While breast milk is still best for babies, improper storage may actually put infants at risk, says a study by Dr. Alexander Penn of the University of California. The study’s findings were presented during the annual conference of the American Society for Parenteral and Enteral Nutrition.
According to the study, breast milk stored in the refrigerator for one day or frozen for three consecutive days decreases the milk’s quality, even increasing the risk for inflammation of the colon and small intestine, also known as enterocolitis.
Lipase, an enzyme in milk, degrades milk solids into unbound fatty acids, which may cause cell death or cytoxicity in babies’ intestines. Premature babies, especially, are more vulnerable to such risks.
Penn and his co-researchers used enzymes lipase and protease, together with saline solution to test the digestion of both frozen and refrigerated breast milk. Breast milk stored for three days at 4 degrees Celsius showed cytoxicity at 41 percent while breast milk frozen for three days at -20 degrees Celsisus had 18.5 percent cytoxicity. Cytoxicity is a substance’s quality of being toxic to cells.
Comparing the cytoxicity of breast milk versus infant formula, though, breast milk is still best for babies. Says Penn, “So I'd say that if my only choice was stored breast milk or formula, I'd still go with the breast milk.” He adds, “As a food, fresh breast milk seems amazingly well-designed to deal with this very issue.”
Freshly expressed breast milk, as well as breast feeding directly is still the safest and most risk-free method, versus feeding stored milk.
Standards from the U.S. Centers for Disease Control and Prevention posits that milk should be refrigerated no longer than five days and at 4 degrees Celsius. If stored for 6 to 12 months, on the other hand, it should be stored at -20 degrees Celsius.
•February 1, 2012. “Stored breastmilk can become cytotoxic” health24.com
•February 20, 2012. Dr. Diana Sarmiento. “Breast milk still best for babies” ph.she.yahoo.com