Carrageenan: Food Additive or Health Concern? A Comprehensive Review.

BACKGROUND: Carrageenan, a sulfated polysaccharide extracted from red seaweeds, is widely used in the food, pharmaceutical, and cosmetic industries due to its gelling, thickening, and stabilizing properties. SUMMARY: Its widespread use in the Western diet and processed foods has raised scientific interest regarding its health effects. Evidence remains contradictory: some studies report antioxidant, antiviral, antitumor, and immunomodulatory benefits, whereas others suggest potential adverse outcomes, including impaired glucose metabolism, intestinal inflammation, and immune dysregulation. These effects appear to depend on carrageenan type, molecular weight, purity, dosage, and host-related factors. Regulatory bodies such as the FDA and EFSA generally consider carrageenan safe, although concerns remain regarding infant formulas and long-term exposure. KEY MESSAGES: Carrageenan cannot be uniformly classified as beneficial or harmful. Its biological effects are context-specific, and further well-designed clinical and mechanistic studies are needed to clarify dose-response relationships, safety in vulnerable populations, and implications for industry and public health nutrition.