Beta-Carotene vs Riboflavin: which is worse?

What is Beta-Carotene?

Beta-carotene is an orange pigment found abundantly in carrots, sweet potatoes, and leafy greens. As a food additive (E160a), it is used as a coloring agent providing yellow to orange hues. It also functions as a precursor to vitamin A in the body. Commercial beta-carotene used as a food additive can be extracted from algae (Dunaliella salina) or produced synthetically.

What is Riboflavin?

Riboflavin (vitamin B2) is an essential water-soluble vitamin used as a yellow food colorant (E101). It naturally occurs in meat, fish, dairy, eggs, and leafy greens. Commercial riboflavin for food use is produced by bacterial fermentation (primarily using Ashbya gossypii or Bacillus subtilis). It provides a yellow-to-green-yellow color in foods.

Documented risks

Beta-Carotene: Beta-carotene from food is considered safe and beneficial. However, high-dose beta-carotene supplements (25 mg/day and above) were associated with increased lung cancer risk in two major clinical trials — ATBC (1994) and CARET (1996) — specifically in heavy smokers and asbestos-exposed workers. Food-level exposure from coloring use is far below supplemental doses. Harmless skin yellowing (carotenemia) can occur with very high dietary intake. As a food additive colorant, no significant safety concerns exist.

Riboflavin: Riboflavin is one of the safest food additives. It is an essential nutrient with no established upper tolerable intake limit due to its extremely low toxicity — excess riboflavin is simply excreted in urine (which turns bright yellow). No carcinogenicity, teratogenicity, or mutagenicity has been identified.