Sodium vs. Salt on Electrolyte Labels: What the Numbers Mean

Sodium and salt are different measurements. In the common food-label conversion, 500 mg sodium corresponds to about 1.25 g salt-equivalent. That does not prove a drink contains 1.25 g sodium chloride, because sodium can come from several ingredients. Keep the substance and the unit attached to every number. [1] [2]

This is why an electrolyte label can look confusing even when its numbers are consistent. “Sodium” names an element. “Salt” can mean sodium chloride in the kitchen, while a nutrition declaration may use a calculated salt-equivalent value.

First separate milligrams from grams

One gram equals 1,000 milligrams. That unit conversion does not change the substance being measured: 500 mg sodium is 0.5 g sodium. Only after keeping the substance clear should you make a sodium-to-salt conversion.

NHS guidance uses the factor of 2.5. It is a convenient conventional conversion based on the relationship between sodium and sodium chloride, not a rule that the entire ingredient list must consist of table salt. [1]

Salt-equivalent does not reveal the recipe

Imagine a fictional packet declaring sodium 500 mg, with sodium chloride and sodium citrate listed as its sodium sources. The declared total tells you how much sodium the serving supplies. It does not tell you how that sodium is divided between the two sources.

Multiplying by 2.5 still gives 1.25 g salt-equivalent. It does not establish the actual mass of sodium chloride or sodium citrate. Those compounds contain other elements as well as sodium, and a total sodium line does not disclose their proportions.

European Commission guidance makes the distinction explicit for food-label calculations: salt-equivalent is calculated from total sodium, including sodium originating in ingredients other than sodium chloride. This explains a labeling convention; it does not mean every country or supplement category uses the same panel format. [2]

Compare the same serving before comparing the amounts

Suppose a second fictional product declares salt 1.25 g per packet, using that same salt-equivalent convention. Its corresponding sodium amount is 0.5 g, or 500 mg. On that specific basis, the sodium amounts match the first example.

That conclusion depends on both declarations applying to one packet. If one amount is per packet and the other is per 100 mL of prepared drink, they cannot be compared directly. Read the serving basis and preparation instructions before deciding that the larger-looking number supplies more sodium.

Likewise, 500 mg of table salt would correspond to about 200 mg of sodium using the same approximate factor. Substituting “salt” for “sodium” without a conversion can create a substantial error.

A Daily Value percentage has its own denominator

The general U.S. Daily Value for sodium is 2,300 mg. A serving with 500 mg sodium supplies 500 ÷ 2,300 × 100 = approximately 22% of that Daily Value. It is not a statement that the powder is 22% salt by weight. [3]

The Daily Value is a nutrition-label reference, not a personalized exercise-replacement target. The percentage and the sodium amount answer related questions, but neither tells you how much of an electrolyte product you personally need.

Use three checks when a label looks inconsistent

Ask what substance the number describes, whether the unit is mg or g, and what serving or prepared volume it applies to. Those checks often resolve the apparent contradiction without guessing at the formulation.

If directions also use milliliters, remember that mL measures liquid volume rather than sodium mass. Our guide to reading a marked liquid measure explains that separate distinction. To connect volume with an ingredient amount, you still need the particular product’s concentration or per-serving declaration.

A salt-equivalent calculation is useful for comparing sodium declarations. Treat it as that calculation, and use the ingredient list and manufacturer’s actual specifications for questions about the salts inside the product.

Sources

1. Cambridge University Hospitals NHS Foundation Trust. No added salt diet: converting sodium to salt.
2. European Commission. Notice on questions and answers on Regulation (EU) No 1169/2011, section 3.2.4: salt calculation uses sodium from all ingredients.
3. FDA. Daily Value on the Nutrition and Supplement Facts Labels.
4. FDA. Dietary Supplement Labeling Guide, Chapter IV: Nutrition Labeling.