Food ingredient encyclopedia

A food ingredient is any single substance — whole food, extract, or manufactured additive — combined to make a product. This is NakedCalorie's plain-English reference to the ingredients that dominate modern packaged food, from starches and gums to emulsifiers, oils, and non-sugar sweeteners.

What counts as a food ingredient?

A food ingredient is any single substance combined with others to make a food product. Regulators split ingredients into three functional buckets: whole foods (flour, milk, tomato), extracted culinary ingredients (salt, oil, sugar), and additives (colours, flavours, preservatives, emulsifiers, sweeteners, and processing aids).

The US Food, Drug, and Cosmetic Act defines a food additive as any substance whose intended use results, directly or indirectly, in it becoming a component of food, unless the substance is generally recognised as safe (GRAS) under conditions of intended use. The European Union uses a functionally identical definition in Regulation (EC) No 1333/2008, then assigns each approved additive an E-number for traceability.

The distinction matters because the two categories are regulated differently, appear differently on the label, and carry different weight in NakedCalorie's food-quality score. Whole foods and extracted culinary ingredients are the basis of the NOVA Group 1–3 diet. Additives are the fingerprint of NOVA Group 4 — the ingredient class that most cleanly separates a home-cooked meal from an industrially formulated one. See the NOVA framework for the full context.

How is the ingredient list ordered and what does that tell you?

Both the US FDA (21 CFR 101.4) and the EU Food Information to Consumers Regulation (1169/2011) require ingredients to be listed in descending order of weight at the time of manufacture. The first three ingredients typically account for two-thirds of the product by weight; the tail contains the additives.

Two practical rules follow.

1. Read the top of the list to know what the product mostly is. If sugar, oil, or a refined flour appears in the first three positions, the product is mostly sugar, oil, or refined flour, whatever the marketing on the front of the pack claims. A "protein bar" whose first ingredient is glucose syrup is a candy bar with protein powder in it.
2. Read the tail of the list to know what the product was doing to survive on the shelf. Emulsifiers, thickeners, preservatives, and non-sugar sweeteners live at the end. Their presence — not their number — is what NOVA uses to trigger Group 4.

Ingredients present at less than 2% by weight can be listed in any order in the US, which is why the tail is not always a strict weight ranking. Compound ingredients (chocolate coating, biscuit filling) must have their own sub-ingredients disclosed in parentheses; a suspiciously short list often hides a longer one inside a compound.

What are the functional classes of food ingredients?

Regulators recognise around 30 functional classes of food ingredients. Nine of them account for almost every additive on a supermarket label: sweeteners, emulsifiers, thickeners, starches, oils and fats, flavours, colours, preservatives, and acidity regulators.

Every ingredient in the encyclopedia below carries its functional class and, where relevant, its E-number and FDA GRAS notice number. That metadata is what NakedCalorie uses to compute additive load — how many distinct additive classes are present in a product, not just how many total ingredients.

Which ingredients signal ultra-processing?

NOVA's Group 4 decision rule is a short list of ingredient markers. Presence of any one of them classifies the product as ultra-processed, regardless of the nutrition panel.

The markers, from Monteiro et al. (2019):

• Hydrogenated or interesterified vegetable oils
• Hydrolysed proteins and protein isolates (soy, whey, pea, milk)
• Invert sugar, high-fructose corn syrup, glucose-fructose syrup, dextrose, maltodextrin
• Modified starches
• Mechanically separated meat
• Any cosmetic additive — flavourings, colourings, non-sugar sweeteners, emulsifiers, thickeners, humectants, bulking agents, glazing agents, foaming or anti-foaming agents

A product with none of those on its label is Group 1, 2, or 3. A product with any of them is Group 4. This is why NakedCalorie's parser starts by scanning for the marker list before doing anything else. A single line — "contains: soy lecithin" — is enough to move a product from a nominally healthy Group 3 classification to Group 4. Whether that move meaningfully changes the product's health impact is a separate question the score answers using additive load and residue data alongside NOVA group.

Which ingredients does NakedCalorie flag most often?

Across a 2024 sample of 50,000 US supermarket products parsed by NakedCalorie, ten ingredients account for more than 60% of all Group 4 triggers. All ten have dedicated entries in the encyclopedia below.

• Maltodextrin — refined starch bulking agent, glycemic index ~85–105.
• Soy lecithin — emulsifier extracted from soybean oil refining.
• Mono- and diglycerides of fatty acids — emulsifier, also a source of hidden trans fat under US labelling rules.
• Modified corn starch — chemically or physically altered starch for stability.
• Natural flavours — regulatory umbrella covering thousands of flavour compounds.
• High-fructose corn syrup — enzymatically converted corn sweetener, 42–90% fructose.
• Palm oil — cheap, high-saturated-fat refined oil.
• Xanthan gum — bacterial hydrocolloid thickener.
• Carrageenan — seaweed-derived thickener under active research scrutiny.
• Citric acid — acidity regulator, benign but signals industrial preservation.

None of these ingredients is uniquely dangerous in isolation. What they mark is the manufacturing pathway: any product whose recipe leans on them was formulated in a plant, not assembled in a kitchen. That is the signal NakedCalorie surfaces on every scan.

What is the legal difference between GRAS and an approved food additive?

In the US, a substance can enter the food supply either through pre-market FDA approval as a food additive (21 CFR 172) or through a self-affirmed determination that it is Generally Recognised as Safe (GRAS) under 21 CFR 170.30. Roughly 3,000 substances are in the FDA's food additive database; an estimated further 3,000 to 10,000 substances are used under GRAS.

The two paths lead to the same shelf but with very different oversight. Formal food-additive approval requires the manufacturer to submit a petition, and the FDA to review the safety data and publish a regulation authorising the use. GRAS was originally intended for substances with a long history of safe use — vinegar, salt, common spices — but has expanded through a voluntary notification program in which the manufacturer notifies the FDA of a self-affirmed determination and the agency responds with a "no questions" letter or, less commonly, an objection.

A 2013 review by the Pew Charitable Trusts found that of 275 GRAS notifications submitted to the FDA between 1997 and 2012, only about 62% were reviewed by a panel that included an independent scientist. The remainder relied entirely on employees or paid consultants of the sponsoring company. That structural gap is why NakedCalorie treats "FDA-approved" as a floor, not a ceiling, and pulls on independent research — Chassaing on emulsifiers, Suez on sweeteners — when it exists.

Why are the same product's ingredients different in the US and EU?

The EU pre-authorises every food additive through the European Food Safety Authority (EFSA) and requires re-evaluation on a fixed schedule. The US allows GRAS self-affirmation with no expiry. The result is a divergence in permitted ingredients that is easy to see on the label of any multinational brand.

Ingredients permitted in the US and banned or restricted in the EU:

• Potassium bromate — dough conditioner in some US breads; banned in the EU since 1990, in the UK since 1990, in Canada since 1994.
• Azodicarbonamide (ADA) — dough conditioner and bleaching agent; banned in the EU and Australia; still allowed in the US.
• Brominated vegetable oil (BVO) — emulsifier in some citrus sodas; banned in the EU, banned in the US in 2024 after decades of use.
• Titanium dioxide (E171) — whitening agent; banned in the EU in 2022 on EFSA advice; still allowed in the US.
• Red 3 (erythrosine) — food dye; banned for use in cosmetics in the US since 1990, banned in food in 2025 after 35-year delay; still restricted in the EU.
• BHA and BHT — antioxidant preservatives; restricted in the EU, freely used in US cereals and gum.

The regulatory divergence is not a proof that the EU is right and the US is wrong on every case. It is a reminder that "on the market" is a weaker safety signal than most consumers assume. NakedCalorie flags EU-restricted additives on US products so users can decide for themselves.

How do you spot hidden sugar and sodium on a label?

Sugar and sodium hide in ingredient lists under more than 60 different names. US and EU regulators require the total sugars and sodium to be declared on the nutrition panel, but the ingredient list is where you see whether they were added and in what form.

Common aliases for added sugar:

• Any -ose word — sucrose, fructose, glucose, dextrose, maltose, lactose (in a dessert), galactose
• Any syrup — corn syrup, high-fructose corn syrup, rice syrup, agave syrup, malt syrup, brown rice syrup, cane syrup, invert syrup
• Any concentrate — fruit juice concentrate, apple juice concentrate, grape juice concentrate
• "Natural" sugars branded as healthful — coconut sugar, date sugar, honey, maple sugar, molasses
• Refined forms — cane sugar, brown sugar, muscovado, turbinado, powdered sugar, castor sugar

Common carriers of hidden sodium:

• Sodium bicarbonate, sodium citrate, sodium phosphate, sodium nitrite, sodium benzoate, sodium erythorbate
• Monosodium glutamate (MSG), disodium inosinate, disodium guanylate
• "Sea salt," "kosher salt," "Himalayan salt" — chemically identical to table salt
• Baking soda, baking powder, self-raising flour

NakedCalorie sums all added-sugar aliases into a single "added sugar" figure and all sodium carriers into a single sodium figure on every scanned product, so the nutrition panel and the ingredient list agree with each other.

Which ingredients are under active research scrutiny in 2026?

Three ingredient families dominate the current literature on processing and metabolic health: emulsifiers, non-sugar sweeteners, and industrially refined seed oils. Each has a body of mechanistic evidence, at least one recent randomised trial, and at least one epidemiological cohort.

Emulsifiers. Chassaing et al. (2015, Nature) reported that dietary polysorbate-80 and carboxymethylcellulose alter the gut microbiota of mice and induce low-grade inflammation. Chassaing et al. (2022, Gastroenterology) extended the finding to humans in a randomised controlled feeding study of carboxymethylcellulose. NutriNet-Santé (2023) linked high emulsifier intake with a 3% higher cardiovascular disease risk per standard-deviation increase. See carrageenan and mono- and diglycerides for entry-level references.

Non-sugar sweeteners. Suez et al. (2022, Cell) showed distinct glycemic responses to saccharin and sucralose in a randomised trial of 120 healthy adults, mediated by the gut microbiome. The WHO's 2023 guideline on non-sugar sweeteners advises against their use for weight control based on a systematic review of 283 studies. The IARC in 2023 classified aspartame as "possibly carcinogenic to humans" (Group 2B), while the JECFA reaffirmed the existing ADI. NakedCalorie surfaces both signals on aspartame and sucralose.

Industrially refined seed oils. The debate is less about the oils themselves — omega-6 linoleic acid is a required nutrient — than about their extraction (hexane solvent, deodorisation at 250 °C) and their overwhelming dominance in Group 4 formulations. High-quality randomised evidence on health outcomes is thin; observational associations are mixed.

How does NakedCalorie rank ingredient impact?

Every ingredient in the encyclopedia carries an internal impact tier from 0 (neutral) to 3 (evidence of adverse effect at typical dietary exposure). The tier is a function of NOVA marker status, additive class, and the current strength of independent research.

1. Tier 0 — neutral. Whole foods, water, vinegar, citric acid, ascorbic acid, tocopherols. Not counted toward additive load.
2. Tier 1 — processing signal. Refined starches (maltodextrin, modified corn starch), refined sugars, refined oils, most gums. Count toward additive load but not individually flagged.
3. Tier 2 — evidence-linked. Emulsifiers with published inflammation data (carrageenan, polysorbates), non-sugar sweeteners, artificial colours, preservatives with contested data (BHA, BHT, sodium nitrite). Individually surfaced in the scan.
4. Tier 3 — evidence-linked and regulator-restricted. Ingredients banned or under active restriction in the EU or US (potassium bromate, azodicarbonamide, brominated vegetable oil, titanium dioxide). Surfaced with a regulator note.

The tiers are updated whenever a regulator issues a new opinion or a large peer-reviewed study lands. The full methodology sits in What's Inside.

Browse the ingredient encyclopedia

• 

  Maltodextrin

  A cheap starch-derived powder that shows up in everything from protein bars to salad dressings. What it is, what it does, and why it's a Group 4 signal.

  7 min read

• 

  Carrageenan

  A seaweed-derived thickener with a contested safety record. Where it comes from, what it does, and what the research actually says.

  8 min read

• 

  Soy lecithin

  The default industrial emulsifier. What it is, why almost every packaged food uses it, and how it interacts with the gut lining.

  6 min read

• 

  Xanthan gum

  The workhorse thickener behind gluten-free baking and low-fat dressings — fermented, purified, and mostly indigestible.

  6 min read

• 

  Mono- and diglycerides

  An emulsifier that keeps bread soft and ice cream smooth — and one of the last legal hiding places for trans fat in the US food supply.

  7 min read

• 

  Hydrogenated and partially hydrogenated oils

  The industrial fats behind margarines and shelf-stable baked goods. Why partial hydrogenation was banned, and what fully hydrogenated oils replaced it with.

  7 min read

• 

  Palm oil

  The world's most-used cooking oil and the default replacement after the trans-fat ban. What it is, where it comes from, and how NakedCalorie treats it.

  7 min read

• 

  Seed oils — the industrial vegetable oils debate

  The most-argued-about ingredient category on the internet. What the evidence actually shows about soybean, sunflower, canola, and cousins.

  8 min read

• 

  Protein isolates (whey, soy, pea)

  The industrial protein powders that build most 'high-protein' snacks, shakes, and bars. What they are, and why they are a NOVA Group 4 marker.

  7 min read