Prolonged formula feeding may increase the risk of leukemia

by Julie Snyder

FormulaIn the 20th century, when formula feeding first became widespread in the United States, it was touted as a scientific advancement. Physicians endorsed it as a nutritional improvement for the modern infant.

Now, a hundred years and thousands of scientific studies later, we know that feeding formula can be detrimental to your baby's health.

A research team in the Department of Nutritional Sciences at the University of Texas at Austin added one more study to that list. They found that prolonged formula feeding may increase the risk of acute lymphoblastic leukemia.

"For every month that a child was fed formula...we found that the risk for this type of cancer was higher," commented lead investigator Jeremy Schraw from the University of Texas at Austin. The recognized association between breastfeeding and immune system development may explain the findings. "If a baby is fed only formula, he or she will not be getting any immune factors from the mother, which could be leading to this greater risk."

Acute lymphoblastic leukemia

Acute lymphoblastic leukemia is a fast-growing cancer of white blood cells called lymphocytes. It's the most common form of childhood cancer, typically affecting children between the ages of 3 and 7.

Previous literature suggested an association between infant feeding patterns and the normal development of the immune system. The intent of this study was to examine the association between infant feeding practices and age at introduction of solids, on risk of ALL.

About the study

Schraw and colleagues surveyed 142 children from the Texas Children's Cancer Center and the National Children's Study in Houston, San Antonio and Austin, Texas, who had been diagnosed with acute lymphoblastic leukemia and 284 children without ALL.

In this ethnically diverse population, the duration of formula feeding and age at introduction of solid foods were directly associated with increased odds of ALL. The research does not prove a cause-and-effect relationship.

✓ Each additional month of feeding formula raised cancer risk by 16 percent (10.0 months versus 6.2)
✓ Each additional month of delaying solid food increased risk by 14 percent (8.6 months versus 7)

Evaluation of feeding patterns showed no differences in the proportion of patients and the control group who were breastfed exclusively, fed formula exclusively, or received breast milk and formula. Schraw and colleagues also found no difference in the duration of breastfeeding and the incidence of ALL.

The study is considered preliminary and has not been published in a peer-reviewed journal.

The investigators say further research needs to address the factors influencing duration of formula feeding and delay in introduction of solids.

We agree that more investigation is needed. While the formula industry is not in any immediate danger, we do hope that parents will press for more research and continued improvements to enable everyone to have the healthiest start possible.

Do you believe that this will impact your decisions for feeding your baby? What would you like to see formula companies do with this information?

Medical references:
- Schraw J, et al "Longer formula feeding and later age at introduction of solids increase the odds ratio of pediatric acute lymphoblastic leukemia." American Association for Cancer Research Frontiers in Cancer Prevention Research Abstract A102.

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