FROM:
Nutr Cancer 1999; 34 (1): 56–61
Tsubono Y; Tsugane S; Gey
Epidemiology and Biostatistics Division,
National Cancer Center Research Institute East,
Kashiwa, Japan.
ytsubono@hsph.harvard.edu
To examine the geographic associations between plasma
antioxidant levels and gastric cancer risk, we conducted an
ecological study in five regions of Japan representing the
threefold variation in the disease mortality
within the country. Subjects were 634 men aged 40-49 years
sampled
randomly from the five regions with 72% response rates. Plasma
concentrations of five carotenoids (beta-carotene, alpha-
carotene,
lycopene, lutein, and zeaxanthin), alpha-tocopherol, and ascorbic
acid were measured, and the mean levels were correlated with
age-adjusted mortality rates from gastric cancer. beta-Carotene
and
alpha-tocopherol were inversely correlated with gastric cancer
rates (r = -0.31 and -0.89, respectively). alpha-Carotene and
lycopene showed stronger inverse correlation than did beta-
carotene
(r = -0.67 and - 0.56, respectively), but these relations
disappeared after the exclusion of one outlying region in Okinawa
with the lowest mortality. In contrast, ascorbic acid revealed a
negative correlation with the exclusion of this outlier (r =
-0.61). Lutein and zeaxanthin were not inversely associated with
risk. The results suggest that plasma levels of beta-carotene and
alpha-tocopherol, and possibly alpha-carotene, lycopene, and
ascorbic acid, may partly account for the regional difference in
gastric cancer mortality in Japan.