Vitamin C and human health--a review of recent data relevant
Weber P; Bendich A; Schalch W
Roche Vitamins & Fine Chemicals' Paramus' NJ 07652' USA.
Int J Vitam Nutr Res, 66(1):19-30 1996
The recent scientific literature indicates that beyond merely
protecting against scurvy vitamin C contributes to many aspects
human health. The main areas of research reviewed include: 1.
requirements of smokers. The data indicate that the vitamin C
requirement of smokers is higher by at least 60 mg per day (up
mg per day) than that of nonsmokers. 2. Important functions of
body' such as immune response' pulmonary function' and iron absorption
are related to vitamin C intakes. Daily vitamin C intake of at
150-200 mg per day enhance these functions. 3. vitamin C may
critical roles in the prevention of CHD' cancer and cataract.
the available data' vitamin C intakes of at least 80-120 mg per
associated with lowering the risk of these chronic diseases.
literature documents that these and much higher intake levels
vitamin C are safe.
vitamin C abrogates the deleterious effects of UVB radiation
cutaneous immunity by a mechanism that does not depend on TNF-alpha.
Nakamura T; Pinnell SR; Darr D; Kurimoto I; Itami S; Yoshikawa
Schepens Eye Research Institute and Department of Dermatology'
Medical School' Boston' Massachusetts 02114' U.S.A.
J Invest Dermatol, 109(1):20-4 1997 Jul
Acute low-dose treatment of murine skin with ultra violet B (UVB)
impairs induction of contact hypersensitivity (CH) to
dinitrofluorobenzene (DNFB) in certain inbred strains of mice
UVB-susceptible)' but not in others (termed UVB-resistant)' and
promotes tolerance. These deleterious effects of ultraviolet
(UVR) are mediated in part by TNF-alpha' which is released from
UVR-exposed epidermal and dermal cells. Because UVR damage to
also been ascribed in part to the generation of reactive oxygen
intermediates (ROIs) such as superoxide anion (O2-)' hydrogen
(H2O2)' hydroxyl radical (OH-)' and singlet oxygen ((1)O2)' we
investigated whether vitamin C (ascorbic acid)' which can nullify
prevents the deleterious effects of UVR on the cutaneous immune
We found that epicutaneous application of vitamin C (10% L-ascorbic
acid solution) abrogated the deleterious effects of acute low-dose
on induction of CH and prevented the induction of tolerance.
however' did not reverse the effects of TNF-alpha on CH induction
tolerance. These results indicate that (i) ROIs generated
intracutaneously by UVR contribute to the impaired ability of
skin to support the induction of CH and to promote the induction
tolerance and (ii) these effects are not dependent on TNF-alpha.
Effects of supplemental vitamins E and C on the immune responses
Hidiroglou M; Batra TR; Ivan M; Markham F
Centre for Food and Animal Research' Agriculture and Agri-Food
Ottawa' ON' Canada.
J Dairy Sci, 78(7):1578-83 1995 Jul
Two experiments were conducted to evaluate the effects of oral
supplementation of vitamin C and vitamin E (alpha-tocopherol)'
and in combination' on immune responses of calves. In Experiment
Holstein newborn female calves were supplemented with 0' 1' and
of vitamin C from birth to 6 wk of age. Concentrations of ascorbic
in blood plasma were significantly higher for supplemented calves
for control calves. No significant differences among treatments
occurred in the concentrations of IgG1' IgG2' and titer to keyhole
limpet hemocyanin. In Experiment 2' effects of oral supplementation
vitamins E and C on immune responses were studied using 18 Holstein
female calves. Concentrations of alpha-tocopherol in blood plasma
significantly higher for supplemented than for control calves.
concentrations increased from birth to wk 1' and then very little
change occurred from wk 1 to 6. Differences among treatments
concentrations of IgG1' IgG2' IgM' and titer to keyhole limpet
hemocyanin were not significant; however' concentrations of IgM
calves supplemented with vitamins E and C generally tended to
than those of control calves. Antibodies to keyhole limpet hemocyanin
were higher at 6 wk than at 4 wk of age.
Enhancement of natural killer cell activity and T and B cell
by buffered vitamin C in patients exposed to toxic chemicals:
of protein kinase-C.
Heuser G; VoJdani A
Neuromed & Neurotox Associates' Thousand Oaks' CA 91361'
Immunopharmacol Immunotoxicol, 19(3):291-312 1997 Aug
After exposure to many toxic chemicals' NK function can be decreased
significantly. Weeks or months later' natural killer (NK) function
rebound to normal levels in some and can be suppressed for prolonged
periods of time in other patients. In view of this' we decided
the effect of buffered vitamin C on NK' T and B cell function
patients who had been exposed to toxic chemicals. After the first
draw' 55 patients immediately ingested granulated buffered vitamin
water at a dosage of 60 mg/Kg body weight. Exactly 24 hours later'
blood was again drawn for a follow-up study of NK' T and B cell
function. vitamin C in high oral dose was capable of enhancing
activity up to ten-fold in 78% of patients. Lymphocyte blastogenic
responses to T and B cell mitogens were restored to the normal
after vitamin C usage. Signal transduction enzyme protein kinase
(PKC) appeared to be involved in the mechanism of induction of
activity by vitamin C. We conclude that immune functional abnormalities
can be restored after toxic chemical exposure by oral usage of
vitamin C and common cold incidence: a review of studies with
under heavy physical stress.
Hemil a H
Department of Public Health' University of Helsinki' Finland.
Int J Sports Med, 17(5):379-83 1996 Jul
Several studies have observed an increased risk of respiratory
infections in subJects doing heavy physical exercise. vitamin
been shown to affect some parts of the immune system' and accordingly
it seems biologically conceivable that it could have effects
increased incidence of respiratory infections caused by heavy
stress. In this report the results of three placebo-controlled
that have examined the effect of vitamin C supplementation on
cold incidence in subJects under acute physical stress are analyzed.
one study the subJects were school-children at a skiing camp
Swiss Alps' in another they were military troops training in
Canada' and in the third they were participants in a 90 km running
race. In each of the three studies a considerable reduction in
cold incidence in the group supplemented with vitamin C(0.6-1.0
was found. The pooled rate ratio (RR) of common cold infections
studies was 0.50 (95% CI: 0.35-0.69) in favour of vitamin C groups.
Accordingly' the results of the three studies suggest that vitamin
supplementation may be beneficial for some of the subJects doing
exercise who have problems with frequent upper respiratory infections.
vitamin C and the genesis of autoimmune disease and allergy (review).
Kodama M; Kodama T
Kodama Research Institute of Preventive Medicine' Nagoya' Japan.
In Vivo, 9(3):231-8 1995 May-Jun
The purpose of this review paper is to present relevant information
assessing the validity of our clinical investigation on the clinical
usefulness of vitamin C infusion treatment tested in the control
autoimmune disease and allergy. Firstly' we describe the historical
background of this study and then present the results of both
experimental and clinical investigations as regards the therapeutic
effect of vitamin C infusion treatment for the control of immune
disorders including diabetes mellitus. Secondly' we discuss the
interdisciplinary nature of our studies in the light of recent
in clinical vitaminology' endocrinology and immunology. Thirdly'
suggest the possibility that the use of our vitamin C infusion
treatment may be beneficial in the clinical management of AIDS'
which the immunological background data are in favor of the
participation of an autoimmune mechanism in the genesis of this
disease. Finally' we stress the importance of paradigm change
achievement of a breakthrough in natural science.
Carotenoids and antioxidant vitamins in patients after burn inJury.
Rock CL; Dechert RE; Khilnani R; Parker RS; Rodriguez JL
Department of Surgery' the University of Michigan' Ann Arbor'
J Burn Care Rehabil, 18(3):269-78; discussion 268 1997 May-Jun
Oxidative stress may contribute to secondary tissue damage and
immune function in patients after burn inJury. The purpose of
was to describe plasma antioxidant micronutrient concentrations
adult patients admitted with extensive burn inJuries (> 20
% total burn
surface area) to a level-1 trauma burn center during a 21-day
after admission. The effect of administering beta-carotene was
examined with use of a prospective randomized subJects design:
received either placebo or 30 mg/day in an enteral feeding. Plasma
concentrations of alpha- and gamma-tocopherol' carotenoids (alpha
beta-carotene' lycopene' beta-cryptoxanthin' lutein)' and retinol
measured with high- performance liquid chromatography' and vitamin
was quantified with spectrophotometry' at baseline and twice
Vitamin C' tocopherol' and retinol concentrations were low at
but levels increased significantly over the study period in both
(p < 0.05). Plasma beta-carotene concentration increased when
carotenoid was provided in the oral feeding. Otherwise' plasma
carotenoid concentrations were low at baseline and remained low
throughout the study period despite normalization of associated
Sustained levels of ascorbic acid are toxic and immunosuppressive
human T cells [see comments]
Eylar E; B]aez I; Navas J; Mercado C
Department of Biochemistry' Ponce School of Medicine' PR.
P R Health Sci J, 15(1):21-6 1996 Mar
Ascorbate (vitamin C) can protect from oxidative damage to DNA
lipids that may lead to aging' cancer' and other dysfunctions.
we find that purified human T cells deteriorate if maintained
ascorbate in culture for 18 hrs. or more; viability and Il-2
are over 90% curtailed by ascorbate at 50 micrograms/ml. T cell
proliferation and adhesion are severely suppressed at 10-25
micrograms/ml. Dihydro-ascorbate was much less toxic or suppressive.
The suppressive effect of ascorbate appears irreversible' since
of ascorbate after 18 hrs. did not restore the mitogenic response.
Although moderate dietary levels of ascorbate often reach 250-1000
or more daily and appear beneficial' our data caution against
megadoses of ascorbate for treatment of patients with AIDS and
Vitamin C' neutrophil function' and upper respiratory tract infection
risk in distance runners: the missing link.
Division of Physical Education' University of the Witwatersrand'
Johannesburg' South Africa.
Exerc Immunol Rev, 3():32-52 1997
Moderate submaximal exercise results in neutrophilia and enhanced
phagocytic and oxidative capacity of neutrophils. It has been
hypothesized' however' that during intensive exercise and periods
intensive training this pro-oxidative effect becomes suppressive.
vitamin C is widely recognized for its antioxidant function in
extracellular fluid' and it has been shown to neutralize O2-'
.OH and to attenuate the suppression of phagocytic function.
manifestation of reduced neutrophil function following participation
ultramarathon races has' however' not been observed. Although
neutrophils constitute 50-60% of leukocytes and although they
first line of defense to bacteriological invasion' postrace episodes
upper respiratory tract infection (URTI) are not correlated with
decrement in the function of this individual parameter of immune
function. The efficacy of vitamin C supplements in reducing the
incidence of postrace URTI symptoms' therefore' cannot be fully
explained at this stage.
Antioxidant vitamins affect food animal immunity and health.
Department of Animal Sciences' Washington State University' Pullman
J Nutr, 125(6 Suppl):1804S-1808S 1995 Jun
Carotenoids (beta-carotene and lycopene)' vitamin E (alpha-tocopherol)
and vitamin C (ascorbate) are naturally-occurring antioxidant
that play important roles in animal health by inactivating harmful
radicals produced through normal cellular activity and from various
stressors. Both in vitro and in vivo studies showed that these
antioxidant vitamins generally enhance different aspects of cellular
and noncellular immunity. The antioxidant function of these
micronutrients could' at least in part' enhance immunity by maintaining
the functional and structural integrity of important immune cells.
compromised immune system will result in reduced animal production
efficiency through increased susceptibility to diseases' thereby
leading to increased animal morbidity and mortality.
Exercise' immunology and upper respiratory tract infections.
Division of Physical Education' University of the Witwatersrand'
Johannesburg' South Africa.
Int J Sports Med, 18 Suppl 1():S69-77 1997 Mar
The literature reveals a paradoxical response of the immune and
defense systems to endurance exercise apparent stimulation following
long-term regular training and suppression in response to acute
exposure to exhaustive endurance exercise. Several epidemiological
surveys have confirmed a clinical manifestation of immunosuppression
the form of increased incidence of upper respiratory tract infection
symptoms following participation in competitive marathon and
ultramarathon running events. Prerace training status and racing
intensity have been related to the incidence of this symptomatology
during the postrace fortnight. Nutritional intervention studies
shown the antioxidant nutrient' vitamin C' to be effective in
the incidence of upper respiratory tract infection symptoms following
competitive distance events. Laboratory studies have revealed
vitamin to be the first line of defense in neutralizing the
auto-oxidative activity of phagocytes. It is hypothesized that
exercise-induced neuroendocrine stimulation of the oxidative
neutrophils increases the rate of release of reactive oxygen
and that these are' in turn' neutralized by high plasma ascorbate
levels. Enhancing intrinsic antioxidant defense by increasing
antioxidant intake is thus theorized to be of long-term benefit
serious endurance athletes engaged in heavy training and competition.
Nutritional modification of inflammatory diseases.
Schoenherr WD; Jewell DE
Mark Morris Institute' Topeka' KS' USA.
Semin Vet Med Surg (Small Anim), 12(3):212-22 1997 Aug
Regulation of the immune system is extremely complex. We are
starting to understand how the immune system coordinates the
response to a disease or invading pathogen. Immunomodulation'
term implies' can be used to designate either a suppression or
augmentation of an immune response. Suppressing the function
immune system may be important in cases of inflammation and augmenting
the immune response when increased resistance to disease is required.
Nutrition does and can play an important role in modulation of
animal`s immune system. The maJority of scientific literature
on the interaction of nutrition and the immune system correlates
effects of nutrient deficiency and modulation of an immune response.
These studies have evaluated deficiencies of protein; energy;
soluble vitamins A' D' and E; the B-complex vitamins; vitamin
the minerals selenium' iron' zinc' and copper and their relationship
immune dysfunction. Most recently' researchers have concentrated
efforts on evaluating the impact specific fatty acids have on
modulation of the immune system. Undoubtedly' the nutritional
the animal plays an important role in resistance mechanisms against
disease causing organisms and may influence the outcome of disease
infected animals. The focus of this chapter is to concentrate
role specific polyunsaturated fatty acids have on the immune
of animals and to consider the potential for nutritional modification
of diseases related to inflammation.