title: Reduced intake of dietary antioxidants can impair antioxidant status in type 2 diabetes patients.
abstract: BACKGROUND
  Oxidative stress plays a major role in the pathogenesis of type 2 diabetes.
  
  
  OBJECTIVE
  The objective of this study was to investigate associations between dietary intake of antioxidants and antioxidant status in patients with type 2 diabetes.
  
  
  METHODS
  In 80 patients with type 2 diabetes and 37 controls, total antioxidant status (TAS), activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD), malondialdehyde (MDA), and 4‑hydroxyalkenals (4‑HAE) were measured. The 24‑hour food recall method and our own dietary database were used to calculate dietary total antioxidant capacity (DTAC), polyphenol content (DTPC), and flavonoid content (DTFC). Dietary antioxidant vitamins were calculated using national food composition databases.
  
  
  RESULTS
  Serum TAS was 1.57 mmol/l in controls, 1.41 mmol/l in patients with newly diagnosed type 2 diabetes, and 1.23 mmol/l in patients with long-standing type 2 diabetes. Serum MDA and 4‑HAE levels were 0.78 μmol/l in controls, 1.45 μmol/l in newly diagnosed diabetes, and 1.74 μmol/l in long-standing diabetes. GPx and SOD activities were 42.6 and 1340 units/g hemoglobin (Hb), respectively, in controls, 47.3 and 2373 units/g Hb in long-standing diabetes, and 58.2 and 3093 units/g Hb in newly diagnosed diabetes. DTAC, DTPC, DTFC, and vitamin C content were 5697 μmol Trolox equivalents (TE), 1031 mg gallic acid equivalents (GAE), 223 mg quercetine equivalents (QE), and 82 mg, respectively, in control diet. In patients with long-standing diabetes, the values were 4271 μmol TE, 822 mg GAE, 173 mg QE, and 63 mg, respectively, and in those with newly diagnosed type 2 diabetes, they were 4545 μmol TE, 839 mg GAE, 180 mg QE, and 65 mg, respectively.
  
  
  CONCLUSIONS
  The diet of type 2 diabetes patients is poor in antioxidants despite increased demand.
authors.forename: Małgorzata E
authors.initials: ME
authors.lastname: Zujko
authors.forename: Anna M
authors.initials: AM
authors.lastname: Witkowska
authors.forename: Maria
authors.initials: M
authors.lastname: Górska
authors.forename: Juliusz
authors.initials: J
authors.lastname: Wilk
authors.forename: Adam
authors.initials: A
authors.lastname: Krętowski
mesh_terms: D000328:Adult; D000368:Aged; D000975:Antioxidants / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D005260:Female; D005979:Glutathione Peroxidase / Q000378:metabolism*; D006801:Humans; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism*; D008875:Middle Aged; D018384:Oxidative Stress / Q000502:physiology*; D011044:Poland; D013482:Superoxide Dismutase / Q000378:metabolism*; D013997:Time Factors; D014815:Vitamins / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D014815:Vitamins; D008315:Malondialdehyde; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase