In 1977, the FDA approved caffeine as GRAS (Generally Recognized As Safe) for use in cola-type beverages at a concentration of 0.02%.
Notes on verification
FDA regulation 21 CFR 182.1180 confirms GRAS status for caffeine in cola beverages at 0.02%, but the 1977 date reflects a reaffirmation process rather than the original 1959 listing, so 'approval' framing is slightly imprecise. [tier=bronze indep_score=0.539 clusters=2 claim_tier=notable]