The Good Fiber Company · Data tracker
Decode your fiber supplement
What the additives, sweeteners, fillers and colours on a fiber-supplement label actually are, and why they are there. Every entry is sourced to EFSA opinions and EU regulation.
Data current as of July 2026 · reviewed annually
A flavoured fiber powder can carry a dozen of these, and not one of them is fiber. Intense sweeteners to mask the taste, colours purely for looks, anti-caking agents for the factory. Here is what each one is, so you can read any label.
25
additives commonly found on fiber-supplement labels
9
carry a mandatory EU warning label
1
banned as an EU food additive since 2022
Group
E951 Aspartame
Intense sweetener
Masks the taste of plain fiber.
EFSA ADI 40 mg/kg/day
Worth knowing IARC classed it “possibly carcinogenic” (Group 2B) in 2023; EFSA and JECFA left the ADI unchanged.
E950 Acesulfame K
Intense sweetener
Intense sweetener, often paired with aspartame or sucralose.
EFSA ADI 15 mg/kg/day
EFSA raised the ADI to 15 mg/kg in 2025 (from 9).
E955 Sucralose
Intense sweetener
Intense sweetener, heat-stable, common in powders.
EFSA ADI 15 mg/kg/day
EFSA confirmed it safe at current uses but flagged uncertainty when heated above ~120 °C.
E954 Saccharin
Intense sweetener
One of the oldest intense sweeteners.
EFSA ADI 9 mg/kg/day
EFSA re-evaluated it in 2024 and set the ADI at 9 mg/kg.
E960 Steviol glycosides
Intense sweetener
Plant-derived (“stevia”), but still an intense sweetener.
EFSA ADI 4 mg/kg/day
ADI 4 mg/kg expressed as steviol equivalents (EFSA).
E420 Sorbitol
Sugar-alcohol (polyol)
Sweetens and adds bulk.
EFSA ADI Not specified
Warning label Laxative effect above ~50 g/day; foods with over 10% added polyols must carry a laxative warning.
E967 Xylitol
Sugar-alcohol (polyol)
Sweetens and adds bulk.
EFSA ADI Not specified
Warning label Same laxative-warning rule as other polyols above 10%.
E965 Maltitol
Sugar-alcohol (polyol)
Sweetens and adds bulk.
EFSA ADI Not specified
Warning label Same laxative-warning rule as other polyols above 10%.
E968 Erythritol
Sugar-alcohol (polyol)
Sweetens and adds bulk.
EFSA ADI Not specified
Generally better tolerated than other polyols; EFSA re-evaluated it in 2023.
E171 Titanium dioxide
Colour
A white colourant, purely for appearance.
EFSA ADI None
Banned Banned as an EU food additive since 2022 after EFSA (2021) could not rule out genotoxicity and set no ADI.
E102 Tartrazine
Colour
A synthetic colour, for appearance.
EFSA ADI See note
Warning label One of six colours that must legally carry “may have an adverse effect on activity and attention in children”.
E104 Quinoline Yellow
Colour
A synthetic colour, for appearance.
EFSA ADI See note
Warning label Carries the same EU child-attention warning label.
E110 Sunset Yellow FCF
Colour
A synthetic colour, for appearance.
EFSA ADI See note
Warning label Carries the same EU child-attention warning label.
E122 Carmoisine (Azorubine)
Colour
A synthetic colour, for appearance.
EFSA ADI See note
Warning label Carries the same EU child-attention warning label.
E124 Ponceau 4R
Colour
A synthetic colour, for appearance.
EFSA ADI See note
Warning label Carries the same EU child-attention warning label.
E129 Allura Red AC
Colour
A synthetic colour, for appearance.
EFSA ADI See note
Warning label Carries the same EU child-attention warning label.
E551 Silicon dioxide
Anti-caking / flow agent
Stops powder from clumping.
EFSA ADI Not specified
EFSA (2018) found no toxicity at reported uses but could not derive a numerical ADI.
E470b Magnesium salts of fatty acids
Anti-caking / flow agent
Lubricant / flow agent, common in capsules and tablets (“magnesium stearate”).
EFSA ADI Not specified
EFSA (2018) saw no safety concern and no need for a numerical ADI.
E460(i) Microcrystalline cellulose
Anti-caking / flow agent
Bulking, anti-caking and tableting aid.
EFSA ADI Not specified
EFSA (2018) concluded no numerical ADI was needed for the cellulose group.
E415 Xanthan gum
Thickener
Thickens for a smoother texture.
EFSA ADI Not specified
EFSA (2020) set no numerical ADI and saw no safety concern.
E330 Citric acid
Acidity regulator
Adds tartness and drives effervescence.
EFSA ADI Not specified
ADI “not specified”: a substance of very low concern at food-use levels.
E211 Sodium benzoate
Preservative
Preservative, mainly in liquids and gummies.
EFSA ADI 5 mg/kg/day
EFSA ADI 5 mg/kg.
E202 Potassium sorbate
Preservative
Preservative, mainly in liquids and gummies.
EFSA ADI 11 mg/kg/day
Group ADI 11 mg/kg, expressed as sorbic acid.
no E Maltodextrin
Bulking / carrier
Cheap bulking agent and carrier; adds volume and rapidly-digested carbohydrate, not fiber.
EFSA ADI Not an additive
Worth knowing A processed starch, not a numbered additive, so it is easy to miss on a label.
no E Flavourings
Bulking / carrier
Make an unpalatable powder drinkable.
EFSA ADI Not disclosed
Worth knowing Declared collectively as “flavourings”; the individual substances need not be named on the label.
Cite this dataset
The Good Fiber Company (2026). Decode your fiber supplement. https://goodfibercompany.com/decode-fiber-supplement/ Methodology
Each entry gives the additive’s E-number, its functional class, its EFSA acceptable daily intake (ADI) or safety status, any mandatory EU label warning, and why it tends to appear in a fiber supplement. Every value traces to an EFSA scientific opinion or to EU regulation, listed below. An ADI is a food-wide figure for the substance, not a statement about any product. “Not specified” is a favourable outcome the regulator assigns to substances of very low concern at food-use levels, not “unassessed”.
This catalogs additives commonly found in the category across powders, effervescents, gummies and capsules; it is not a claim that any given product contains any of them. It is a tool to decode a label, not medical advice. Reviewed annually against the latest EFSA re-evaluations; last updated in July 2026.
Sources
- Regulation (EC) No 1333/2008 of the European Parliament and of the Council on food additives (functional classes; Annex II authorised additives and E-numbers; Annex V colour warning). link
- Commission Regulation (EU) 2022/63 amending Annexes II and III to Regulation (EC) No 1333/2008 as regards the food additive titanium dioxide (E 171). link
- EFSA FAF Panel (2021). Safety assessment of titanium dioxide (E171) as a food additive. EFSA Journal 2021;19(5):6585. link
- EFSA ANS Panel (2013). Scientific Opinion on the re-evaluation of aspartame (E 951) as a food additive. EFSA Journal 2013;11(12):3496. link
- IARC Monographs Volume 134 (2023) and WHO/JECFA (14 July 2023): aspartame classified Group 2B; JECFA reaffirmed ADI 40 mg/kg bw/day. link
- EFSA sweetener re-evaluations: acesulfame K (E 950), EFSA Journal 2025 (ADI 15 mg/kg); sucralose (E 955), 2026 (ADI 15 mg/kg); saccharins (E 954), EFSA Journal 2024;22(11):9044 (ADI 9 mg/kg); steviol glycosides (E 960), EFSA Journal 2010;8(4):1537 (ADI 4 mg/kg as steviol equivalents). link
- Regulation (EU) No 1169/2011 on the provision of food information to consumers (Annex III: laxative-effect statement for >10% added polyols; collective ‘flavourings’ declaration). link
- EFSA re-evaluations of structural additives: silicon dioxide (E 551) EFSA Journal 2018;16(1):5088; salts of fatty acids (E 470a/b) 2018; celluloses incl. E 460 2018; xanthan gum (E 415) 2020; citric acid (E 330); sorbic acid/potassium sorbate (E 200/E 202); benzoic acid/sodium benzoate (E 210/E 211). link