FD&C Yellow No. 5 / FD&C Blue No. 1

FD&C Yellow No. 5 (also known as Tartrazine) and FD&C Blue No. 1 (also known as Brilliant Blue FCF) are synthetic food dyes. They are manufactured through chemical synthesis, typically derived from petroleum.

These dyes are added to foods and beverages to impart color. Yellow No. 5 provides a yellow hue, while Blue No. 1 provides a blue hue; they can also be combined to create other colors. They are frequently found in candies, baked goods, beverages, and dessert toppings.

Both FD&C Yellow No. 5 and FD&C Blue No. 1 are FDA-approved color additives for use in food. In April 2025, the FDA announced a plan to phase out petroleum-based synthetic dyes, which includes Yellow No. 5 and Blue No. 1. JECFA has evaluated both dyes and set an acceptable daily intake. EFSA has also evaluated these dyes and set an acceptable daily intake. FD&C Yellow No. 5 has been associated with allergic-type reactions, such as hives or asthma, in a small number of sensitive individuals. There have been concerns regarding a potential link between synthetic food dyes, including Yellow No. 5 and Blue No. 1, and hyperactivity in some children; however, the evidence for this link is mixed, with some studies suggesting a connection and others not finding consistent evidence. The FDA acknowledges that some children may be sensitive to these dyes but states that current scientific evidence does not show a causal link between them and hyperactivity in the general population.