The 15 Most Common Food Additives — What Each One Actually Does

Preservative

Used in acidic beverages (sodas, juices) to inhibit yeast and mold growth. When combined with ascorbic acid (vitamin C) in the same product, it can form benzene — a known carcinogen — at trace levels. A 2007 Southampton University study also linked it to hyperactivity in children when combined with certain food dyes.

Preservative

A salt of sorbic acid, potassium sorbate inhibits mold and yeast in cheese, wine, yogurt, and dried fruit. It is among the most extensively studied food preservatives. EFSA and FDA both consider it safe at current use levels. Some rare contact allergy cases have been documented.

Acidulant / Preservative

Produced by bacterial fermentation, lactic acid is the compound responsible for the tang in yogurt, sauerkraut, and sourdough. Used commercially to extend shelf life and control pH. FDA GRAS. Naturally occurring in the human body as a metabolic byproduct; no concerns at food-use levels.

Antioxidant / Vitamin C

Naturally found in citrus fruit, ascorbic acid is used to prevent browning and extend shelf life. It is also a mandatory co-additive in cured meats to reduce nitrosamine formation. FDA GRAS. No adverse effects at typical food-use levels.

Antioxidant / Preservative

BHA prevents fat oxidation in snack foods, cereals, and butter. It is listed as a possible human carcinogen by IARC (Group 2B) based on animal studies showing tumor formation at high doses. The US National Toxicology Program classifies it as 'reasonably anticipated to be a human carcinogen.' Still FDA GRAS — a status that has drawn criticism from public health researchers.

Antioxidant / Preservative

Often used alongside BHA, BHT extends the shelf life of fats and oils in packaging materials and cereals. Evidence for carcinogenicity is less clear than with BHA — some animal studies show tumor promotion, others suggest anticarcinogenic effects. FDA GRAS. EFSA permits use at low levels. Classified as a possible endocrine disruptor in some independent reviews.

Thickener / Stabilizer

A polysaccharide produced by fermenting Xanthomonas campestris bacteria on glucose. It thickens salad dressings, sauces, and gluten-free baked goods. FDA GRAS. Well-tolerated in most people; very high doses can cause digestive discomfort in sensitive individuals.

Emulsifier

Extracted from soybean oil as a byproduct of processing, soy lecithin keeps chocolate from separating and improves texture in baked goods. Most soy proteins — the allergenic fraction — are removed during extraction; residual protein levels are generally too low to trigger reactions in soy-allergic individuals, though severe allergy warrants caution.

Thickener / Gelling Agent

Extracted from red seaweed, carrageenan is used in dairy products, infant formula, and processed meats. Undegraded carrageenan (food-grade) is approved by FDA, but some studies on degraded carrageenan (poligeenan) show inflammatory effects in animal models. IARC classified poligeenan as possibly carcinogenic (Group 2B). The debate about whether food-grade carrageenan poses any human risk remains active in the literature.

Acidulant / Preservative / Flavor

One of the most widely used food additives globally, citric acid acidifies beverages, preserves canned foods, and enhances tart flavors. Produced commercially by fermenting Aspergillus niger mold on sugar substrates. FDA GRAS. Well-tolerated except in rare mold-sensitive individuals.

Bulking Agent / Carrier

A highly processed starch derivative with a glycemic index higher than table sugar, maltodextrin is used to bulk out powdered foods, instant sauces, and sports supplements. It contributes to caloric density without sweetness. No acute safety concerns, but research links high-GI diets to metabolic risk — relevant for diabetics and prediabetics.

Sweetener

HFCS is produced by enzymatically converting corn starch glucose to fructose. It is nutritionally similar to sucrose but metabolized differently — fructose bypasses insulin regulation and is processed primarily in the liver. High intake is associated with non-alcoholic fatty liver disease (NAFLD), dyslipidemia, and insulin resistance in clinical studies, though causation is debated. FDA GRAS.

Artificial Sweetener

Aspartame is approximately 200 times sweeter than sugar and is used in diet beverages, tabletop sweeteners, and reduced-sugar foods. In July 2023, the WHO's IARC classified it as a possible carcinogen (Group 2B), based on limited evidence from observational studies. The same month, JECFA (WHO/FAO) maintained the ADI at 40 mg/kg/day, stating the evidence was insufficient to change safety limits. Individuals with phenylketonuria (PKU) must avoid it entirely.

Flavor Enhancer (Umami)

MSG enhances savory taste by stimulating glutamate receptors. It occurs naturally in tomatoes, parmesan, and soy sauce. FDA classifies it as GRAS. Double-blind studies have not confirmed the anecdotal 'Chinese Restaurant Syndrome.' EFSA set an ADI of 30 mg/kg/day in 2017 and noted that typical dietary exposure is below this threshold for most adults.

Synthetic Food Dye

One of the most widely used synthetic dyes in US food, Red 40 colors candies, cereals, beverages, and maraschino cherries. The 2007 Southampton study linked it (in a mix with other dyes and sodium benzoate) to increased hyperactivity in children. The EU requires a warning label on products containing it. The FDA reviewed the evidence in 2011 and did not mandate a label change, concluding the data was not sufficient to establish causation.