FDA proposes new infant formula limits for iodine, vitamin A, D and manganese

The Food and Drug Administration has proposed to change the required amounts of several nutrients in infant formula. A proposed rule published in the Federal Register on 2 November 2026 would, if finalised, amend the minimum and maximum levels for four nutrients and, for the first time, set a maximum level for one of them [s1]. The agency describes the action as part of a "phased, comprehensive review of infant formula nutrients" carried out under its Operation Stork Speed initiative [s1].

Infant formula in the United States must meet nutrient specifications set in federal regulation because, for many babies, it is the sole source of nutrition. The proposal assesses 8 of the 30 required nutrients and says FDA "intends to address the remaining infant formula nutrient specifications through subsequent proposed rules followed by one final rule" covering all the changes [s1]. The review covers formula meant to feed infants from birth through 12 months of age.

The four nutrients that would change

For iodine, FDA proposes to amend 21 CFR 107.100(a) "to increase the required minimum to 15 [micro]g/100 kcal and decrease the required maximum to 50 [micro]g/100 kcal" — that is, 15 to 50 micrograms per 100 kilocalories [s1]. Iodine is an essential component of thyroid hormones, which the document notes regulate processes including protein synthesis and enzymatic activity.

For vitamin A, the agency proposes to "decrease the required minimum to 70 [micro]g RAE/100 kcal (233 IU/100 kcal) and decrease the maximum specification to 120 [micro]g RAE/100 kcal (400 IU/100 kcal)" [s1]. It would also change the unit of measure and, in a newly established section 107.100(g), "change which forms of vitamin A may contribute to the minimum and maximum vitamin A content calculations from both preformed vitamin A and beta-carotene to preformed vitamin A only" [s1].

For vitamin D, FDA proposes to "increase the required minimum to 2 [micro]g/100 kcal (80 IU/100 kcal) and to increase the required maximum to 3 [micro]g/100 kcal (120 IU/100 kcal)," and to change the primary unit of measure from international units to micrograms [s1].

For manganese, the agency proposes to "decrease the required minimum level for manganese to 1 [micro]g/100 kcal and establish a maximum level for manganese in infant formula of 50 [micro]g/100 kcal" [s1]. Current federal rules set no upper limit for manganese, so this would be the first ceiling for that trace mineral.

Four nutrients reviewed but left unchanged

The proposal also reports a "comprehensive assessment of four additional nutrients — chloride, selenium, potassium, and sodium — for which we conclude that the current required levels remain appropriate" and reflect the best available evidence on infant nutritional requirements and safe intake levels [s1]. For those four, the existing specifications would stand.

What the figures mean, and what they do not

The numbers are expressed per 100 kilocalories because formula requirements are defined relative to the energy a baby consumes rather than per bottle. Several of the changes tighten the permitted range: iodine and manganese would gain or keep a maximum, and vitamin A's ceiling would come down. Others shift the whole band, as with vitamin D's higher floor and ceiling. The change to vitamin A's "permitted source" is technical but consequential for manufacturers, because it narrows which chemical forms can count toward the requirement.

A proposed rule is not in force. It states FDA's current position and opens the matter to public comment before any final rule is written. The agency "invites comment" on its approach, including the proposed timeline for compliance [s1].

Timeline and how to comment

Comments must be submitted by 2 March 2027; the electronic docket will accept them "until 11:59 p.m. Eastern Time at the end of March 2, 2027" [s1]. The rulemaking carries Docket No. FDA-2026-N-10832 and RIN 0910-AJ34, and comments may be filed through that docket [s2].

If a final rule follows, FDA intends it to "become effective 60 days after the date of the final rule's publication," with a proposed compliance date of "3 years after the effective date of the final rule completing our phased, comprehensive infant formula nutrient review" — time, the agency says, for industry to reformulate and relabel [s1].

The fixed points for now are the proposal itself and its deadline: revised minimum and maximum levels for iodine, vitamin A, vitamin D and manganese, a new manganese ceiling, unchanged specifications for chloride, selenium, potassium and sodium, and a comment period that closes on 2 March 2027.