Authors
Pool-Zobel BL. Bub A. Muller H. Wollowski I. Rechkemmer G.
Institution
Institute of Nutritional Physiology, Federal Research Centre for Nutrition,
Karlsruhe, Germany.
Title
Consumption of vegetables reduces genetic damage in humans: first results of
a human intervention trial with carotenoid-rich foods.
Source
Carcinogenesis. 18(9):1847-50, 1997 Sep.
Abstract
A human intervention study with vegetable products has been performed in
twenty three healthy, non smoking males aged 27-40. It was the aim of the
study to assess whether consumption of vegetables containing different
carotenoids could protect against DNA damage and oxidative DNA damage. The
subjects consumed their normal diets, but abstained from vegetables high in
carotenoids throughout the study period. After a 2 week depletion period,
they received daily 330 ml tomato juice
with 40 mg lycopene (weeks 3 and 4), 330 ml carrot juice
with 22.3 mg beta-carotene and 15.7 mg alpha-carotene (weeks 5 and 6), and 10
g dried spinach powder (in water or milk) with 11.3 mg lutein (weeks 7 and
8). Blood was collected weekly and DNA damage was detected in peripheral
blood lymphocytes with the 'COMET' assay. Oxidised DNA bases were detected by
including an incubation step with endonuclease III. The supplementation of
the diet with tomato, carrot or spinach products resulted in
a significant decrease in endogenous levels of strand breaks in lymphocyte
DNA. Oxidative base damage was significantly reduced during the carrot
juice intervention. These findings support the hypothesis
that carotenoid containing plant products exert a cancer-protective effect
via a decrease in oxidative and other damage to DNA in humans.