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PubMed2003

Vitamins A, and C and folate status in Mexican children under 12 years and women 12-49 years: a probabilistic national survey.

OBJECTIVE: To describe the epidemiology of Vitamin A and C and folic acid deficiencies and their association with sociodemographic and dietary factors in a national probabilistic sample of Mexican women and children. MATERIAL AND METHODS: This is a probabilistic sample from the National Nutrition Survey 1999 (ENN-99) including 1,966 children and 920 women. Vitamins A and C were measured in serum by high-performance liquid chromatography, and folic acid in total blood by a microbiological method. Determinants for such deficiencies were explored by multiple regression models. RESULTS: Vitamin A deficiency (retinol < 10 micrograms/dl) was rare in both children and women. But subclinical deficiency (retinol > 10 and < 20 micrograms/dl) was present in 25% of children. The likelihood of subclinical deficiency of vitamin A was less in older children (OR = 0.98, p = 0.01) and in women with higher body mass index (OR = 0.93, p = 0.01). About 30% of children < 2 years of age and 40% of women were vitamin C deficient. The likelihood of vitamin C deficiency was less in children and women as socioeconomic level increased (OR = 0.69, p = 0.03, and OR = 0.80, p = 0.04), and higher in older women (OR = 1.02, p = 0.05). The prevalence of folate deficiency varied in children (2.3 to 11.2), in women it was 5%. Folate deficiency was less in children of higher socioeconomic level (OR = 0.62, p = 0.01), and in those eating more vegetables (OR = 0.22, p = 0.01). CONCLUSIONS: The high prevalence of subclinical deficiency of vitamin A in children is indicative of risk of further deterioration under adverse circumstances. Vitamin C deficiency in both children and women implies in addition diminished ability for iron absorption. The English version of this paper is available too at: http://www.insp.mx/salud/index.html.

Adolescent↗
PubMed1998

Vitamin C status of an outpatient population.

OBJECTIVE: To determined the prevalence of vitamin C deficiency (plasma vitamin C concentrations less than 11.4 mumol/L) and vitamin C depletion (plasma vitamin C concentrations from 11.4 to less than 28.4 mumol/L) in an outpatient population. SUBJECTS AND METHODS: A consecutive sample of patients presenting at a health maintenance organization laboratory for outpatient procedures was utilized. Plasma vitamin C concentrations were determined in 350 females and 144 males, aged 6 to 92 years (mean +/- SD: 46.7 +/- 18.7 years). RESULTS: The mean plasma vitamin C concentration for all subjects was 32.4 +/- 13.6 mumol/L. Mean plasma vitamin C did not vary by sex, race, or fasted state. Diabetics had a significantly lower mean plasma vitamin C concentration (25.6 +/- 10.8 mumol/L) compared to patients presenting for general check-up/gynecological exams (33.5 +/- 14.8 mumol/L) or pregnancy exams (32.4 +/- 9.7 mumol/L). Six percent of subjects had plasma vitamin C concentrations indicative of vitamin C deficiency (n = 31), and 30.4% of the sample were vitamin C depleted (n = 150). The prevalence of vitamin C deficiency or vitamin C depletion did not differ by race or visit category. CONCLUSIONS: Surprisingly high rates of vitamin C deficiency and vitamin C depletion were evident among generally healthy, middle class patients visiting a health care facility for routine health exams, gynecological exams, and pregnancy exams.

Adolescent↗
PubMedDate not supplied

Vitamin C status of elderly patients on admission into an assessment geriatric ward.

A study of the plasma vitamin C concentration in patients in an assessment geriatric ward was carried out for 1 year. The incidence of vitamin C deficiency, as reflected by the plasma vitamin C level was 40.1%. There was almost no difference in its prevalence amongst the sexes or various age groups, but the incidence of vitamin C deficiency was highest in patients admitted from institutions. Furthermore, this study also revealed that patients with certain illnesses were more vulnerable to vitamin C deficiency than other patients and the standard hospital diet alone was not sufficient to improve the vitamin C status of these patients in the short-term.

Administration, Oral↗
PubMed1985

Pathogenetic factors of aging macular degeneration.

In order to explore the pathogenetic factors of aging macular degeneration, risk factors from epidemiologic studies and causative factors from clinical and laboratory studies were reviewed. From the epidemiologic studies, the risk factors of senile macular degeneration included: personal characteristics such as age, sex, race, height, family history, and strength of hand grip; ocular characteristics such as hyperopia, color of iris and senile cataract; and systemic diseases and environmental exposure such as cardiovascular diseases, smoking, lung infections, and chemical exposures. The causative factors suggested from clinical and laboratory studies include: drusen, choroidal vascular diseases, photic injury, and vitamin C deficiency. It is postulated that aging macular degeneration is a multifactorial syndrome. Different etiologic factors may inflict damaging effect on the macula, resulting in a common set of clinical manifestations that are interpreted as aging macular degeneration.

Aged↗
PubMed1999

Dietary antioxidants and magnesium in type 1 brittle asthma: a case control study.

BACKGROUND: Type 1 brittle asthma is a rare form of asthma. Atopy, psychosocial factors and diet may contribute to this condition. As increased dietary magnesium has a beneficial effect on lung function and selenium, vitamins A, C and E have antioxidant properties, a study was undertaken to test the hypothesis that patients with brittle asthma have diets deficient in these nutrients compared with subjects with non-brittle asthma and healthy adults. METHODS: A case control study of the dietary intakes of 20 subjects with brittle asthma, 20 with non-brittle asthma, and 20 healthy adults was performed using five day weighed dietary records. Intake of magnesium was the primary outcome measure with selenium and vitamins A, C and E as secondary outcomes. Serum levels were measured at the same time as the dietary assessment. RESULTS: Sixty subjects (27 men) of mean age 49.5 years were recruited and completed the study. Subjects with brittle asthma had statistically lower median dietary intakes of vitamins A and E than the other groups (vitamin A: brittle asthma 522.5 micrograms/day, non-brittle asthma 869.5 micrograms/day, healthy adults 806.5 micrograms/day; vitamin E: brittle asthma 4.3 mg/day, non-brittle asthma 4.6 mg/day, healthy adults 4.5 mg/day). Median dietary intakes for the other nutrients were not significantly different between groups. Serum levels were within normal ranges for each nutrient in all subjects. Intakes less than the reference nutrient intake (RNI) for magnesium and vitamins A and C, and less than the safe intake (SI) for vitamin E were more likely in patients with brittle asthma than in those with non-brittle asthma. CONCLUSION: Nutrient deficiency and reduced antioxidant activity may contribute to disease activity in type 1 brittle asthma, although a prospective study of replacement therapy will be needed to confirm this hypothesis.

Ascorbic Acid Deficiency↗
PubMed1984

Cell-mediated immunity in nutritional deficiency.

Dietary deficiencies of specific nutrients profoundly alter cell-mediated immune responses in man and experimental animals. Both moderate and severe deficiencies are associated with significant changes in immunocompetence. Diets with inadequate levels of protein, calories, vitamin A, pyridoxine, biotin and zinc result in loss of thymic cellularity. Secondary to thymic atrophy, the production of thymic hormones critical for the differentiation of T lymphocytes is reduced, especially in protein-calorie malnutrition and zinc deficiency. Confirmation of a T cell maturational defect in nutritional deprivation comes from the observations of decreased total (T3 and rosette-forming) T cells in the peripheral blood of children with kwashiorkor and marasmus, with preferential loss of helper/inducer (T4) T cell subsets. Reduced number and in vitro function of T cells have also been reported in experimental deficiencies of iron, zinc, copper, and vitamins A and E. Loss of cutaneous hypersensitivity to mitogens and antigens is a consistent sequela of dietary deficiencies of protein, vitamins A and C, pyridoxine, iron and zinc. Cell-mediated immunity directed against allogeneic histocompatibility antigens (e.g. mixed leukocyte cultures, graft versus host, skin graft rejection) may actually be enhanced by experimental protein and polyunsaturated fat deficiencies. Alternatively, pyridoxine, ascorbate and biotin deficiencies resulted in delayed rejection of skin allografts. Cytotoxic T lymphocyte (CTL) activity is impaired in zinc-, iron- and copper-deficient mice, as well as in scorbutic guinea pigs. Natural killer (NK) cell function may be either enhanced or depressed, depending upon the nutrient and its effects on interferon production. Several authors have demonstrated normal or enhanced macrophage activity in a variety of experimental deficiencies. The extrapolation of these observations to infectious disease resistance is not straightforward, and depends upon the nature of the microbe, its own nutrient needs, and the relative importance of innate, as opposed to immunologic, defense mechanisms.

Animals↗
PubMed1979

Vitamin C deficiency in growing willow ptarmigan (Lagopus lagopus lagopus).

Willow ptarmigan chicks raised on a diet containing 265 mg ascorbic acid/kg develop scury-like symptoms and die by 4 weeks of age. If blueberry plants are given as an ad libitum supplement to this diet, the malady is prevented. We have described the clinical, pathological and histological changes which accompany this malnutrition and conclude that they are in accord with the description of scurvy in guinea pig and man. Biochemical determination of ascorbic acid synthesis in the kidney of ptarmigan chicks indicated a rate of synthesis five times that found in livers of growing white rats. Blueberry plants and many other plants found in the natural diet of ptarmigan chicks contain 2,000 to 5,000 mg ascorbic acid/kg dry weight. Feeding experiments showed that the pathological signs were avoided and that already afflicted chicks recovered if the vitamin C content of the diet was raised to 750 mg/kg dry weight of food. Since the food intake of the chicks was 5 to 8 g/day the daily requirement of external vitamin C is about 150 mg/kg body weight. To our knowledge this is the first example of an animal which, while producing vitamin C itself, requires substantial amounts of external vitamin C to survive.

Animals↗
PubMed2006

[To 20-years anniversary of Chernobyl catastrophe: an attempt to study the vitamin, calcium, iron and selenium status of children and adult population in Slavutich and to correct elicited deficiencies].

The article concisely illustrates the vitamin and mineral state of population of town of Slavutich, including personal of Chernobyl Nuclear Power Station, children of pre-school age and pregnancy women, studied in 1992. Vitamins and minerals deficiency in the main of C and B vitamins and selenium was revealed in all the studied groups. Appropriate measures were developed and introduced to eliminate the detected dusturbances; but however some unsolved problems remained. Taking into account the forthcoming 20th anniversary of Chernobyl disarter, the authors of the come back to considering the obtained data in hope to atlract attention of medical scientific and public to the remained unsolved problems of micronutrient deficiency.

Adult↗
PubMedDate not supplied

[Changes in the activity of antioxidant enzymes in an experimental peroxidation syndrome in the rabbit].

Activity of the antioxidant enzymes under conditions of experimental syndrome of peroxidation was studied in rabbits maintained at a diet deprived of antioxidants. Peroxidation of lipids was increased in the animals; at the same time, content of the vitamin-antioxidants was decreased in their tissues. Activity of the antioxidant enzymes was distinctly increased within the first steps of the experiment after which it was decreased. The data obtained suggest that deficiency of the vitamin-antioxidants may be transitory compensated by an increase in activity of the antioxidant enzymes; long-term deprivation of bioantioxidants led, however, to inhibition of biosynthesis of the antioxidant enzymes.

Animals↗
PubMed2006

Vitamin C neglect in hemodialysis: sailing between Scylla and Charybdis.

In our efforts to meet the vitamin C requirements of dialysis patients we confront a medical dilemma--do we allow the patient to become depleted of vitamin C, with the accompanying hematological and other consequences (Scylla), or do we provide for adequate tissue levels of vitamin C, which has been thought to carry the risk of oxalosis (Charybdis). Many practitioners are certain that either one outcome (deficiency) or the other (oxalic acid toxicity) is inevitable, and much like Odysseus, no safe course is to be found. The recent accumulating evidence that vitamin C improves the management of anemia in dialysis patients compels us to find a safe passage through this dilemma. The serious vitamin C deficiency seen in many patients may also contribute to poor oral health and chronic fatigue. The evidence for oxalosis from vitamin C supplements stems from hemodialysis as practiced 20 years ago. Investigators using this therapy are not observing systemic oxalosis, and the most current data support the conclusion that vitamin C therapy is safe for dialysis patients. The question will be resolved by controlled trials that address both vitamin C effectiveness and safety.

Antioxidants↗
PubMed1984

Parabolic response of hepatic microsomal hydroxylating system and lipids to graded doses of ascorbic acid in guinea pigs on low and high alpha-tocopherol intake.

The influence of marginal ascorbic acid (AA) deficiency and excessive AA consumption on hepatic microsomal cytochrome P-450, aniline hydroxylase and O-demethylase, serum and liver cholesterol, serum triglycerides and liver alpha-tocopherol was investigated in guinea pigs with low and high vitamin E intake. Male guinea pigs were fed 9 weeks a scorbutogenic diet low in vitamin E (6 mg alpha-tocopherol per kilogram diet), supplemented with four levels of AA: A, deficient, 1 mg AA per animal per day per os; B, control, 500 mg/kg diet; C, control, 5000 mg/kg diet; D, excess, 20,000 mg/kg diet. The response of the microsomal cytochrome P-450 and aniline hydroxylase, serum and liver cholesterol and serum triglycerides to increasing AA doses showed a parabolic pattern. Deficiency (A): high cholesterol in serum and liver, hypertriglyceridemia, low cytochrome P-450 and aniline hydroxylase in liver microsomes; control groups (B and C): decrease of serum and liver cholesterol and serum triglycerides, increase of cytochrome P-450 and aniline hydroxylase; excess (D): return of all parameters to values not significantly different from the AA-deficient group. When guinea pigs were fed the same diets with four levels of AA plus 10 mg alpha-tocopherol acetate per animal orally five times a week, the response of the microsomal hydroxylating system and serum triglycerides to the graded AA doses again proved to be parabolic.

Aniline Hydroxylase↗
PubMed1998

Relationship between glutathione and polyamine metabolism after partial hepatectomy in alcohol-treated rats.

In a liver regeneration inhibiting model after partial hepatectomy in rats, we determined hepatic glutathione concentration and studied its relation with polyamine, an indicator of liver regeneration. Experiment 1: Male ODS rats and Wistar rats as control were maintained with vitamin C-deficient diets for 2 weeks. In the alcohol group, 3 g/kg of ethanol was administered orally 1 hr before partial hepatectomy. Experiment 2: Wistar rats were divided into four groups, according to the presence or absence of alcohol and vitamin E (VE), and a 6-week pair-feeding was done. As for partial hepatectomy, about 70% of the total liver was excised. As a result, in experiment 1, hepatic glutathione levels were significantly decreased by acute alcohol administration in both ODS and Wistar rats, and its level of alcohol administration group of ODS rats was the lowest. Hepatic ornithine decarboxylase activity and putrescine level 4 hr after partial hepatectomy showed almost a similar behavior, being the lowest in the alcohol administration group of ODS rats. In experiment 2, hepatic glutathione level showed no influence by chronic alcohol administration, but was the lowest in the VE-deficient alcohol administration group. Hepatic ODC activity and putrescine level 4 hr after partial hepatectomy showed no influence by chronic alcohol administration, but was the lowest in the VE-deficient alcohol administration group. These results clarified that intrahepatic glutathione levels before partial hepatectomy were decreased in the models in which hepatic ODC activities after surgery were suppressed.

Animals↗
PubMed2006

A combined deficiency of vitamins E and C causes severe central nervous system damage in guinea pigs.

A short period of combined deficiency of vitamins E and C causes profound central nervous system (CNS) dysfunction in guinea pigs. For this report, CNS histopathology was studied to define the nature and extent of injury caused by this double deficiency. Weanling guinea pigs were fed a vitamin E-deficient or -replete diet for 14 d. Then vitamin C was withdrawn from the diet of some guinea pigs. Four diet groups were thus formed: replete, vitamin E deficient, vitamin C deficient, and both vitamin E and C deficient. From 5 to 11 d after institution of the doubly deficient diet, 9 of 12 guinea pigs developed paralysis, and 2 more were found dead. The remaining guinea pig in the doubly deficient group and all animals in the other 3 groups survived without clinical impairment until the experiment was terminated at 13-15 d. Brains and spinal cords were serially sectioned and stained for examination. Only the combined deficiency produced damage in the CNS. The damage consisted mainly of nerve cell death, axonal degeneration, vascular injury, and associated glial cell responses. The spinal cord and the ventral pons in the brainstem were most severely affected, often exhibiting asymmetric cystic lesions. Several features of the lesions suggest that the primary damage was to blood vessels. These results indicate that the paralysis and death caused by combined deficiency of vitamins E and C in guinea pigs is caused by severe damage in the brainstem and spinal cord.

Animals↗
PubMed2003

Plasma vitamin A and C status of in-school adolescents and associated factors in Enugu State, Nigeria.

The study was undertaken to determine the intake of vitamin A and C and plasma concentrations of these vitamins among in-school adolescents. The factors affecting the vitamin status of these adolescents were also determined. Data for this report were obtained from a cross-sectional survey of 600 in-school adolescents in Nsukka local government area (LGA) of Enugu State, Nigeria. Ninety and 45 of the adolescents were randomly selected for determining plasma concentrations of vitamin A and C and intake of these vitamins respectively. Dietary assessment was done using a three-day weighed food intake method. Venous blood samples were collected and used for determining plasma vitamin A using the trifluoroacetic acid (TFA) method, while plasma vitamin C was determined by the thiourea method. Values obtained were matched against standards. The intake of vitamin A by all the adolescents was adequate (126-137% of recommended intake), while the intake of vitamin C was inadequate (51-91% of recommended intake). The mean intake of vitamin C was higher among males (23.7 +/- 0.71-27.3 +/- 8.0) than among females (15.3 +/- 2.8-19.5 +/- 5.1). Despite the adequate intake of vitamin A, 40% of the male and 32% of the female adolescents had low plasma concentrations of the vitamin (< 20 microg/dL). On the other hand, concentrations of plasma vitamin C were low among about 47% of these adolescents. Using multiple regression analysis, the two most important variables influencing vitamin A status were household size (b = -0.629; p < 0.0 1) and nutrition knowledge (b = -1.372; p < 0.01), while for vitamin C status, these were household size (b = -0.110; p = 0.05) and age (b = 0.226; p < 0.05). The daytime students had a significantly (p < 0.05) better vitamin A and C status than the boarders. The prevalence of vitamin A and C deficiencies among the adolescents may be more than estimated due to inadequate intake and/or poor bioavailability. This may pose a serious health risk for adolescents. There is, therefore, a need for adequate nutrition education and awareness about healthy lifestyles among Nigerian adolescents.

Adolescent↗
PubMed1994

Neuromyopathic complications in a patient with anorexia nervosa and vitamin C deficiency.

A 19-year-old female patient with anorexia nervosa developed profound weight loss over 1 year associated with vegetarianism and excessive exercise. There was severe wasting and proximal muscle weakness in the legs and bilateral weakness of eye closure. A purpuric rash developed due to vitamin C deficiency. This case demonstrates a new neurological sign in anorexia nervosa indicating a weakness of the orbicularis oculi muscles as part of a more general myopathy. The myopathic and scorbutic features may have a common pathogenesis.

Adult↗
PubMed2005

Long-term, low-dose, intravenous vitamin C leads to plasma calcium oxalate supersaturation in hemodialysis patients.

BACKGROUND: Ascorbate supplementation for patients on regular dialysis treatment (RDT) is advised to obviate deficiency and improve epoetin response in those with functional iron deficiency. However, clear-cut safety concerns regarding hyperoxalemia are still poorly understood. This study tries to establish safety/efficacy profiles of ascorbate and oxalate during long-term intravenous ascorbate supplementation. METHODS: A prospective study was performed in 30 patients on RDT showing ascorbate deficiency (plasma ascorbate < 2.6 mg/L [<15 micromol/L]): 18 patients were administered intravenous ascorbate during 18 months (250 mg/wk, subsequently increased to 500 mg), and 12 patients were taken as reference untreated cases. Plasma ascorbate and oxalate assays and dialytic balance determinations were performed (ion chromatography and reverse-phase high-performance liquid chromatography, respectively) at baseline, during treatment, and 12 months after withdrawal. RESULTS: Plasma ascorbate levels increased dose dependently with supplementation (1.6 +/- 0.8 mg/L [9.1 +/- 4.6 mumol/L] at baseline, 2.8 +/- 1.8 mg/L [15.9 +/- 10.1 micromol/L]) with 250 mg of ascorbate, and 6.6 +/- 2.8 mg/L [37.5 +/- 16.0 micromol/L] with 500 mg/wk of ascorbate), but only normalized with greater dosages for several months in 94% of patients. Baseline plasma oxalate levels increased from 3.2 +/- 0.8 mg/L (35.8 +/- 8.8 micromol/L) to 3.6 +/- 0.8 mg/L (39.5 +/- 9.1 micromol/L) and 4.5 +/- 0.9 mg/L (50.3 +/- 10.4 micromol/L) with 250 and 500 mg, respectively ( P < 0.001). The calcium oxalate saturation threshold was exceeded by 7 of 18 patients (40%) during 6 months therapy with 500 mg/wk. Ascorbate dialysis removal increased from 37.8 +/- 23.2 mg (215 +/- 132 micromol) to 99.6 +/- 51.7 mg (566 +/- 294 micromol) during supplementation (P < 0.001), with corresponding increases in oxalate removal from 82.5 +/- 33.2 mg (917 +/- 369 micromol) to 111.2 +/- 32.6 mg/L (1,236 +/- 362 micromol; P < 0.01). Withdrawal reverted plasma levels and dialysis removal to initial values. Values for untreated patients did not change during 1 year of follow-up. CONCLUSION: Patients on RDT may resolve ascorbate deficiency with intravenous supplementation of 500 mg/wk, but this implies a significant risk for oxalate supersaturation. Oxalate measurements are strongly recommended during long-term ascorbate therapy.

Adult↗
PubMed2005

Vitamin C deficiency in cancer patients.

PURPOSE: To assess the prevalence of vitamin C deficiency within a group of hospice patients. To assess the relationship between plasma vitamin C, dietary intake and subsequent survival. METHODS: Patients with advanced cancer were recruited from a large hospice. Data were collected on demographic details, physical functioning and smoking history. An estimate was obtained of the number of weekly dietary portions consumed equivalent to 40 mg of vitamin C, the recommended daily intake. Plasma vitamin C was measured by a single blood sample. The study had local ethical approval. RESULTS: Fifty patients were recruited (mean age 65.2 years, 28 female). Plasma vitamin C deficiency was found in 15 (30%). Dietary intake of vitamin C was correlated to plasma vitamin C (r=0.518, P<0.0001). Low dietary intake, low albumin, high platelet count, high CRP level and shorter survival were all significantly associated with low plasma vitamin C concentrations (<11 micromol/L). There was no correlation between plasma vitamin C, smoking history or physical functioning. CONCLUSION: Vitamin C deficiency is common in patients with advanced cancer and the most important factors determining plasma levels are dietary intake and markers of the inflammatory response. Patients with low plasma concentrations of vitamin C have a shorter survival.

Acute Disease↗