What 'Fortified' Actually Means in a Nutrient Database

On this site, "fortified" isn't a marketing word — it's data. Nine nutrients here have a dedicated ", added" field, separate from the naturally occurring amount, including Vitamin B-12, added. A SlimFast shake mix in this database carries 8.08 micrograms of added Vitamin B-12 per 100g, sourced from the product's own label claim.

What does "added" actually mean as a tracked data field, not just a word?

This project's nutrient table carries nine nutrients with their own dedicated ", added" entry, each a separate row from the naturally-occurring version: Calcium, added; Iron, added; Niacin, added; Riboflavin, added; Sugars, added; Thiamin, added; Vitamin B-12, added; Vitamin C, added; and Vitamin E, added. Vitamin B-12, added is a genuinely separate database record from Vitamin B-12 itself — they have different nutrient ids, different values, and on a food that's fortified, both can appear on the same nutrient table at once: one line for what's naturally in the food, a second line for what was put there deliberately. That split only exists for these nine nutrients; fortification of anything else in this dataset has to show up a different way, covered below.

What does a real fortified product actually look like in this data?

Querying fndds_ingredient_nutrient_value for Vitamin B-12, added (nutrient code 578) with a nonzero value turns up real commercial products. A SlimFast shake mix, powder, 3-2-1 Plan carries 8.08 micrograms of added B-12 per 100g, sourced to "SR Legacy." A Kellogg's Special K20 protein powder carries 8.3 micrograms, sourced to "SR28," an earlier Standard Reference release. A Slim-Fast Optima meal bar carries 7.9 micrograms. These aren't estimates or category averages — they're the specific figure tied to that specific product's record.

Can a Foundation Food — not just a branded survey item — be fortified too?

Yes, and this dataset has a clean example: Milk, reduced fat, fluid, 2% milkfat, with added vitamin A and vitamin D is a genuine, lab-sampled Foundation Food, not a survey ingredient, and it's fortified. Its own nutrient table shows Vitamin D3 at 1.1 micrograms per 100g with an "Analytical" derivation — independently lab-measured, not just copied from a label — Vitamin A, RAE at 83 micrograms marked "Calculated," and the combined Vitamin D (D2+D3) figure at 1.1 micrograms marked "Summed." Notice what's missing: there's no "Vitamin A, added" or "Vitamin D, added" field anywhere in this dataset's nutrient list. USDA only built dedicated ", added" tracking for the nine nutrients named above; vitamin A and D fortification instead folds directly into the ordinary Vitamin A and Vitamin D values, which is exactly why this milk's elevated vitamin D reading shows up as a normal-looking nutrient line rather than a flagged "added" one. Querying this project's own food_nutrient table for all nine dedicated ", added" nutrients (Calcium, Iron, Niacin, Riboflavin, Sugars, Thiamin, Vitamin B-12, Vitamin C and Vitamin E, added) turns up zero rows — meaning none of the 469 Foundation Foods currently in this database has a measured value in any of those nine fields. In this dataset, the dedicated "added" tracking exists entirely on the Survey/FNDDS side; every one of this guide's added-nutrient examples above is an FNDDS ingredient, not a Foundation Food, and the milk's own fortification shows up the other way, through its regular Vitamin A/D values instead. That's a distinction neither this guide's nutrient pages nor the food page states on its own — you only see it by comparing the two fortification mechanisms side by side.

What does the derivation code tell me about how trustworthy a fortified number is?

This project's food_nutrient_source table defines a category specifically for this situation — "Value manufacturer based label claim for added nutrients," one of ten broad source categories a value can carry in this dataset's schema — distinct from "Analytical or derived from analytical," the category covering the milk's own Vitamin D3 reading above. The milk example shows both ends of that spectrum on one product: Vitamin D3 independently lab-measured, Vitamin A calculated from other values, Vitamin D (D2+D3) summed from components. None of the nine dedicated "added" nutrients currently carry a value in this site's Foundation Foods table (see above), so for the FNDDS examples in this guide specifically, the ingredient page's "Source" column — "SR Legacy," "SR28," and so on — is the actual record of provenance you can check today, rather than a derivation code. In plain terms: a fortified value and the figure that comes with it are two separate pieces of information, and this dataset gives you a column for each.

Who actually needs to pay attention to added nutrients, and why does USDA bother tracking them separately?

MedlinePlus's Vitamin B12 encyclopedia entry states plainly that "Vitamin B12 is not present in plant foods unless fortified," and that "fortified breakfast cereals are a readily available source of vitamin B12" for people who don't eat animal products. The same entry lists people on a vegetarian or vegan diet, adults over 50, and people with certain digestive conditions among those at higher risk of low B-12 status. That's the practical reason a database bothers distinguishing "added" from "naturally occurring" at all: for someone tracking whether they're getting enough B-12 from a plant-based diet, a shake mix's 8.08-microgram added figure is the entire reason that product is a usable source, not an incidental detail. Worth being precise about scope here: of the nine dedicated "added" nutrient fields this dataset defines, only two actually carry nonzero measured values in the current Survey/FNDDS data — Vitamin B-12, added (94 ingredients) and Vitamin E, added (73 ingredients). The other seven — Calcium, Iron, Niacin, Riboflavin, Sugars, Thiamin and Vitamin C, added — exist as defined nutrient fields in this dataset's schema but carry no nonzero value on any of the 1,882 Survey ingredients currently loaded. Across all nine fields combined, 116 distinct ingredients — about 6% of this site's Survey/FNDDS coverage — carry a measured "added" value for at least one of them. The two SlimFast shake mixes used as this guide's main example are a case in point: each one carries both the 8.08-microgram Vitamin B-12, added figure cited above and a 51.92-milligram Vitamin E, added figure in the same record — a single product fortified on two of this dataset's nine tracked fields at once, both sourced to "SR Legacy."

How do I find fortified items like these myself, directly in the data?

On an ingredient detail page, scan the "Source" column for any of the nine ", added" nutrient names — Vitamin B-12, added and the other eight each have their own nutrient reference page here, and any ingredient carrying a nonzero value for one of them is, by this database's own definition, a fortified product for that nutrient. On a Foundation Food page, there's no separate "added" line to scan for outside those nine nutrients — instead, check whether the food's name itself says "with added vitamin A and vitamin D" (or similar label language) and then look at the derivation column next to the relevant nutrient to see whether that specific figure was measured or simply taken from the label.

Does a higher "added" number always mean a better data point?

No — the number and its derivation are two separate pieces of information, and this guide's examples show why that matters. The 8.3-microgram Special K20 figure and the 8.08-microgram SlimFast figure look almost identical, but one traces to "SR28" and the other to "SR Legacy" — two different historical releases, carried forward without independent reanalysis in this current dataset. Treat the added-nutrient value as a real, specific figure for that product, and treat the derivation and source columns as the separate, equally important record of how confident USDA itself is in where that figure came from.