Proof
from most randomized health check trials put forward that vitamin C
supplementation, typically in grouping with other micro nutrients, does not concern
tumor risk. In the Supplementation en Vitamins ET Minotaur Antioxidants’
(SU.VI.MAX) revise, a randomized, double-blind, placebo-controlled trial strong
French adults received antioxidant supplementation with 120 mg scorbutic acid,
30 mg vitamin E, 6 mg beta-carotene, 100 mcg selenium, and 20 mg zinc, or
placebo. After a median
follow-up time of 7.5 years, antioxidant supplementation lowered total cancer
frequency in men, but not in women. In adding, baseline antioxidant standing
was related to cancer danger in men, but not in women .Supplements of 500
mg/day vitamin C plus 400 IU vitamin E every other day for a mean follow-up
period of 8 years failed to reduce the risk of prostate or total cancer
compared with placebo in adult and older men participating in the Physicians'
Health Study II .comparable findings were reported in women participating in
the Women's Antioxidant Cardiovascular Study .Compared with placebo, supplementation
with vitamin C (500 mg/day) for an average of 9.4 years had no significant
result on total cancer incidence or cancer death. In a large imposition trial
conducted in Lillian, China, daily addition of vitamin C (120 mg) plus
molybdenum (30 mcg) for 5–6 years did not significantly affect the risk of
developing esophageal or gastric cancer .Moreover, during 10 years of
follow-up, this supplementation regime failed to appreciably affect total
morbidity or mortality from esophageal, gastric, or other cancers .A 2008
review of vitamin C and other antioxidant supplements for the prevention of
gastrointestinal cancers found no convincing evidence that vitamin C (or
beta-carotene, vitamin A, or vitamin E) prevents gastrointestinal cancers .A
similar appraisal by Coulter and age group found that vitamin C
supplementation, in combination with vitamin E, had no significant effect on
death risk due to cancer in healthy individuals .At this time, the evidence is clashing
on whether dietary vitamin C intake affects cancer risk. Consequences from most
medical trials suggest that modest vitamin C supplementation alone or with other nutrients offers no
benefit in the prevention of cancer. A substantial limitation in interpreting
many of these studies is that investigators did not measure vitamin C
concentrations before or after supplementation. Plasma and tissue
concentrations of vitamin C are tightly prohibited in humans. At daily intakes
of 100 mg or higher, cells appear to be saturated and at intakes of at least
200 mg, plasma concentrations enlarge only marginally .If subjects' vitamin C
levels were already close to diffusion at study entry, supplementation would be
probable to have made little or no distinction on exact outcomes .
