Vegetables and fruits both have a lot more nitrate than nitrite, and the amount of nitrite is about the same in both kinds of food.

Measures and compares nitrate and nitrite concentrations in a representative sample of vegetables and fruits from multiple sources, using standardized lab testing, to confirm the stated levels (438.31 mg/kg and 44.02 mg/kg) and assess relative similarity of nitrite levels between groups.

Synthesizes published data from multiple studies measuring nitrate and nitrite in vegetables and fruits to determine if the reported levels and relative similarity hold across diverse datasets.

Tracks nitrate and nitrite levels in commonly consumed vegetables and fruits over time to confirm consistency of the reported differences and similarity.

Compares nitrate and nitrite levels in vegetables and fruits that are known to have high vs. low levels to validate the claim’s relative differences.

Confirms the accuracy of the specific numerical values (438.31 mg/kg and 44.02 mg/kg) using controlled lab conditions.