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Results for “ASCORBIC ACID DEFICIENCY”
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Zinc and vitamin C in the aetiology of pressure sores.
A review of studies which have considered the role of two important nutrients in the development of pressure sores.
Iron absorption and therapy after gastric bypass.
BACKGROUND: Iron deficiency anemia is a common complication of gastric bypass. The authors assessed the value of taking vitamin C with oral iron in correcting deficiencies in iron stores and anemia postoperatively. MATERIALS AND METHODS: Iron absorption tests were performed on 55 patients 3.2+/-2.0 years after isolated gastric bypass to identify those at higher risk for the late development of anemia. Twenty-nine of this group agreed to a therapeutic trial of iron alone or with vitamin C over a 2-month period. All 55 patients were followed up for 27.1+/-1.0 months following the study. RESULTS: The iron absorption test identified patients with low iron stores, as indicated by low serum ferritin, and those with sufficient absorption surface to benefit from oral iron. The addition of vitamin C appears to enhance the therapeutic effect of iron by correcting ferritin deficits (P < 0.01) and anemia (P < 0.05). Differences in intestine length bypassed by the operation (10 vs. 100 cm) did not affect late ferritin and hemoglobin values. CONCLUSION: This study suggests but does not prove that the addition of vitamin C to iron therapy after gastric bypass is more effective in restoring ferritin and hemoglobin than iron alone. These results are in contrast with the outcome 22.8 months later, when approximately 50% of study patients were again anemic. Closer follow-up of patients is urgently needed.
Influence of L-ascorbate on the concentrations of microsomal cytochrome P-450 and cytochrome b5 in adrenals, kidneys and spleen of guinea pigs.
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Inadequate levels of essential nutrients in developed nations as a risk factor for disease: a review.
Inadequate levels of essential nutrients is a most important factor in environmental health, leading to an almost monotonic increase in the incidence, morbidity, mortality, and associated costs of 'diseases of affluence' that has persisted for circa a century. Such an unprecedented human tragedy can be explained by the (1) flawed belief that essential nutrients can be replaced by xenobiotic molecules--a fundamental error, (2) failure to recognize that the levels of certain essential nutrients in diets available in the environment are not adequate to produce optimum health, longevity or resistance, and (3) failure to recognize that the refined diet has a lower essential nutrient content. Such beliefs contribute to early death in affluent nations.
The serumtyrosine level as an index of thyroid function.
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The effect of controlled ascorbic acid depletion and supplementation on periodontal health.
To determine if systemic levels of vitamin C influence periodontal health, changes in plaque accumulation, gingival health and periodontal probing depth were measured in healthy subjects housed for 3 months in a nutrition suite that provided controlled periods of ascorbic acid depletion and supplementation. Eleven healthy, nonsmoking men, aged 19 to 28 years, ate a rotating 7-day diet adequate in all nutrients except ascorbic acid. This basal diet, which contained less than 5 mg/day ascorbic acid, was supplemented with 60 mg/day ascorbic acid for 2 weeks, 0 mg/day ascorbic acid for 4 weeks, 600 mg/day ascorbic acid for 3 weeks and 0 mg/day ascorbic acid for 4 weeks. Plasma, urine and leukocyte ascorbate levels, Plaque Index, Gingival Index, Bleeding Index and probing depths were monitored throughout the study. A uniform oral hygiene program was maintained in which oral hygiene instructions were reinforced bi-weekly. Ascorbate concentrations in body fluids and leukocytes responded rapidly to changes in ascorbic acid intake. No mucosal pathoses or changes in plaque accumulation or probing depths were noted during any of the periods of depletion or supplementation. However, measures of gingival inflammation were directly related to the ascorbic acid status. The results suggest that ascorbic acid may influence early stages of gingivitis, particularly crevicular bleeding.
Dietary vitamin C and the risk for periodontal disease.
BACKGROUND: Vitamin C has long been a candidate for modulating periodontal disease. Studies of scorbutic gingivitis and the effects of vitamin C on extracellular matrix and immunologic and inflammatory responses provide a rationale for hypothesizing that vitamin C is a risk factor for periodontal disease. METHODS: We evaluated the role of dietary vitamin C as a contributing risk factor for periodontal disease utilizing the Third National Health and Nutrition Examination Survey (NHANES III) which is representative of the U.S. civilian, non-institutionalized population. RESULTS: A sample of 12,419 adults (20 to 90+ years of age), with dental measurements and assessment of dietary information as well as demographic and medical histories were included in the studies. Dietary vitamin C was estimated by a 24-hour dietary record. Individuals with periodontal disease were arbitrarily defined as those who had mean clinical attachment levels of > or =1.5 mm. Using multiple logistic regression analysis, we found a relationship between reduced dietary vitamin C and increased risk for periodontal disease for the overall population (odds ratio [OR] = 1.19; 95% CI: 1.05 to 1.33). Current and former tobacco users who were taking less dietary vitamin C showed an increased risk of periodontal disease with OR of 1.28, 95% CI: 1.04 to 1.59 for former smokers, and an OR of 1.21, 95% CI: 1.02 to 1.43 for current tobacco users. There was a dose-response relationship between the levels of dietary vitamin C and periodontal disease with an OR of 1.30 for those taking 0 to 29 mg of vitamin C per day, to 1.16 for those taking 100 to 179 mg of vitamin C per day as compared to those taking 180 mg or more of vitamin C per day. CONCLUSION: Dietary intake of vitamin C showed a weak, but statistically significant, relationship to periodontal disease in current and former smokers as measured by clinical attachment. Those taking the lowest levels of vitamin C, and who also smoke, are likely to show the greatest clinical effect on the periodontal tissues.
The influence of smoking on vitamin C status in adults.
To further define the relation between smoking and vitamin C status, the dietary and serum vitamin C levels of 11,592 respondents in the second National Health and Nutrition Examination Survey (NHANES II) were analyzed. Smokers of 20 cigarettes daily had the lowest vitamin C dietary intake (79 mg, 95% CI:73, 84) and serum levels (0.82 mg/dl, 95% CI: 0.77, 0.86; 46.6 mumol/L, 95% CI: 43.7, 48.8), while smokers of 1-19 cigarettes daily had decreased vitamin C intake (97 mg; 95% CI: 90, 104 mg) and serum levels (0.97 mg/dl, 95% CI: 0.92, 1.03; 55.1 mumol/L, 95% CI: 52.2, 58.5) compared to respondents who had never smoked (109 mg, 95% CI: 105, 113 and 1.15 mg/dl, 95% CI: 1.11, 1.18; 65.3 mumol/L, 95% CI: 63.0, 67.0, respectively). This inverse association between both intake and serum levels of vitamin C and smoking was independent of age, sex, body weight, race, and alcoholic beverage consumption. Following further adjustment for dietary vitamin C intake, the negative correlation between cigarette smoking and serum vitamin C levels persisted. The risk of severe hypovitaminosis C (serum levels less than or equal to 0.2 mg/dl; 11.4 mumol/L) was increased in smokers, particularly when not accompanied by vitamin supplementation (odds ratio 3.0, 95% CI: 2.5, 3.6). These data suggest that even though smoking adversely affects preferences for vitamin C rich foods, the inverse association between smoking and serum vitamin C levels occurs independently of dietary intake.
Stress and nutrition in relation to excess development of chronic disease in Puerto Rican adults living in the Northeastern USA.
Although health disparities are well documented among minority populations, they have not been fully explained by socio-economic status. We have demonstrated that Puerto Rican elders in Massachusetts are significantly more likely to have physical disability, depression, cognitive impairment, diabetes and other chronic health conditions than do non-Hispanic white elders living in the same neighborhoods. This suggests that the disparity is not due only to physical or neighborhood location, and that other factors must be influencing these differences. In that study, we also showed that the Puerto Rican elders had diets that were limited in diversity and were relatively low in micronutrient content. In our ongoing cohort study within our Boston Puerto Rican Center for Population Health and Health Disparities, we are investigating the relationships between psychosocial stress, its effect on physiologic burden or "allostatic load" and, in turn, how this is associated with the functional outcomes previously identified as areas of health disparity: depression, cognitive impairment and functional limitation. We further propose that the association between life stress, physiologic response and chronic conditions is modified by nutritional status, with a focus on B vitamins and antioxidant vitamins.
Vitamin C: basic metabolism and its function as an index of oxidative stress.
Vitamin C (ASC) is well known as an outstanding antioxidant in animal tissues. This concept is reviewed from a chemical standpoint, starting from a chemical view of radical reactions in the cell. ASC, vitamin E, and lipid hydroperoxide were selected as key molecules involved in radical reactions in the cell, and their efficiencies as an index of oxidative stress were evaluated. At first, methods for specific and sensitive determination of ASC and lipid hydroperoxide were developed. Based on comparisons of these indices during oxidative stress in typical pathological conditions, such as diabetes and liver damage by toxicants, ASC concentration was found to be the most sensitive index in animal tissues. Antioxidative effect of food factors in vivo can be evaluated on the basis of these indices. Analysis of oxidation of low-density lipoprotein (LDL) revealed that degradation and cross-link of apolipoprotein B-100 (apoB) are extremely facile processes. Fragmented and conjugated apoB proteins are present in normal human serum, and tend to increase with age based on immunoblot analysis. Estimation of these products allows us a mechanism-based diagnosis of atherosclerosis. A significant relationship between plasma ASC level and the sum of these apoB products was found. In conclusion, specifically determined ASC concentration sensitively reflects oxidative stress in tissues.
Iron supplementation in pregnancy: is less enough? A randomized, placebo controlled trial of low dose iron supplementation with and without heme iron.
BACKGROUND: The purpose of the present study was to evaluate the efficacy of low dose iron supplementation with and without a heme component, prescribed for women in the second half of pregnancy. METHOD: A randomized, double-blind, placebo controlled trial. Thirty-one women received a daily dose of 27 mg elemental iron in a product containing both heme iron and non-heme iron (Hemofer), 30 women received the same dose as pure non-heme iron with vitamin C (Collets jern med vitamin C), and 29 women received placebo. A double dummy technique was used to mask tablets. The women were tested for red cell indices and iron status markers (s-ferritin, s-iron, Total Iron Binding Capacity and erythrocyte protoporphyrin) throughout pregnancy and 8 and 24 weeks postpartum. The results were analyzed according to the 'intention to treat' principle. RESULTS: The hematological effects were equal in the two treatment groups. 25% of the supplemented women fell below 110 g/l in Hb vs 52% in the placebo group (p < 0.05); none fell below 100 g/l in the supplemented groups, 14% in the placebo group. Iron status was significantly better for all measured parameters in the heme iron group compared to placebo at the end of pregnancy. Differences between the other groups were only shown for some parameters, probably due to the small sample size. In the heme iron group there were fewer women with empty iron stores postpartum than at the start of pregnancy (from 14% to 8%), in the non-heme iron group there was a significant increase (from 3% to 27%), and in the placebo group the percentage of women with empty iron stores was more than doubled (from 21% to 52%). CONCLUSIONS: A daily dose of 27 mg elemental iron, containing a heme component, given in the second half of pregnancy, prevents depletion of iron stores after birth in most women. An equivalent dose of pure inorganic iron seems less effective, but the sample size in this study was too small to demonstrate significant differences between the two treatment groups.
The role of ascorbic acid in drug metabolism.
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Vitamin C and cholesterol metabolism.
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Osteogenesis after bone and bone marrow transplantation. Studies of cellular behaviour using combined myelo-osseous grafts in the subscorbutic guinea pig.
In order to study factors influencing osteogenesis after bone and bone marrow transplantation, we have caused guinea pigs to become scorbutic, and looked at the cell morphology at sites of bone formation. We had previously studied normal guinea pigs and found that autologous marrow in intermuscular implants was associated with bone production by the ninth day, regardless of the type of stored allogeneic bone transplanted with it. In subscorbutic guinea pigs, using identical implants, bone did not appear within the first 13 days, and the cell population around the implants was different. These experiments support the dominant role of bone marrow cells in osteogenesis and cast further doubt on the primary role of devitalised bone as an inducer of bone formation. Interference with cell function by deprivation of a single essential molecule, Vitamin C, produces great change in the ability of cells to synthesise bone, or pre-osseous matrix.
The biosynthesis of collagen.
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[The relationship between illness in the aged and in inherently scorbutic rats (ODS rats)].
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