines to recommend exclusive breast feeding for the first 6 months of life (later the AAP amended this to advocate for starting solids by 4-6 months of life), and continued breast feeding for a total of 12 months.
The Difference Between Rich and Poor Countries on this Question
Before looking at the recent reports on the difference between babies fed by formula and breast milk, this important distinction must be made clear. Formula in most of the world comes with a devastating disadvantage- the nearly complete absence of safe water and the depth of poverty. Two items are absolutely necessary to use infant formula- money and clean water. Whether purchased as powder or in sterile pre-mixed cans, it takes money to use formula. At least 1 billion people in the world simply cannot afford to provide all the formula a newborn and infant will need.
The lack of clean water is devastating to the use of formula for a billion and likely more. Dirty water in the use of formula is a direct attack on the basic health of any newborn and infant.
Finally, the global fact of deep and enduring malnutrition creates billions of newborns and infants who are categorically far more vulnerable to common infections, so even if breast feeding reduces infection rates to a mild extent, that difference can save large numbers of lives in poor countries.
Putting it all together, outcomes in poor countries where money is scarce and clean water absent, where malnutrition is rampant and makes common childhood viruses deadly make clear that breast feeding is vastly superior, and in fact, an imperative for newborns and infants.
The Recent Data on the Impact of Breast Feeding in the United States
In the United States money, water, and malnutrition really do not have an impact on the question of how infants do on breast milk versus formula.
With regard to money, few families cannot find access to formula if they choose to use it. For families too poor to buy formula, the WIC program makes formula available at no charge.
With regard to water, clean water is available across the United States, there are few reports of diseases following use of public water supplies.
With regard to malnutrition, the actual rates of severely poor outcomes following colds and stomach flus in the US are very low, these illnesses are radically safer to experience in the US than in the poor countries of the world. One example illustrates: across the whole world, infant diarrhea is one of the leading causes of death, whereas in the US viral diarrheas are experienced as mild illnesses requiring little if any medical attention for the vast majority of infants.
Now lets turn to the question of how infants fed with formula fare compared to those fed with breast milk in the United States, starting with health impacts. One of the largest studies on this questions is called the Promotion of Breastfeeding Intervention Trial (PROBIT) Study Group.
PROBIT compared how kids turned out at age 6.5 after looking at breast fed infants and sorting them by how long they nursed, this study looked at 17,046 infants in Belarus, a country near Russia and once part of the Soviet Union. This study, published in 2008 found that there was no difference in the chance of having or the severity if present of asthma, allergy, obesity, cavities, or ADHD.
On the issue of infection, the data are very clear that breast milk reduces the chance of infection, but in the United States this reduction is almost trivial. The top US agency that looks at health claims and quality outcomes is the Agency for Health Care Research and Quality, the AHRQ. In 2009 the AHRQ found that if you add up 5,400 hours of breast feeding, you prevent one ear infection compared to 5,400 hours of formula feeding. The number of hours difference to prevent one hospitalization for a respiratory infection was over 20,000 hours. In the United States formula fed infants simply do not get sicker at significant rates, from an infectious disease point of view it is safe to feed with infant formula.
On the issue of whether the choice of how to feed your baby impacts how well they will think later in life, the published data seem to be waging war back and forth. Several years ago, a study from New Zealand found that the more breast feeding the higher the IQ. The publication of this study fired up worries that use of infant formula could hurt actual brain development, but not long after a second publication found that essentially all the differences in IQ were the result of differences of the mothers’ IQ’s, because mom’s with higher IQ’s were more likely to nurse.
In the PROBIT study of babies in Belarus, a significant advantage in the ability to think at age 6.5 was found for babies who breast fed more.
But in an April 2017 publication in the AAP’s Pediatrics (http://pediatrics.aappublications.org/content/139/4/e20161848), a study of 8,000 babies in Ireland looked at a variety of detailed cognitive abilities in infants who were breast fed for varying lengths of time. The study looked at a detailed list of abilities to think including vocabulary, problem-solving skills, overall intelligence levels, hyperactivity, peer relationship quality, emotional symptoms, and conduct. At age 5 years old they found no difference in the ability to think or behave related to how much they were fed breast milk and how much they were fed formula.
American rates of breast feeding
Many will be surprised to learn that American mothers breast feed at rates very comparable to other modern Western societies. About 80% of mothers start off with breast feeding, and about 50% are doing so at 6 months old. Canada is at 50% at 6 months, Britain at 34%. According to the CDC, America exceeded most breast feeding goals by 2011. So there is no crisis of breast feeding in the US.
The Primacy of the Intimacy of Mother and Baby
If we look at all the above information, we need to return to what is actually happening at birth.
Every birth is the culmination of years of hopes and dreams, and months of pregnancy during which a lifetime of hopes and dreams are experienced with great intensity. Every mother, every father has lots of experience, love and hope as birth approaches, and hold their newborn with a depth of love and a sort of love they have never experienced before.
It is in this setting that parents decide how to feed their new child, this new person in the world.
My starting point as a doctor advising parents about this moment, is to start by saying the medical world should stay out of that beautiful moment as much as possible. Deciding how to feed your baby turns out to be the essence of an intimate moment, and unless there is some urgent medical need, doctors should stay out of that moment.
My reading of all the data pushing and pulling across breast feeding is that in the US, babies turn out fine either way. And therefore, I see no reason for me, or any other doctor, to push or pull parents in one direction or another on how to nourish your newborn. I think our job is to answer your questions, if you have any, and to support your decision whether it is to nurse, formula feed, or both.
I come this conclusion based on the extensive literature and the conclusions of serious review agencies like the AHRQ. They convince me that if anyone approached a group of kids in Kindergarten, or 4th grade, or high school and were permitted to test them for health and cognitive functions to any extent, they would be unable to determine who was breast-fed, who was formula fed, or who had both. If these groups are not actually distinguishable as they develop and grow up, on what basis can the medical world pressure parents of newborns in the matter of this choice?
My answer is that we should let parents make this personal decision on their own, with whatever support they seek from us, but under no pressure.
Breast milk remains a unique food source. There is no other food that is actually evolved to feed a newborn or infant, and it is the only food we ever eat that is made out of purely human material especially designed for newborn and infant growth and development. As such breast milk will always be the standard for what a baby should be eating.
At the same time, the science of making a fluid very, very similar to breast milk has been impressively successful. There is one formula for making this food, and it’s called infant formula. It works. It works very, very well. It works so well, that no one yet has been able to look at a group of older children and tell which were nursed or given formula. Studies on health outcomes in countries with clean water, easy access to formula, and well fed children find not enough difference between formula and breast fed infants to allow telling them apart later in life.
With regard to the infection question, it is a huge issue where malnutrition and starvation are rampant, but not much of one in modern, well fed societies. In the US in particular, breast fed infants may have fewer colds and stomach flus, but not many fewer. Sending a child to day care or school introduces a vastly greater number of viral infections to a child than formula feeding.
- Breast milk is a unique and incredibly special food. It is the only food evolved to meet all the needs of a newborn and infant.
We stand ready to support any family to achieve successful nursing, including access to one of our region’s most incredible and effective lactation counselors.
- Modern infant formulas all are made to the same specification, to match breast milk as closely as possible. Although clearly not identical to breast milk, in the United States, babies fed formula grow up and develop as well and normally as babies breast fed. Today’s formula works and works well.
- Recent studies confirm that it is hard to tell the difference between infants nursed or given formula later in life. That includes no substantial difference in intelligence, cognition, behavior, obesity, allergies, cavities.
- No study has ever demonstrated the ability of an investigator to take a group of older children or adults and after any testing being able to tell who was nursed and who was bottle fed reliably.
- Given the actual excellent outcomes seen in newborns and infants fed formula, we approach the moment a family decides how to feed their infant with the most profound respect. This decision is very, very deeply personal, and is the first decision that helps the mother, the parents, decide how best they will connect to their new child when they feed them. We have always, and will continue to, been there to help answer questions, but never to pressure. This is a moment of decision we feel parents should be free to make, and to feel good whether they nurse, bottle feed, or both.
Here is to all families loving their children, to the medical world staying clear of imposing itself, and working together to be as helpful as possible!
To your health,
Dr. Arthur Lavin