Effects of three-month oral supplementation of beta-carotene and vitamin C on serum concentrations of carotenoids and vitamins in middle-aged subjects: a pilot study for a randomized controlled trial to prevent gastric cancer in high-risk Japanese population.
Prior to a randomized controlled trial to prevent gastric cancer by oral supplementation of beta-carotene and vitamin C in a high-risk Japanese population, we examined the serum response to three-month oral supplementation of beta-carotene (0, 3, 30 mg / day) and vitamin C (0, 50, 1000 mg / day) by a three-by-three factorial design using 54 subjects (age range = 40 - 69 years). Serum concentrations of carotenoids, alpha-tocopherol, and ascorbic acid were examined at baseline, and one, two, and three-month points. Both serum beta-carotene and ascorbic acid were significantly higher in high-dose groups than in each placebo group during the supplementation. The serum beta-carotene increased gradually (597 - 830% increase) during the study, whereas the serum ascorbic acid reached nearly a steady-state at the one-month point and remained stable thereafter (88 - 95% increase). No statistically significant interaction between beta-carotene and vitamin C supplementations was observed either for serum beta-carotene or for serum ascorbic acid. Among carotenoids and alpha-tocopherol examined, serum lycopene in the high-dose beta-carotene group was significantly higher than in the placebo group at all points. No unfavorable change in carotenoids and alpha-tocopherol was observed in any group.
Sasaki
S
S
Epidemiology and Biostatistics Division, National Cancer Center Research Institute East, 6-5-1 Kashiwanoha, Kashiwa 277-8577, Japan. stssasak@east.ncc.go.jp.
Tsubono
Y
Y
Okubo
S
S
Hayashi
M
M
Kakizoe
T
T
Tsugane
S
S
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001205:Ascorbic Acid / Q000008:administration & dosage* / Q000097:blood; D005260:Female; D005757:Gastritis, Atrophic / Q000097:blood / Q000628:therapy*; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D012044:Regression Analysis; D013274:Stomach Neoplasms / Q000517:prevention & control*; D013997:Time Factors; D014810:Vitamin E / Q000097:blood; D019207:beta Carotene / Q000008:administration & dosage* / Q000097:blood
D019207:beta Carotene; D014810:Vitamin E; D001205:Ascorbic Acid