Infant girls who are given baby formula containing soy could be at risk for severe menstrual cramping later in life, a new study has found.
Researchers studied more than 1,500 African American women to study the effects of soy formula, following up on previous studies that had focused mostly on white women. As Reutersreported, they found that babies who were given soy formula had a 40 percent greater risk of using hormonal contraception for severe menstrual pain and a 50 percent greater risk of severe menstrual discomfort during periods.
“We observed that soy formula feeding during infancy was associated with several indicators of severe menstrual pain in reproductive age women,” said Kristen Upson, a researcher with the National Institute of Environmental Health Sciences.
The research found that the painful symptoms showed up by the time the women were between the ages of 18 and 22. Researchers believe that introducing soy at such a young age may have affected the continued growth of the reproductive system that takes place after a baby is born.
“The link between soy formula feeding in infancy and menstrual pain in adulthood may be biologically plausible given that in the early months after birth, an infant’s reproductive system continues to develop and an infant’s nutrition primarily consists of breast milk and/or formula,” Upson told Reuters in an email.
This is not the first study to focus on the potential long-term effects soy baby formula. A study published earlier this year showed that infants who were given soy-based baby formula as newborns had differences in reproductive-system cells and tissues compared to babies given cow milk formula or were breastfed. As Science Daily noted, the differences were not seen as a risk, but were still notable to researchers who believed that more study was needed.
“The researchers say the differences, measured in the months after birth, were subtle and not a cause for alarm, but reflect a need to further investigate the long-term effects of exposure to estrogen-like compounds found in soy-based formulas,” noted the executive summary of the study.
Slate also tackled the controversy around soy-based baby formula in a 2017 report, noting that while this type of formula has become increasingly popular, the long-term effects are still not known. The report noted that soy-based baby formula now makes up 12 percent of the market for formula in the United States, with a number of new brands being introduced to meet the growing demand among consumers.