On a US label, identify the reference behind a reduced-sodium claim

Reduced sodium is a comparison. Before using it to choose between packages, identify the food being used as the reference. The reference might be the manufacturer's regular version, rather than the other product you are holding. Without that identity, a percentage leaves the central shopping question unanswered.

Find the comparison the package actually makes

For conventional foods other than meals and main dishes, 21 CFR 101.61(b)(6) requires at least 25% less sodium per reference amount customarily consumed than an appropriate reference food. It also requires the reference identity and percentage near the prominent claim, plus quantitative comparison information. A reference that qualifies as low sodium cannot support this reduced-sodium claim.

The general relative-claim rules in 101.13(j) require a similar food for reduced claims. This prevents an arbitrary high-sodium food from becoming your comparison baseline. Meal and main-dish claims have a separate per-100-g branch in 101.61(b)(7).

Build a reference card before calculating

• Copy the full reduced-sodium wording and any nearby comparison phrase.
• Name the reference product exactly, including regular recipe or other qualifiers.
• Record both sodium amounts with their food quantities and preparation states.
• Mark whether the quantities describe the applicable reference amount or the labeled serving.

For an invented exercise, assume an ordinary packaged food and its appropriate regular reference use the same 40 g reference amount and labeled serving. The reference contains 400 mg sodium and the new version 280 mg. The reduction is (400 − 280) ÷ 400 × 100 = 30%. That arithmetic exceeds the 25% comparison threshold, under the stated assumptions; it does not certify the complete label.

Ask your separate shopping question

Now suppose another fictional product has 220 mg sodium per 40 g but carries no reduced-sodium statement. It has the lower displayed amount in this equal-quantity comparison, even though the first product advertises a reduction. Your comparison and the manufacturer's comparison have different baselines.

If the reference product is missing, record reference unknown and ask the manufacturer which product and amounts support the claim. Do not invent an earlier recipe from the current panel. This guide covers FDA-regulated US conventional-food wording, not every jurisdiction or a personal sodium target.

For an app-assisted label-reading workflow, download Ingredi AI from the App Store or Google Play. Keep the reference card beside any output: a scan cannot supply a comparison product that the evidence does not identify.