Claims that promise an amount

Three sodium claims describe what is actually in the food. Each one is measured against a standard serving size that FDA sets for the food category, called the reference amount customarily consumed. Two brands of the same food are held to the same yardstick.

1. 1 Sodium free means less than 5 mg of sodium per reference amount and per labeled serving. The food also cannot contain an ingredient that is salt, or an ingredient generally understood to contain sodium, unless the label carries an asterisk explaining that the ingredient adds a trivial amount of sodium.
2. 2 Very low sodium means 35 mg or less of sodium per reference amount.
3. 3 Low sodium means 140 mg or less of sodium per reference amount.

Salt free is not a looser version of sodium free. A food may use the words salt free only if it meets the sodium free definition. Salt here means sodium chloride, the specific compound, while sodium is the mineral that can arrive through many other ingredients.

There is a second rule worth knowing about these claims. If a food is naturally sodium free, or naturally low in sodium, without any special processing, the label has to make clear that all foods of that type qualify, not just that brand. That is why you occasionally see phrasing along the lines of leaf lettuce, a sodium free food. The wording exists so a company cannot take credit for something the plant did.

Rounding is the last piece. Under FDA's labeling rules, sodium is declared as zero when a serving contains less than 5 mg, rounded to the nearest 5 mg between 5 and 140 mg, and rounded to the nearest 10 mg above 140 mg. A label that reads 0 mg can hold up to 4 mg per serving, which is genuinely negligible. The same rule matters more at the other end: a product listing 480 mg and one listing 490 mg are, for practical purposes, tied. Do not switch brands over 10 mg.

Claims that promise only a comparison

Reduced sodium, less sodium, light in sodium, and lightly salted are relative claims. They tell you about a change, not a level. The regulation sets how big the change has to be.

1. 1 Reduced sodium or less sodium means at least 25 percent less sodium per reference amount than an appropriate reference food, usually the regular version of the same product or a typical version of that food.
2. 2 Light in sodium means the sodium content is reduced by 50 percent or more compared with the reference food.
3. 3 Lightly salted means 50 percent less sodium than is normally added to that food.

Relative claims come with disclosure requirements that work in your favor. The label has to identify the reference food and state the percent or fraction of the reduction right next to the most prominent claim. It also has to carry a clear quantitative comparison of the amounts, along the lines of sodium lowered from 300 mg to 150 mg per serving. So the two numbers you want are printed on the package by law. Read them instead of the adjective.

One protection is built into the general rules for nutrient content claims: a relative claim for a lower level of a nutrient may not be used at all if the reference food already meets the definition of low for that nutrient. In plain terms, a package saying reduced sodium tells you the comparison product was above the 140 mg low sodium line. Otherwise the claim would not have been allowed.

The word light deserves its own caution. If the reference food has more than 40 calories or more than 3 grams of fat in a serving, a sodium claim has to read light in sodium, with the words in uniform type size, rather than light by itself. Light alone may stand for a 50 percent sodium cut only when the reference food is already 40 calories or less and 3 grams of fat or less. On a full calorie, full fat product, light by itself is a statement about calories or fat, not sodium.

Lightly salted has a companion rule. When a lightly salted product does not qualify as low sodium, the statement "not a low sodium food" has to appear next to the Nutrition Facts panel. FDA is telling you directly that the claim and the sodium level are different questions.

A relative claim on a salty food is still a salty food

Reference data from the US Department of Agriculture makes the point with numbers. Regular soy sauce made from soy and wheat runs about 5,490 mg of sodium per 100 grams. A lower sodium version of the same product in the same database runs about 3,600 mg per 100 grams, roughly a third less. That is a real reduction, and a shopper who uses the lower sodium bottle takes in meaningfully less sodium.

It is also nowhere near a low sodium food. Using a tablespoon of about 16 grams, the regular product lands somewhere near 880 mg of sodium in one tablespoon and the lower sodium version near 575 mg, which is roughly a quarter of the entire Daily Value in a single tablespoon. A product with those numbers cannot be labeled low sodium, because that claim requires 140 mg or less. It would be labeled less sodium or reduced sodium, and it would be telling the truth.

That gap between a percentage cut and an absolute amount is the single most common misreading of a sodium label. Twenty five percent less of a large number is still a large number.

No salt added and unsalted describe the factory

No salt added, unsalted, and without added salt are the most misunderstood phrases in the aisle, because they describe what happened during production rather than what is in the can. FDA allows them under three conditions: no salt is added during processing, the food is normally processed with salt, and when the food is not sodium free, the statement "not a sodium free food" or "not for control of sodium in the diet" appears next to the nutrition label.

Read that third condition as FDA telling you what the phrase does not mean. Vegetables, beans, tomatoes, dairy, meat, and poultry all carry sodium that occurs naturally in the food. A no salt added canned vegetable usually has far less sodium than the salted version, sometimes a very large difference, but it is not a zero.

The phrase is also specific to salt, meaning sodium chloride. Sodium reaches food through other ingredients too, including baking soda, which is sodium bicarbonate, and various sodium containing preservatives and flavor ingredients. The Nutrition Facts panel counts all of them in the sodium line. That is one reason the milligram number is the final word and the front of the package is a starting point.

When you see the not a sodium free food disclosure, take the hint and read the number. When you see no salt added on a food that is naturally very low in sodium anyway, such as plain frozen vegetables, the phrase is accurate but is not doing much work.

The serving size hidden inside every claim

Every sodium claim is judged per reference amount customarily consumed. FDA sets that amount by food category, based on what people typically eat, so companies cannot invent a flattering serving to qualify for a claim. If the serving size printed on a particular package differs from the reference amount, the claim has to be followed by the criteria it met.

Small serving foods get an extra test. For a food with a reference amount of 30 grams or less, or 2 tablespoons or less, the very low sodium and low sodium claims must also be met per 50 grams of food. That rule is aimed squarely at condiments, seasonings, and sauces. A dressing cannot earn a low sodium claim simply by declaring a one teaspoon serving.

None of this changes the fact that the amount you eat is the amount that counts. Separate articles in this series cover how serving sizes are set and how to work out the sodium in the portion you actually put on the plate.

What healthy on the front of the package now means

Healthy is a regulated claim, and its definition changed. FDA published an updated rule in December 2024 that ties the word to two things: a food has to contain a minimum amount from a recognized food group, and it has to stay under limits for sodium, saturated fat, and added sugars. Use of the claim is voluntary.

The sodium limits FDA describes for the updated claim are 230 mg per reference amount for an individual food, which is 10 percent of the Daily Value, 345 mg for mixed products, and 690 mg for meals. The compliance date is February 25, 2028, and manufacturers may use the new criteria before then. During the transition, some packages will be using the older definition and some the newer one.

Notice where 230 mg sits. It is above the 140 mg cutoff for low sodium. A food carrying the healthy claim is not automatically a low sodium food, and a meal carrying it can supply 690 mg, about 30 percent of the Daily Value, in one sitting. The claim is a useful screen. It is not a sodium measurement.

Sea salt, kosher salt, and words with no sodium meaning

Salt names on the front of a package tend to imply something about sodium that is not there. The American Heart Association states that table salt, kosher salt, and most sea salts are about 40 percent sodium. Larger crystals can mean less sodium per teaspoon, simply because fewer crystals fit on the spoon, but by weight the products are close to each other. The organization's advice is the same as everywhere else on the label: compare the Nutrition Facts panels.

Salt free seasoning blends are a different matter, because that claim is defined. A blend using those words has to meet the sodium free standard of less than 5 mg per serving. Some of these products replace part or all of the salt with potassium chloride. If you have kidney disease, heart failure, or take a medicine that affects potassium, including certain blood pressure medicines and diuretics, ask your health care professional or pharmacist before using a potassium based substitute regularly.

Words that FDA has not defined in terms of sodium, including natural, artisan, homestyle, and farmhouse, tell you nothing at all about sodium. Neither does the absence of a claim. Plenty of lower sodium products say nothing on the front.

Turning the words into a decision

Here is the sequence that works in the aisle, in about 15 seconds per product.

1. 1 Read the front of the package as a filter, not an answer. Absolute claims, meaning sodium free, very low sodium, and low sodium, tell you the food meets a fixed limit. Relative claims, meaning reduced, less, light in sodium, and lightly salted, tell you only that it beats another product.
2. 2 On any relative claim, find the two milligram figures the label is required to show and compare them yourself.
3. 3 Turn the package over and read servings per container, then serving size, then sodium in milligrams, then percent Daily Value. Use 5 percent or less as low and 20 percent or more as high.
4. 4 Treat a difference of 10 mg or less between two products as a tie, because of label rounding.
5. 5 When a package carries the not a sodium free food or not a low sodium food disclosure, let the milligram number decide.
6. 6 Check again in a year or so on products you buy often, because recipes get reformulated and the sodium figure on a familiar package can change without any change to the front of the box.

The numbers behind all of this are worth holding onto. FDA puts average US intake at about 3,400 mg of sodium a day, against a Daily Value of less than 2,300 mg, and reports that more than 70 percent of what Americans take in comes from packaged and prepared foods rather than the salt shaker. The American Heart Association recommends no more than 2,300 mg a day, describes 1,500 mg as an optimal goal for most adults, and says that for most people cutting back by 1,000 mg a day can improve blood pressure. The 2025 American Heart Association and American College of Cardiology high blood pressure guideline estimates that sodium reduction is associated with a drop of roughly 6 to 8 mm Hg in systolic pressure, the top number, among people with high blood pressure.

Because so much of that sodium arrives in packaged food, the words on the package are one of the few levers a shopper controls directly. If you have kidney disease, heart failure, or take a diuretic, ask your care team what daily sodium target fits your situation, since a personal target can differ from the labeling reference value of 2,300 mg.