Common Ingredients That Confuse Vegans

Some ingredients sound plant-based but can come from animal sources. Natural flavours, mono- and diglycerides (E471), unspecified lecithin, glycerin, and refined sugar are the ones vegans ask about most, because the label alone rarely settles the question.

For each ingredient below: why it is uncertain, what labels sometimes clarify, and how to decide whether to eat a product that contains it.

Why labels name the substance, not the source

Food labels name the substance, not its origin. "Lecithin" is lecithin whether it comes from soybeans or egg yolks. "Glycerin" is glycerin whether from coconut oil or tallow. Regulators approve additives based on their function and safety, not whether they are plant- or animal-derived.

That gap between what the label tells you and what you need to know as a vegan is where every ingredient in this guide sits.

Natural flavours

"Natural flavours" and "natural flavouring" are among the most common uncertain ingredients. Under US FDA rules, natural flavours are derived from plant or animal sources through physical or fermentation processes. Castoreum (from beaver anal glands) is a documented but rare example; more commonly, meat or dairy extracts flavour savoury products.

Manufacturers treat flavour formulas as trade secrets and rarely disclose sources. A vegetable soup could contain chicken-derived natural flavour. A strawberry sweet could use plant-only flavours. The label looks the same either way.

Vegan certification requires plant-derived natural flavours. For uncertified products, contact the manufacturer if the product is a staple in your diet.

Mono- and diglycerides (E471)

E471 emulsifies fat and water in bread, margarine, ice cream, and baked goods. It is made by reacting fatty acids with glycerol, and those fatty acids can come from palm oil, rapeseed, soy, or animal fat.

E471 appears on a huge number of supermarket products. Most commercial production uses vegetable sources because they are cheaper, but animal fat is permitted and not declared.

Vegan-certified products are the clearest fix. Brands like many supermarket own-label breads confirm plant-only E471 on request. See our E471 page for details.

Lecithin (E322)

Lecithin is a fat emulsifier found in chocolate, margarine, baked goods, and supplements. Soy lecithin and sunflower lecithin, the most common forms, are vegan. Egg lecithin exists but is less common in processed food.

When a label says "soy lecithin" or "sunflower lecithin," you are fine. When it just says "lecithin" or "E322" without qualification, the source is technically unknown, though soy is the default in most products.

Glycerin and glycerol

Glycerin (also called glycerol) is a sweet, syrupy alcohol used in foods, toothpaste, and cosmetics. Vegetable glycerin from coconut or soy is vegan and widely used. Unspecified "glycerin" on a non-certified product could theoretically come from animal fat, though plant sources dominate in food manufacturing.

Cosmetics are a separate concern. Glycerin in skincare is less predictable. For food, most vegans accept unspecified glycerin unless they are strict about source verification.

Sugar

Sugar itself contains no animal products, but some cane sugar is refined using bone char, charred animal bones used as a filter to whiten the crystals. Beet sugar is never processed with bone char. Organic cane sugar is also bone-char-free by certification rules.

This is a processing issue, not an ingredient issue. Many vegans eat conventional sugar; others avoid it. See our full Is Sugar Vegan? guide.

Vitamin D3

Vitamin D3 (cholecalciferol) in fortified foods is usually derived from lanolin, a wax from sheep's wool. Vitamin D2 (ergocalciferol) is plant-derived. Cereals, plant milks, and spreads often fortify with D3 without specifying the source.

Look for D2 on the label, or choose products that state "vegan vitamin D" or "lichen-derived D3."

Stearic acid and stearates

Stearic acid is a saturated fatty acid used as a lubricant and stabiliser. In food, it is usually derived from plant oils (palm, coconut), but animal sources are possible. Magnesium stearate in supplements follows the same pattern.

Most vegans consider stearic acid in food acceptable unless they require strict source verification.

Castoreum and other rare animal flavours

Castoreum, extracted from beaver castor sacs, is approved as a natural flavouring in the US and EU. It has a vanilla-raspberry profile and appears in some luxury fragrances and occasionally in food. It is rare in mainstream products but illustrates why "natural" does not mean "plant."

Where the uncertainty sits

How to decide for yourself

There is no single correct approach. Vegans draw their own lines based on how strictly they want to avoid uncertain sources.

A practical approach avoids definite animal ingredients (gelatin, milk, honey, carmine) and accepts common uncertain ones (soy lecithin, vegetable glycerin) unless the label suggests otherwise. A certification approach means buying processed foods with a vegan mark when the list contains natural flavours, E471, or unspecified lecithin. A strict approach means contacting manufacturers for every uncertain ingredient, avoiding conventional cane sugar, and skipping any product with unspecified natural flavours.

All three are valid. Consistency matters more than which level you choose.

What labels sometimes clarify

Some brands go beyond minimum legal requirements: "soy lecithin" instead of just "lecithin," "vegetable glycerin" instead of "glycerin," "plant-based natural flavours" on vegan-labelled products, "organic sugar" (bone-char-free by organic standards), and "vitamin D2" or "vegan vitamin D3 from lichen."

When a brand specifies the plant source, trust it. When they do not, use the tools and approaches above.

Reading order on labels

Ingredients are listed by weight, highest first. If milk, egg, or gelatin appears in the first three ingredients, the product is clearly not vegan. Ambiguous ingredients like natural flavours or E471 lower down may matter less to some vegans but still warrant checking if you eat the product daily.

Allergen bolding (EU/UK) and "Contains:" statements (US) help spot milk and egg quickly, but they will not flag carmine, gelatin, or shellac, none of which are major allergens.

Palmitic acid and palm oil derivatives

Palmitic acid and its salts can come from palm oil or animal fat. In practice, palm oil is the dominant commercial source because it is cheap and abundant. Strict vegans who avoid palm oil for environmental reasons face a separate issue from vegan status: palm-derived palmitic acid is still plant-based.

Enzymes listed without source

"Enzymes" on a bread or cheese label may refer to fungal or bacterial enzymes (vegan) or animal-derived lipase and rennet (not vegan). Without specification, treat as uncertain. Sourdough and traditional bread methods often avoid added enzymes entirely.

Alcohol and fermentation

Some fermented products use animal-derived fining agents even when the core ingredients are plant-based. Miso, soy sauce, and vinegar are usually vegan, but flavoured versions may contain fish sauce, honey, or dairy. Read the flavoured variant's label, not the plain product you assume it matches.

For E-number-specific confusion, see our E-number guide and animal-derived additives reference. Paste any confusing ingredient list into our Animal Ingredient Detector to flag uncertain and non-vegan items.