A vegetable/fruit concentrate with high antioxidant capacity has no effect on biomarkers of antioxidant status in male smokers.
The potential benefits of a high fruit and vegetable intake on the antioxidant status and on relevant biomarkers of oxidative damage to lipids, proteins and DNA and on (functional) markers of oxidative stress were evaluated. A randomized, free living, open placebo-controlled cross-over trial of 3 wk, with a 2-wk washout period between treatments, was performed in a group of 22 male smokers with a relatively low vegetable and fruit intake using a vegetable burger and fruit drink. The vegetable burger and fruit drink increased serum levels of vitamin C, alpha-carotene, beta-carotene, beta-cryptoxanthin and zeaxanthin and plasma total antioxidant capacity. However, no effects were demonstrated on any marker of oxidative damage to lipids (malondialdehyde F(2)-isoprostane) proteins (carbonyls) and DNA (Comet assay) and (functional) markers of oxidative stress (reduced/oxidized glutathione ratio, glutathione-S-transferase alpha, glutathione-S-transferase pi and nuclear transcription factor-kappaB). Apparently, these increased levels of antioxidants in serum were not sufficiently high to show beneficial changes with the selected biomarkers. Alternatively, oxidative stress in male smokers with a relatively low fruit and vegetable intake might have been still too low to demonstrate a beneficial effect of antioxidants.
van den Berg
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R
TNO Nutrition and Food Research, 3700 AJ Zeist, the Netherlands. R.vandenBerg@voeding.tno.nl
van Vliet
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Broekmans
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Cnubben
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Vaes
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Roza
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Haenen
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GR
Bast
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van den Berg
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D000328:Adult; D000975:Antioxidants / Q000008:administration & dosage*; D001794:Blood Pressure; D001835:Body Weight; D002338:Carotenoids / Q000097:blood; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D018592:Cross-Over Studies; D004249:DNA Damage; D005638:Fruit; D006801:Humans; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D009000:Monocytes / Q000648:ultrastructure; D018384:Oxidative Stress; D012907:Smoking / Q000503:physiopathology*; D013997:Time Factors; D014280:Triglycerides / Q000097:blood; D014675:Vegetables; D014801:Vitamin A / Q000097:blood; D014810:Vitamin E / Q000097:blood
D000975:Antioxidants; D008076:Cholesterol, HDL; D014280:Triglycerides; D014801:Vitamin A; D014810:Vitamin E; D002338:Carotenoids; D008315:Malondialdehyde; D002784:Cholesterol