The antioxidant activity of saliva has been investigated in 28 apparen
tly healthy individuals and seven dental patients with periodontal dis
ease. The results show that the major aqueous antioxidant component of
whole saliva is uric acid, with lesser contributions from ascorbic ac
id and albumin. All are present at lower concentrations than those fou
nd in the plasma water. The total antioxidant activity (TAA) of saliva
correlates (r(2) = 0.972) with the concentration of uric acid, which
contributes more than 70% of the TAA. Stimulation of salivary flow is
associated with increased production of antioxidants. The antioxidant
potential of saliva does not appear to be compromised in patients with
periodontal disease but this may relate to the antioxidant flow from
the gingival crevicular fluid.