“We found that differences in dietary habits start very early,” said Xiaozhong Wen, the study's lead author.
The researchers used data from the Infant Feeding Practices study, an in depth look at baby eating habits, which tracked the diets of more than 1,500 infants up until age one, and documented which of 18 different food types—including breast milk, formula, cow's milk, other milk (like soy milk), other dairy foods (like yogurt), other soy foods (like tofu), 100 percent fruit or vegetable juice, and sweet drinks, among others - their mothers fed them. Wen's team at the University at Buffalo focused on what the infants ate over the course of a week at both 6- and 12-months old.
In many cases, infants were fed foods that would surprise even the least stringent of mothers. Candy, ice cream, soda, and french fries, for instance, were among the foods some of the babies were being fed. Researchers divided the 18 different food types into four distinct categories, two of which were ideal for infant consumption—"formula" and "infant guideline solids"—two of which were not—"high/sugar/fat/protein" and "high/regular cereal." It became clear which babies tended to be fed appropriately, and which did not.
"The extent to which lower socioeconomic classes (i.e., low household income, low maternal education) are associated with unhealthy infant dietary patterns is substantial," said Wen.
The immediate danger resulting from poor infant diets is early weight gain and stunted growth. Larger weight increases were observed in the infants who consumed higher levels of fat and sugar, and dairy foods (both of which were associated with poorer households and less educated mothers), especially at age one. Those same babies were found to be shorter on average, possibly, the researchers believe, because of a lack of foods that help promote proper bone growth.
The longer term problem with the discrepancy in infant dietary patterns is that these differences—specifically the exposure to certain unhealthy foods, and lack of exposure to certain other healthy ones—can negatively impact a child's long-term health, eating habits, and food preferences.
A follow up to the Infant Feeding Practices study, which analyzed data for the same children at age six, found that infant feeding patterns appear to translate into similar childhood eating habits. And those preferences can last a lifetime.
"If you tend to offer healthy foods, even those with a somewhat bitter taste to infants, such as pureed vegetables, they will develop a liking for them. But if you always offer sweet or fatty foods, infants will develop a strong preference for them or even an addiction to them," Wen said in the statement.
What's going on? The reason such discrepancies exist appears to be the result of a number of factors. For one, lower education levels are likely tied to poorer awareness of proper nutrition and infant feeding practices. If parents don't have a proper understanding of what infants should be eating, and how important proper nutrition is for a child's short- and long-term health, it's hard to expect them to choose healthier foods when less healthy ones might be more convenient.
Price could also be a leading factor. The researchers note that the reason lower-income households are more likely to feed their infants foods that are high in sugar and fat might simply be because those items are relatively inexpensive.
The gap between what the poor and rich feed their babies is an extension of a troubling and growing systemic problem in the United States. The tentacles of income inequality find their way into many different aspects of life, and food is a particularly apt example. Food inequality, whereby America's wealthiest people eat well, while the country's poorest eat, well, poorly, is not only real, but worsening. The key to breaking that cycle could lie in understanding that that gap begins to grow before a baby turns one year old and that poor feeding habits in early childhood tend to translate into poor eating habits later in life.
"Infancy is a critical period to learn various food tastes" said Wen. "Parents should take advantage of this period (when they have high control of what their infant can eat) to develop a life-long preference for healthier foods."