nutrition labels for protein bars
Protein bars live and die on their numbers — protein up, sugar down — and those exact numbers are what the label has to defend. Here's the serving size the FDA expects, the claims you're allowed to print, and the allergen traps in a typical bar.
key takeaways
- The serving size is 40 g (one bar) — the reference amount for cereal/granola bars.
- "High protein" needs ≥ 10 g per serving on a digestibility-corrected %DV basis; "good source" needs 5–9.9 g.
- Milk, soy, peanuts and tree nuts are the usual allergens — declare each by specific name.
- "Low sugar" has no FDA definition; use "no added sugars" (if true) or state the grams.
- Sugar alcohols still count as carbohydrate even when they don't count as sugar.
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The short version
A protein bar is a marketing document as much as a snack: the whole pitch is on the front of the wrapper, and the Nutrition Facts panel on the back has to substantiate it. Get the serving size, protein declaration and claim thresholds right and the label sells for you; get them wrong and you've made an unenforceable claim on a federally regulated package.
Serving size — the part people get wrong
Reference amount: 40 g (typically 1 bar). The reference amount for grain-based bars and cereal/granola bars is 40 g, so a single bar is almost always one serving. If your bar is much larger (60–70 g), it's still one serving as long as it's clearly a single-eat item — but your calories and sugar scale up with it, which matters for the claims below.
Allergens you have to declare
Protein bars are allergen-dense by design. Whey and milk protein isolates mean milk; soy protein and soy lecithin mean soy; peanut and almond butters and inclusions mean peanuts and tree nuts; and many use wheat- or barley-derived ingredients. Declare each by specific name ("almonds," not "tree nuts") in the ingredient list or a Contains statement — this is the single most-audited part of a bar label.
The Nutrillius generator auto-detects the Big-9 allergens from your ingredient list and writes the Contains statement for you — useful even if you only need the ingredient list.
Claims you can (and can’t) make
Every nutrient-content claim on the package has a legal threshold the panel must back up. For protein bars, the ones that come up most:
- High in protein / Excellent source — protein must be ≥ 20% DV (10 g) per serving.
- Good source of protein — protein 10–19% DV (5–9.9 g) per serving.
- Good source of fiber — fiber ≥ 10% DV (2.8 g) per serving.
- Low sugar — there is no FDA definition for "low sugar" — avoid it; use "reduced sugar" (≥25% less than a reference) or state the gram amount.
- No added sugars — requires 0 g added sugars AND no sugar-containing ingredient added in processing.
The builder shows which claims your recipe already qualifies for as you tweak it — see the rounding rules for how the declared numbers behind those thresholds are set.
A sample protein bars label
Almond Cocoa Protein Bar
INGREDIENTS: Soy protein isolate, almonds, dates, chicory root fiber, cocoa, whey protein isolate, almond butter, sea salt.
Contains: Soy, Almonds, Milk.
Serving size 1 bar (50g)
Note the three allergens surfaced from just eight ingredients — soy (isolate), almonds (nut + butter), and milk (whey). A protein bar rarely has fewer than two.
Where protein bars makers slip up
Protein quality can lower your declared %DV
The FDA lets you declare protein as a simple gram amount, but the % Daily Value for protein must be corrected for digestibility (PDCAAS). Many bars skip the %DV entirely (which is allowed) precisely to avoid the correction — but then you cannot make a "high protein" claim, which legally depends on the corrected %DV. If you want the claim, you need the corrected number.
Sugar alcohols aren't sugar — but they are carbs
Erythritol, maltitol and allulose let bars post low "sugar" numbers, but they still count in Total Carbohydrate and can be declared as Sugar Alcohol on a separate line. Don't quietly drop them from carbs to make the net-carb math look better on-pack — the panel has to reconcile.
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Build your protein bars label
Enter your recipe and get a print-ready FDA Nutrition Facts panel, ingredient statement and allergen declaration — with the 40 g (typically 1 bar) serving handled for you. Free to build; pay only when you download.
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frequently asked questions
What serving size should a protein bar use?
One bar, based on the 40 g reference amount (RACC) for cereal and granola bars. Even a 50–60 g bar is a single serving if it's clearly meant to be eaten in one sitting — but your per-serving calories, sugar and protein all scale with the actual bar weight, which affects your claims.
Can I say my bar is 'high protein'?
Only if it delivers ≥ 20% of the Daily Value for protein (10 g) per serving, measured on a digestibility-corrected (PDCAAS) basis. Because that correction can pull plant-protein numbers down, some bars that show '15 g protein' still don't legally qualify for the claim. If you want to print it, run the corrected %DV.
Do I have to declare sugar alcohols on a protein bar?
You must include them in Total Carbohydrate, and you may declare them on a voluntary 'Sugar Alcohol' line. If you make any claim about sugar alcohols (like 'sugar free' driven by them), the Sugar Alcohol line becomes mandatory.
Is a protein bar a food or a dietary supplement?
Almost always a conventional food, so it uses the Nutrition Facts panel — not Supplement Facts. A bar only crosses into supplement territory if it's marketed as a dietary supplement (dosed actives, supplement positioning), which is unusual for bars sold as snacks.
sources & references
Written from the primary regulation. We link the actual rule so you can verify every serving size, threshold and requirement at the source.
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