Xanthan Gum vs Yellow Dye 6: which is worse?

What is Xanthan Gum?

Xanthan gum is a polysaccharide produced by fermentation of sugars by the bacterium Xanthomonas campestris. It is a white to off-white powder that dissolves in cold or hot water to form a viscous gel. It is widely used as a thickener and stabilizer and is a key ingredient in gluten-free baking.

What is Yellow Dye 6?

Yellow Dye 6 (Sunset Yellow FCF) is a synthetic orange-yellow azo dye derived from petroleum. It produces a bright orange-yellow color and is structurally similar to Yellow 5 but produces a more orange shade. Its chemical formula is C16H10N2Na2O7S2.

Documented risks

Xanthan Gum: Generally recognized as safe by both FDA and EFSA. At high doses, xanthan gum can have laxative effects due to its fermentable fiber content, producing gas and bloating in some individuals. A 2011 case report in the journal Pediatrics raised concerns about xanthan gum in infant formula (as 'Simply Thick') being associated with necrotizing enterocolitis; the FDA subsequently advised against its use in premature infants. For healthy adults consuming normal food amounts, it poses no significant health risk.

Yellow Dye 6: Yellow Dye 6 was included in the 2007 Lancet study (McCann et al.), which found that a mixture of six dyes including Yellow 6 and sodium benzoate significantly increased hyperactivity in children. EFSA confirmed the effect warranted mandatory warning labels in the EU. EFSA's 2009 re-evaluation examined animal carcinogenicity data and found some studies showing adrenal tumors in male mice at high doses. EFSA set an ADI of 2.5 mg/kg body weight — lower than Yellow 5's ADI of 7.5 mg/kg, reflecting greater concern. The review noted limitations in the available data. Impurity concerns: commercial batches of Yellow 6 have been found to contain aromatic amine impurities including benzidine and 4-aminobiphenyl — both IARC Group 1 human carcinogens. A 1992 CSPI analysis documented these impurities, citing them as reason for concern. A 2007 study in Toxicological Sciences found Yellow 6 altered zinc and iron biomarker levels in rat blood at high doses, raising mineral metabolism concerns. Human relevance at typical exposure is unclear. Hypersensitivity reactions including urticaria, rhinitis, and contact dermatitis are documented. Cross-reactivity with aspirin is reported similarly to Yellow 5. In April 2025, the FDA announced plans to phase out Yellow 6 with other petroleum-based dyes.