Sodium Aluminum Phosphate vs Caramel Color IV: which is worse?

What is Sodium Aluminum Phosphate?

Sodium aluminum phosphate (SALP) is a leavening acid and food additive used in baked goods, particularly self-rising flour and baking powder. It provides a slow, sustained leavening action during baking. SALP is also used as an emulsifying salt in processed cheese products.

What is Caramel Color IV?

Caramel Color IV (Class IV caramel, E150d) is a food coloring made by heating sugar with both ammonium and sulfite compounds. This production method creates a unique set of reactive byproducts, notably 4-methylimidazole (4-MEI), which has been linked to cancer in animal studies. It is the most widely used caramel coloring in beverages like Coca-Cola and Pepsi.

Documented risks

Sodium Aluminum Phosphate: The primary health concern with SALP is aluminum exposure. Dietary aluminum intake has been studied in relation to neurotoxicity, and there is ongoing scientific debate about whether chronic dietary aluminum exposure contributes to Alzheimer's disease risk. EFSA's 2008 review of dietary aluminum exposure concluded that the tolerable weekly intake (TWI) was being exceeded by some European populations based on total dietary aluminum sources, raising concern. A 2011 EFSA risk assessment noted that certain high-aluminum sources (including baked goods from SALP-containing leavening agents) contributed meaningfully to total dietary aluminum. The WHO has set a PTWI (provisional tolerable weekly intake) of 2 mg/kg body weight/week for total aluminum. However, the causal link between dietary aluminum from food-grade SALP and Alzheimer's disease has not been definitively established in human studies.

Caramel Color IV: The primary concern with Caramel Color IV is 4-methylimidazole (4-MEI), a byproduct of the ammonia-sulfite caramel production process. The National Toxicology Program (NTP) found that 4-MEI caused lung cancer in male and female mice at high doses in 2-year bioassay studies, leading to California listing 4-MEI as a known carcinogen under Proposition 65 in 2011. The Prop 65 safe harbor level is 29 micrograms 4-MEI per day (the level that would cause 1 additional cancer per 100,000 people over a 70-year lifetime). CSPI testing in 2011-2012 found Coca-Cola and Pepsi sold in California contained 4-MEI levels that, at typical consumption rates, would exceed this threshold — triggering voluntary reformulation by both companies to reduce 4-MEI in their US products. The FDA reviewed 4-MEI and concluded that typical exposure levels 'are not a safety concern.' EFSA's evaluation found the NTP findings concerning but noted the margin of safety at typical European exposure levels. The cancer mechanism in mice involves high doses that may not extrapolate to typical human cola consumption.