What nutrient is commonly low in commercial infant formulas?

The correct choice identifies iron as a nutrient that is often low in commercial infant formulas. Iron is critical for an infant’s growth and development, particularly for cognitive function and the formation of red blood cells. Breast milk provides adequate iron for infants in the early months, but as babies grow and their iron needs increase, they may require additional iron, especially if they are transitioned to formula or solid foods before the recommended age.

Commercial infant formulas are typically fortified with many essential nutrients, but they might not contain sufficient iron to meet the increased needs as infants grow. As a result, pediatricians often recommend the introduction of iron-rich foods or iron supplements to ensure that the nutritional needs of the infant are fully met, particularly after six months of age when iron stores from birth begin to deplete.

Other nutrients, like calcium, vitamin D, and protein, are generally included at adequate levels in formulas to support overall growth and development. Therefore, the focus on iron highlights its significance and the potential risk of deficiency if it is not adequately supplemented in an infant's diet.