Low-Calorie Infant Formulas Won't Solve Child Obesity

Just decreasing calories won't replicate the protective effect of breast milk.

Earlier this year, infant formula company Abbott Laboratories announced it will be reducing the caloric composition of its most commonly used formulas.

The new Similac formulas will have only 19 calories per ounce rather than 20 calories per ounce. The new formula is scheduled to hit the shelves by July of 2014. Similac claims that the new formulation will make formula more like breast milk, which has been shown to have a protective effect against lifelong obesity. And more than one-third of American children are overweight, despite First Lady Michelle Obama’s public efforts to encourage healthy eating. That means roughly 25 million American children are overweight or obese.
With more than two-thirds of Americans dealing with obesity, Abbot Laboratories’ strategy may seem wise to some. But it doesn’t address the bigger contributor to obesity: rapid growth in infancy. According to a classic study, every 100 grams an infant is over birth weight at one week of life increases the adult risk of obesity by 28 percent.
Formula feeding costs a family $800 to $2800 per year on average, and some infants, particularly premature ones, need to get a particular number of calories in order to grow. For many American families, getting the same number of calories using this formula could require paying an extra $140 per year. While this may not seem like much, with more than two million infants receiving governmental assistance for feeding, the cost to society could be more than $100 million.

Breastfeeding prevents rapid excessive growth, but not because of caloric density. While food bought at the grocery store, including prepared formula, contains a specific, quantifiable amount of calories, there are significant variations in the caloric density of breast milk over time and from person to person.
Breastfed infants are inherently protected from excessively overfeeding in their early days, because a mother’s milk comes in gradually, allowing a natural weight loss during the first week of life. The process of an infant obtaining the milk from the breast also requires greater metabolic activity on the part of the infant. This pattern of feeding and growth is difficult to replicate.
Existing studies show that reducing caloric density does not result in fewer calories consumed. Premature infants are likely to take greater volumes when drinking less calorically dense formulas. This results in a greater cost to parents and no overall decrease in consumption of calories.
In older children aged 2-4 years, studies have shown that reduced calorie milk is associated with more obesity. Similar results have been found in adults who drink diet soda. Lower calorie drinks result in less satiety, causing people to consume calories elsewhere.
This isn’t to say that the idea of feeding infants fewer calories doesn’t merit consideration. Infants are less metabolically active today. Between important safety recommendations and a surge in baby products, today’s infants likely spend much more time immobilized in car seats, sleeping on their backs, and watching television in their automatically rocking swings.  Many infants spend little time on the floor playing, or being actively carried which requires balance and periodic shifting of weight.

But it is a big leap to declaring that the answer is to feed infants less rather than increasing their activity when it is safe to do so. An infant’s brain is still growing, and attempting to limit calories is not the wisest choice. This is critical especially because there is no evidence that lowering caloric density will actually decrease caloric consumption.

Conquering obesity will take a multifaceted approach. One such plan is advocated by the CDC’s Healthy People 2020 goals. This 10-year plan with 1,200 objectives advocates for hospital, community, and workplace practices that support breastfeeding, and national practices that support access to healthy foods and safe areas for play.

While attempts to make formula more like breast milk are noble in theory, calorie manipulation alone cannot replicate the daily variations in breast milk composition. It is unlikely to affect obesity. We may just find ourselves paying more for the same calories.