Adding omega-3 fatty acid, DHA to infant formula may be beneficial according to a new study, but breastfeeding experts say they will still recommend a more natural and healthier source of DHA: breast milk.

The study indicates that babies getting a formula supplemented with DHA performed better on a cognitive test than infants who were given formula without it. DHA occurs naturally in breast milk.

Doctors show concern over marketing a replacement for breast milk they say the evidence may support formula containing a DHA supplement over formula without one.

One of the pediatrician noted that few mothers are convinced that the new formula with the supplement is actually superior to breast milk.

"It is clear that the food industry fascination with nutraceuticals (strategically fortified food products) is now spreading into infant formula," said Barbara Moore, president and CEO of Shape Up America!, in an e-mail to ABCNews. com.

Infants who display superior performance on the means-end problem solving task tend to have a higher IQ level and it's possible that the beneficial effects of DHA go on beyond infancy.

There have been sharp criticism against the launch of any product that may be a supplement for breast feeding. Dr. Ruth Lawrence, a neonatologist at the University of Rochester Medical Center and the American Academy of Pediatrics pokeswoman on breast-feeding, said that DHA may contribute to better formula, but that won't replace breast milk.