The Food and Drug Administration has proposed the first big update to baby formula nutrient rules in nearly 30 years, ABC News, CNN and the agency report. The plan covers eight of the 30 nutrients that formula must contain, the FDA says.

The rule would update the levels for vitamin A, vitamin D, iodine and manganese, ABC News reports. It would keep the current rules for chloride, potassium, selenium and sodium. It would also change the units used to measure two nutrients, the FDA says.

The FDA is also asking for views on three add-ins that some makers already use but are not required, the outlets report. They are DHA, ARA and L-carnitine. The FDA says there is evidence they help a baby's brain grow.

"Parents deserve confidence in every bottle they feed their baby," Health Secretary Robert F. Kennedy Jr. said, ABC News reports. "We will hold infant formula manufacturers to rigorous scientific standards and put babies' health first."

This is the first of three phases, the FDA says. Later phases will look at the other nutrients, new ones and sources of sugar in formula. The FDA plans one final rule at the end, and makers would get three years to change their formulas and labels. The public has 120 days to comment, the agency says.

The FDA also released new test data and found that most formula samples had "low or non-detectable levels of chemical contaminants," ABC News reports. The review is part of an effort the FDA calls Operation Stork Speed, the outlets report.

What we know: The FDA wants new levels for four formula nutrients and is taking comments for 120 days.
What we don't: When a final rule will come and how formula makers will respond.