title: Biological effects of fruit and vegetables.
abstract: A strong and persistent effect of plant-derived foods on the prevention of lifestyle diseases has emerged from observational studies. Several groups of constituents in plants have been identified as potentially health promoting in animal studies, including cholesterol-lowering factors, antioxidants, enzyme inducers, apoptosis inducers etc. In human intervention studies the dose levels achieved tend to be lower than the levels found to be effective in animals and sampling from target organs is often not possible. A controlled dietary human intervention study was performed with forty-three volunteers, providing 600 g fruit and vegetables/d or in the controls a carbohydrate-rich drink to balance energy intake. Surrogate markers of oxidative damage to DNA, protein and lipids, enzymic defence and lipid metabolism were determined in blood and urine. It was found that a high intake of fruit and vegetables tends to increase the stability of lipids towards oxidative damage. Markers of oxidative enzymes indicate a steady increase in glutathione peroxidase (GPX1) activity in erythrocytes during intervention with fruit and vegetables but there is no effect on GPX1 transcription levels in leucocytes. No change occurs in glutathione-conjugating or -reducing enzyme activities in erythrocytes or plasma, and there are no effects on the transcription of genes involved in phase 2 enzyme induction or DNA repair in leucocytes. Fruit and vegetable intake decreases the level of total cholesterol and LDL-cholesterol, but does not affect sex hormones. In conclusion, it has been shown that total cholesterol and LDL-cholesterol, markers of peripheral lipid oxidation, and erythrocyte GPX1 activity are affected by high intakes of fruit and vegetables. This finding provides support for a protective role of dietary fruit and vegetables against CVD.
authors.affiliation: Danish Institute for Food and Veterinary Research, Soborg, Denmark. lod@dfvf.dk
authors.forename: Lars O
authors.initials: LO
authors.lastname: Dragsted
authors.forename: Britta
authors.initials: B
authors.lastname: Krath
authors.forename: Gitte
authors.initials: G
authors.lastname: Ravn-Haren
authors.forename: Ulla B
authors.initials: UB
authors.lastname: Vogel
authors.forename: Anne Marie
authors.initials: AM
authors.lastname: Vinggaard
authors.forename: Per
authors.initials: P
authors.lastname: Bo Jensen
authors.forename: Steffen
authors.initials: S
authors.lastname: Loft
authors.forename: Salka E
authors.initials: SE
authors.lastname: Rasmussen
authors.forename: The late BrittMarie
authors.initials: Tl
authors.lastname: Sandstrom
authors.forename: Anette
authors.initials: A
authors.lastname: Pedersen
mesh_terms: D000328:Adult; D008078:Cholesterol, LDL / Q000097:blood / Q000378:metabolism; D004249:DNA Damage; D004790:Enzyme Induction; D005260:Female; D005638:Fruit; D015870:Gene Expression; D005979:Glutathione Peroxidase / Q000378:metabolism*; D006801:Humans; D050356:Lipid Metabolism / Q000502:physiology*; D015227:Lipid Peroxidation / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress; D014675:Vegetables; D000094765:Glutathione Peroxidase GPX1
chemical_list: D008078:Cholesterol, LDL; D005979:Glutathione Peroxidase; D000094765:Glutathione Peroxidase GPX1