Plasma Levels Of Antioxidant Vitamins Research Articles

Lower Plasma Levels of Antioxidant Vitamins in Patients with Metabolic Syndrome: A Case Control Study.

Metabolic syndrome (MS) is a coexistence of metabolic risk factors affecting the development of cardiovascular diseases. Reactive oxygen species, which are excessively produced in MS, participate in its pathogenesis. Vitamins A, C and E are an important part of the non-enzymatic antioxidative barrier in humans. The aim of the study was to estimate plasma vitamin A, C and E levels and the intake of these vitamins from the diet in patients with MS. The study included 182 patients with MS, 94 men and 88 women, aged 30-65 years (mean 57.31 ± 8.28 years). The control group was comprised of 91 subjects, 56 men and 35 women, aged 41-65 years (mean 57.75 ± 5.84 years). The MS diagnosis was based on IDF criteria. The determination of the serum level of vitamin A, C and E was performed using the spectrophotometric method. The food intake was assessed by 24-h dietary recall. The mean plasma vitamin A, C and E levels were significantly lower in MS patients than in the controls (p = 0.05). No correlation was found between vitamin A, C and E intake from the diet and their plasma concentrations in MS patients. Plasma vitamin A, C and E deficiency was observed significantly more often in MS patients than in the control group (15.38% vs. 2.19%, 79.12% vs. 8.79% and 60.45% vs. 5.49%, p < 0.0001, respectively). BMI was the one factor significantly affecting the mean value of vitamin A, C and E levels in MS patients. MS patients demonstrated significantly lower plasma levels of vitamin A, C and E compared to the healthy subjects. Lower plasma levels of antioxidant vitamins with their high intake from the diet indicate antioxidant barrier impairment in MS patients.

Antioxidant vitamins and lipid peroxidation status in noncyclic versus cyclic ewes subjected to ram effect, before mating

This study assessed the levels of plasma vitamins A, E, and C and the lipid peroxidation status of cyclic and noncyclic ewes during pre-breeding week after a period of poor nutrition. The study was conducted on 100 crossbred fat-tailed adult ewes with body condition scores of 2.5 to 3.5, grazing on medium-to-low quality forages during summer. During 3 weeks of flushing, the ewes were fed alfalfa hay (40 %) and wheat straw (60 %) ad libitum plus 300 g of barley grain/head/day in addition to the available pasture. The ewes had been isolated for 2 months during summer and, thereafter, were kept in close proximity of the rams for 1 week before ram release. Whole blood samples were collected 7 days (day −7) and a few hours before ram release (day 1). Plasma progesterone (P4, marker of ovulation) and antioxidant vitamins and hemolysate malondialdehyde (MDA, marker of lipid peroxidation) were measured. Plasma P4 was also measured in an additional sample taken 14 days after ram release. Twenty-eight percent of ewes were noncyclic in both pre-breeding samplings (P4 ≤ 1 ng/mL). On day −7, the noncyclic ewes had higher levels of MDA (P = 0.027), but the antioxidant vitamins were not different between cyclic and noncyclic ewes (P > 0.05). On day 1, all antioxidant vitamins declined significantly in cyclic ewes, whereas they remained almost constant (P > 0.05) in noncyclic animals. At this time, MDA concentration increased in the cyclic ewes (P = 0.014). At day 14, after ram introduction, the proportion of noncyclic ewes reduced to 13 %. Oxidative stress may postpone the ewe’s cyclicity at the beginning of the breeding period but may be alleviated after a while. This may cause delayed conception and extended lambing periods. Ovarian cyclicity is capable of reducing the plasma levels of antioxidant vitamins and increases the level of lipid peroxidation.

Plasma zinc antioxidant vitamins, glutathione levels and total antioxidant activity in oral leukoplakia

Leukoplakia is a common, potentially premalignant lesion with malignant transformation rate from 1 to 17% with highest transformation rate for the lesions on the floor of the mouth, soft palate and tongue. One of the main etiological factors is consuming areca nut and its commercial preparations which generate high levels of reactive oxygen species during their metabolism. So the aim of this present study is to evaluate the plasma levels of antioxidant vitamins, antioxidant mineral zinc, glutathione and total antioxidant status (TAS) in leukoplakia patients. For this cross-sectional study, we selected 23 newly diagnosed oral leukoplakia patients of both sexes within the age group 28-40 years and the same number of age and sex matched healthy individuals without having history of any systemic illness were selected as control group. In both the groups, we measured plasma antioxidant vitamins A, C, E, antioxidant mineral zinc, GSH and TAS. Student's t test was applied and the P value <0.001 was considered as statistically significant. We observed very low levels of antioxidant vitamins A, C, E, antioxidant mineral zinc and antioxidant metabolite GSH (P<0.001) and at the same time we also observed very poor (TAS) (P<0.001) in leukoplakia patients when compared to patients in control group. The consumption of tobacco or areca quid which contains high copper levels creates an oxidative stress like environment during their metabolism, might play a major role in causation and propagation of oral leukoplakia.

Blood cells as functional markers of antioxidant vitamin status

Antioxidants have shown beneficial effects in several biological systems, in which they were able to prevent oxidative stress-associated damage. Vitamins C and E are key antioxidants in man. Dietary intake cannot accurately reflect plasma vitamin levels. However, the plasma levels of antioxidant vitamins could also reflect the acute assimilation of these vitamins. It has been pointed out that antioxidant vitamin blood contents reach a saturation level by intake of dietary supplements. Antioxidant vitamin plasma levels are the parameter most used to determine antioxidant status. However, the vitamin plasma levels may not reflect the nutritional status of vitamins. It has been pointed out that the vitamin E in adipose tissue can be used as a measure of vitamin E status. To determinate antioxidant vitamin contents in lymphocytes and neutrophils after exercise is a useful tool to assess the functional status of antioxidant vitamins.

Total antioxidant capacity of the diet is inversely and independently related to plasma concentration of high-sensitivity C-reactive protein in adult Italian subjects

Inflammation, a risk factor for cardiovascular disease, is associated with low plasma levels of antioxidant vitamins. In addition to vitamins, other antioxidants modulate the synthesis of inflammatory markers in vitro and contribute to the total antioxidant capacity (TAC) of a diet. However, the relationship between dietary TAC and markers of inflammation has never been evaluated in vivo. We investigated the relationship between dietary TAC and markers of systemic (high-sensitivity C-reactive protein (hs-CRP), leucocytes) and vascular (soluble intercellular cell adhesion molecule-1) inflammation in 243 non-diabetic subjects. General Linear Model (GLM) analysis showed a significant (P=0.005) inverse relationship between hs-CRP and quartiles of energy-adjusted dietary TAC, even when recognized modulating factors of inflammation, namely alcohol, fibre, vitamin C, alpha-tocopherol, beta-carotene, BMI, waist circumference, HDL-cholesterol, hypertension, insulin sensitivity and plasma beta-carotene, were included in the model as covariates (P=0.004). The relationship was stronger for subjects with hypertension (P=0.013 v. P=0.109 for normotensive individuals). Among dietary factors, TAC was significantly higher (5.3 (sd 3.0) v. 4.9 (sd 2.7) mmol Trolox/d; P=0.026) in subjects with low plasma hs-CRP (range: 0.0-4.1 mg/l) than in subjects with high plasma hs-CRP (range: 4.2-27.8 mg/l). We conclude that dietary TAC is inversely and independently correlated with plasma concentrations of hs-CRP and this could be one of the mechanisms explaining the protective effects against CVD of antioxidant-rich foods such as fruits, whole cereals and red wine. This could be of particular significance for subjects with high blood pressure.

Ascorbic Acid and Alpha Tocopherol Antioxidant Status of Type 2 Diabetes Mellitus Patients seen in Lagos

This study was carried out with the aim of assessing the plasma status of ascorbic acid and alpha-tocopherol in Nigerian type 2 diabetes mellitus patients It was a cross sectional study, made up of 70 type 2 diabetes mellitus patients and 40 healthy controls. The plasma levels of vitamins C and E were measured, so also were the fasting plasma glucose (FPG) and glycosylated haemoglobin (HbA1C). Results showed significantly lower plasma levels of vitamin C and vitamin E in the patients, compared with the controls. The correlation studies between vitamins C and E on the one hand, versus (FPG) and HbA1c on the other hand were not contributory.The conclusion from this study, is that, there is a reduction in plasma levels of anti-oxidant vitamins C and E in type 2 DM but this does not have any particular relationship with the levels of FPG or HbA1C. type 2 Dm, ascorbic Acid, alpha tocopherol antioxidant status.

Antioxidant response to oxidative stress induced by exhaustive exercise

The aim of this work was to demonstrate the occurrence of oxidative stress during exhaustive exercise and to determine the antioxidant response. Eight voluntary male subjects participated in this study. The exercise was a cycling mountain stage (171 km) and the cyclists took a mean±S.E.M. time of 270±12 min to complete it. Blood samples were taken before the cycling stage, immediately after the stage, 3 h after finishing the stage and on the morning of the following day. We determined the activities of erythrocyte antioxidant enzymes, blood levels of oxidised glutathione, plasma levels of antioxidant vitamins and carotenoids, and the serum lipid and cholesterol profile. The mountain cycling stage induced significant increases in catalase and glutathione reductase activities. Significant decreases in glutathione peroxidase activity, both determined with hydrogen peroxide and with cumene hydroperoxide as substrates, were observed. Blood oxidised glutathione and serum uric acid rose after the stage. Plasma vitamin E increased after the stage but dropped to below basal values after 3 h of recovery. Triglycerides and VLDL-cholesterol increased significantly after the stage and remained high 3 h after the cycling stage. The mountain cycling stage induced oxidative stress, as was evidenced by the increases in blood GSSG and in serum urate concentrations and by the pattern of change of erythrocyte antioxidant enzyme activities. A specific utilisation of α-tocopherol against oxidative stress during recovery was evidenced.

Relation between deranged antioxidant system and cervical neoplasia

The purpose of this study was to compare the plasma levels of the anti-oxidant system and oxidative stress between a cervical neoplasia group and a normal control group and to investigate the relationship between the levels of micronutrients of antioxidant system and various clinicopathological parameters of cervical carcinoma. A cross-sectional sample of 180 women, including 90 normal controls, was recruited from November 2000 to January 2001. Plasma concentration of malondialdehyde (MDA) was spectrophotometrically measured as the parameter of lipid peroxidation. Plasma levels of antioxidant vitamins were analyzed with the help of reverse-phase, high-pressure liquid chromatography, whereas glutathione peroxidase activity was evaluated by using coupled enzyme procedure. While the activity of glutathione peroxidase and the plasma levels of antioxidant vitamins, such as lutein, β-carotene, lycopene, and zeaxanthin, were all significantly lower, the concentration of MDA was significantly higher in women with cervical intraepithelial neoplasia (CIN) or invasive cervical cancer, compared to those of the normal control group. The status of the plasma antioxidant system showed no significant correlation with the prognostic factors of cervical cancer. These findings suggest a potential role of oxidative stress-induced lipid peroxidation and the impairment of the anti-oxidant system in the pathogenesis of CIN and carcinoma of the uterine cervix.

Relation between deranged antioxidant system and cervical neoplasia

The purpose of this study was to compare the plasma levels of the anti-oxidant system and oxidative stress between a cervical neoplasia group and a normal control group and to investigate the relationship between the levels of micronutrients of antioxidant system and various clinicopathological parameters of cervical carcinoma. A cross-sectional sample of 180 women, including 90 normal controls, was recruited from November 2000 to January 2001. Plasma concentration of malondialdehyde (MDA) was spectrophotometrically measured as the parameter of lipid peroxidation. Plasma levels of antioxidant vitamins were analyzed with the help of reverse-phase, high-pressure liquid chromatography, whereas glutathione peroxidase activity was evaluated by using coupled enzyme procedure. While the activity of glutathione peroxidase and the plasma levels of antioxidant vitamins, such as lutein, beta-carotene, lycopene, and zeaxanthin, were all significantly lower, the concentration of MDA was significantly higher in women with cervical intraepithelial neoplasia (CIN) or invasive cervical cancer, compared to those of the normal control group. The status of the plasma antioxidant system showed no significant correlation with the prognostic factors of cervical cancer. These findings suggest a potential role of oxidative stress-induced lipid peroxidation and the impairment of the anti-oxidant system in the pathogenesis of CIN and carcinoma of the uterine cervix.

Plasma levels of antioxidant vitamins C and E are decreased in vascular parkinsonism

Oxidative stress is an important mechanism of cell death in Parkinson's disease (PD) and brain ischemia. Vitamins C, E and A are important antioxidants and deficiency of these agents has been implicated in the mechanisms of atherosclerosis. We measured the levels of the above antioxidant vitamins in 44 patients with PD, 12 patients with vascular parkinsonism (VP), 11 patients with other parkinsonism syndromes of various causes and 39 controls. Vitamin A levels did not differ between groups. Vitamins C and E were found decreased in VP, while they were normal in PD indicating low levels of antioxidant vitamins in VP and stressing the necessity of maintaining sufficient dietary intake of these agents in the elderly.

Effect of exercise intensity and training on antioxidants and cholesterol profile in cyclists

The aim of this work was to evaluate the effect of different intensity of exercise and different training status on antioxidants and cholesterol profile in cyclists. 33 male cyclists (17 amateur and 16 professional cyclists) participated in this study. The amateurs all trained 14 ± 1 h each week, and their VO 2 max was 62.5 ± 1.8 ml/Kg.min; the professionals all trained 24 ± 1 h each week, and their VO 2 max was 80.2 ± 1.6 ml/Kg.min. Amateurs were submitted to the maximal and submaximal prolonged exercise tests. Professionals were submitted to a mountain stage (170 km) of cycling competition. Serum lipid and cholesterol profile (triglycerides, total cholesterol, HDL-cholesterol, LDL-cholesterol and VLDL-cholesterol) and plasma antioxidant capacity (ascorbic acid, α-tocopherol, retinol, β-carotene and others) were measured before and after exercise tests. Hematological determinations (number of erythrocytes, hematocrit and hemoglobin concentration) and dietary intake were also measured. No significant differences were observed in basal values (before exercise tests) of amateur and professional cyclists. Negligible differences were found between dietary intake of amateur and professional cyclists, and also the results of hematological values showed there was no effect of degree of hydration or dietary intake on blood levels of studied antioxidant and lipid parameters. An increase in plasma levels of vitamin C, vitamin E, triglycerides and VLDL-cholesterol levels, and also a decrease of β-carotene and LDL-cholesterol. were observed in well-trained professional cyclists after the cycling stage - an endurance exercise - but not in amateur cyclists. Amateur cyclists showed only mild increases in total cholesterol after maximal and submaximal exercise, while a rise in HDL-cholesterol was only observed after maximal exercise; none of these changes were observed in professional cyclists. Plasma levels of antioxidant vitamins and carotenes, and also serum lipids, total cholesterol and lipoprotein-cholesterol showed an overall response to exercise, and their increase and/or decrease must be explained as a consequence of the different training status of sportsmen and intensity and duration of exercise tests.

Antioxidant vitamins and the risk of carotid atherosclerosis: The perth carotid ultrasound disease assessment study (CUDAS)

OBJECTIVESThis study examined whether dietary intake or plasma levels of antioxidant vitamins were independently associated with common carotid artery intima-media (wall) thickness (IMT) or focal plaque, or both, in a large, randomly selected community population.BACKGROUNDOxidation of low-density lipoprotein (LDL) cholesterol is thought to be important in early atherogenesis. Antioxidant micronutrients may therefore protect against lipid peroxidation and atherosclerotic vascular disease.METHODSWe studied 1,111 subjects (558 men and 553 women; age 52 ± 13 years [mean ± SD], range 27 to 77). We measured dietary vitamin intake and fasting plasma levels of vitamins A, C and E, lycopene and alpha- and beta-carotene and performed bilateral carotid artery B-mode ultrasound imaging.RESULTSAfter adjustment for age and conventional risk factors, there was a progressive decrease in mean IMT, with increasing quartiles of dietary vitamin E intake in men (p = 0.02) and a nonsignificant trend in women (p = 0.10). Dietary vitamin E levels accounted for 1% of the variance in measured IMT in men. For plasma antioxidant vitamins, there was an inverse association between carotid artery mean IMT and plasma lycopene in women (p = 0.047), but not in men. None of the other dietary or plasma antioxidant vitamins, nor antioxidant vitamin supplements, were associated with carotid artery IMT or focal carotid artery plaque.CONCLUSIONSThis study provides limited support for the hypothesis that increased dietary intake of vitamin E and increased plasma lycopene may decrease the risk of atherosclerosis. No benefit was demonstrated for supplemental antioxidant vitamin use.

Randomized, Double-blind Placebo-controlled Trial of Coenzyme Q10 in Chronic Renal Failure: Discovery of a New Role

Purpose: Antioxidant vitamin and coenzyme Q10 deficiency as well as oxidative damage have been observed in patients with chronic renal failure. In this study, we examine whether treatment with coenzyme Q10 can improve renal function in chronic renal failure. Design: Randomized, double-blind, placebo-controlled trial. Materials and Methods: Subjects ( n = 21) with available records of chronic renal failure on dialysis or not on dialysis (serum creatinine 5 mg dl -1 or above) were randomly divided into intervention ( n = 11) and control ( n = 10) groups by blindly selecting a card. The intervention group was administered coenzyme Q10 (60 mg thrice daily) and the placebo group inert fibre (cellulose, 1 g thrice daily) for a period of 4 weeks. Results: The coenzyme Q10 group showed a significant reduction in serum creatinine, blood urea and a significant increase in creatinine clearance and urine output compared to the placebo group after the 4-week trial period, while the baseline values of these parameters were comparable between the two groups. The frequency of dialysis and the proportion of subjects on dialysis were comparable at baseline. However, after 4 weeks, the subjects on dialysis were significantly fewer in the coenzyme Q10 group than the placebo group (36.2% vs. 90.0% , p < 0.02). Plasma levels of antioxidant vitamins A, E and C and beta-carotene showed a significant increase whereas thiobarbituric acid reactive substances, diene conjugates and malondialdehyde showed a significant reduction in the coenzyme Q10 group compared to the control group. Conclusions: Treatment with coenzyme Q10 improves renal function in patients with chronic renal failure and decreases the need for dialysis in patients on chronic dialysis. Long-term follow-up in a large number of patients would be necessary to confirm these results.

Plasma levels of antioxidant vitamins and cholesterol in a large population sample in central-northern Italy.

In a population-based multicenter case-control study of diet, life-style, and gastric cancer a large series of adults, aged 30-75 years (mean 58.9 years), were randomly sampled from the general population in 3 areas of Central-Northern Italy. To evaluate the relationship between plasma levels of antioxidant vitamins and cholesterol, and sociodemographic characteristics, life-style factors, and dietary intake of selected nutrients in a sample of the Italian population. A fasting blood sample was available for 945 subjects (553 men, 392 women). The plasma concentrations of ascorbic acid, carotene, retinol, alpha-tocopherol, and cholesterol were determined by a centralized laboratory. All participants answered to a detailed questionnaire collecting information on sociodemographic and anthropometric characteristics, smoking, alcohol drinking, and dietary habits. Covariance analysis models, with post hoc Dunnett tests, including terms for age, sex, study center, and period of blood drawing, were used for selected multiple-way comparisons of mean values of plasma nutrients. Mean plasma values of retinol were higher among men while women had higher levels of plasma carotene, ascorbic acid, alpha-tocopherol, and cholesterol. Plasma carotene levels showed an inverse association with body mass index, alcohol consumption, and smoking and a positive association with social class. Carotene concentrations were higher in plasma samples obtained in spring/summer, while ascorbic acid levels were higher in autumn/winter. Partial correlation co-efficients between plasma vitamin levels showed a strong correlation between carotene and ascorbic acid (0.69 in men; 0.74 in women), between carotene and alpha-tocopherol (0.44; 0.37), and between alpha-tocopherol and ascorbic acid (0.45; 0.41). Plasma alpha-tocopherol and retinol correlated with plasma cholesterol. On the other hand, plasma carotene and ascorbic acid were correlated with their estimated dietary intakes, while the intakes of other nutrients, as expected, correlated rather poorly with the respective plasma concentrations. Socio-economic factors, life-style, and specific nutrient intake, in addition to gender, are related to nutrient plasma levels in Italian adults and may provide specific suggestions for the prevention of chronic diseases.

Could antioxidants play a role in high rates of coronary heart disease in the Czech Republic?

To compare plasma levels of antioxidant vitamins in the Czech population with those in a western European population, and to investigate whether plasma levels of antioxidant vitamins in Czech population are related to risk of MI. The study has two parts: a cross-sectional survey and a population based case-control study. Adult population in two districts of the Czech Republic, and London based civil servants group as the comparison. A random sample of men and women aged 25-64y resident in two districts were selected for the cross- sectional survey. Subjects in the age group 40-49 y were compared to a sample of British civil servants of the same age enrolled in the Whitehall II Study. Men in the Czech sample served as controls to 52 male cases of first non-fatal myocardial infarction (MI) which occurred in the same population. Plasma samples were obtained from venepuncture during an interview in hospital in the population sample and immediately after hospitalization in the MI cases. Plasma levels of beta-carotene and alpha-tocopherol, and the event of MI. Identical protocol and one laboratory was used for all analyses. The mean plasma levels of beta-carotene and alpha-tocopherol in healthy Czech men and women were substantially lower than in a subsample of British civil servants examined in the same laboratory. Smoking was strongly related to beta-carotene in both populations but differences between Czechs and Brits were present in both smokers and non-smokers. In the case-control study among Czech men, low levels of the vitamins were strongly related to an increases risk of MI. Age-adjusted odds ratios for concentrations below the median were 3.33 (95% confidence interval 1.43-8.33) for beta-carotene and 1.89 (0.94-3.45) for alpha-tocopherol; further adjustment for a range of variables reduced these estimates only slightly. Plasma concentrations of antioxidants in the Czech population appeared to be very low, and men with low levels of these substances are at increased risk of MI. This indicates that sub-optimal intake of antioxidants or related dietary factors may have played a role in the high rates of coronary heart disease in this population.

Plasma Levels of Antioxidant Vitamins, Selenium, Total Sulfhydryl Groups and Oxidative Products in Ischemic-Stroke Patients as Compared to Matched Controls in Taiwan

The possible involvement of oxidative damage and antioxidant protection has been suggested in the patho-genesis of stroke which is the second-leading cause of death in Taiwan. In this study we investigated the relationship between ischemic stroke and plasma status of antioxidants and oxidative products. Plasma levels of vitamin A, α -tocopherol, carotenoids, selenium (Se), total SH groups (T-SH), thiobarbituric acid-reactive substances (TBARS) and protein carbonyl, a marker of protein damage, were determined in ischemic-stroke patients (n = 36, blood sampled within 24 hrs after the clinical event) in comparison with 21 matched controls. The cholesterol-adjusted carotenoids and vitamin E were significantly lower (P < 0.05) in the plasma of ischemic-stroke patients than those of the controls. TBARS were higher (P < 0.05) in the patients than in the controls but Se, T-SH and protein carbonyls were not significantly different between the two groups. Sepration of the patients into small-artery ischemic stroke (SAIS, n = 17) and large-artery ischemic stroke (LAIS, n = 19) groups revealed that both carotenoids/ cholesterol and vitamin E/cholesterol ratios were significantly lower in both LAIS and SAIS groups than the controls (n = 21) whle vitamin A/cholesterol was not different among the three groups. TBARS were only significantly higher in the LAIS group. The results demonstrated that, within 24 hrs after the clinical event, the acute-ischemic stroke patients had lowered levels of cholesterol-adjusted carotenoids and α-tocopherol but elevated levels of TBARS in the plasma as compared to the matched controls. It remains to be resolved as to whether enhanced lipid peroxidation is a cause or a result of lowered antioxidants in ischemic stroke.

Epidemiologic study of trace elements and magnesium on risk of coronary artery disease in rural and urban Indian populations.

To determine the association of trace elements and magnesium with risk of coronary artery disease (CAD) in rural and urban populations of India.Cross-sectional surveys on the randomly selected municipal streets in Moradabad city and one village in Moradabad tahsil in North India.There were 162 rural (86 men and 96 women) and 152 urban (80 men and 72 women) subjects between 26 to 65 years of age. Evaluations were obtained by physician- and dietitian-administered, validated questionnaires, physical examination, electrocardiogram and blood examination.The prevalence of CAD and coronary risk factors was 2.5 times higher in the urban population compared to rural subjects (8.6 vs. 3.0%). In rural subjects, dietary intakes and plasma levels of vitamins and minerals were comparable with those of urban subjects except for higher dietary intake of magnesium in rural subjects and higher plasma vitamin A level in urban subjects. In both rural and urban subjects, low serum zinc (80 +/− 82 vs. 110 +/− 11.0 micrograms/dl, p < 0.05) and magnesium levels (1.60 +/− 0.36 vs. 1.71 +/− 0.41 mEQ/L, p < 0.05) and lower zinc/copper ratio (0.58 +/− 0.08 vs. 1.11 +/− 0.25 p < 0.50) were inversely associated with CAD. Serum levels of copper and iron were significantly higher and plasma levels of antioxidant vitamins A, E and C and beta-carotene were significantly lower in patients with CAD compared to the rest of the subjects. In both rural (7.1 +/− 1.2 mg/day) and urban subjects (8.6 +/− 1.6 mg/day), zinc consumption was half of the recommended dietary allowances. Higher prevalence of CAD in urban compared to rural subjects was attributed to higher dietary fat intake and higher prevalence of risk factors in urban subjects.The findings suggest that lower serum levels of zinc and magnesium and lower zinc copper ratio were inversely associated with CAD. It is possible that urban populations with higher risk of CAD may benefit by decreasing dietary fat intake and by increasing their intake of foods rich in zinc and magnesium.

Diet, Antioxidants and Risk of Cancer: A Case-control Study

A total of 3810 patients were seen in hospital over a 2-year period. There were 101 patients with cancer of various organs of the body. These 101 cancer patients were compared with 100 age- and sex-matched control subjects selected from the same population. The aim was to ® nd the relation between dietary and plasma levels of antioxidants and minerals and the risk of cancer. Dietary intakes were assessed by a 7-day food intake assisted questionnaire to ® nd out previous intakes. The study showed that the plasma levels of antioxidant vitamins A, E and C and b -carotene and the zinc; copper ratio and zinc levels were signi® cantly and inversely associated with the cancer group compared to the control subjects. The serum calcium level was also lower in the cancer group but the magnesium level was higher. Underlying these ® ndings, the consumption of antioxidant vitamins A, E and C and b -carotene, calcium and magnesium was signi® cantly lower in the cancer group compared to the control subjects. The differences in intake indicated a higher risk of cancer with a lower consumption of antioxidant vitamins and fruit and vegetables and with a higher

Determinants of plasma anti-oxidant vitamin levels in a population at high risk for stomach cancer

Our objective was to identify the determinants of plasma levels of anti-oxidant vitamins which have been linked with decreased risk of cancer and other chronic diseases. Correlation analyses were performed between baseline plasma levels of ascorbic acid, alpha- and beta-carotenes, cryptoxanthin, lycopene and alpha- and gamma-tocopherols and baseline information on dietary and other demographic and life-style factors among 1,364 subjects 35-69 years of age, who are participants in a chemoprevention trial on pre-cancerous lesions of the stomach in Venezuela. Males had lower levels of ascorbic acid, alpha- and beta-carotene and cryptoxanthin and higher levels of alpha-tocopherol than females. This finding was confirmed in non-smokers and non-drinkers. In females, but not in males, age was positively associated with levels of ascorbic acid, cryptoxanthin, alpha- and beta-carotene and gamma-tocopherol. Male tobacco users had lower plasma levels of ascorbic acid, alpha- and beta-carotene and cryptoxanthin than nonusers, and regular alcohol drinkers had a decreased plasma levels of beta-carotene compared with non-drinkers. Female tobacco users had lower levels of ascorbic acid and cryptoxanthin than non-users, and regular alcohol drinkers had lower levels of ascorbic acid and lycopene than non-drinkers. Frequencies of consumption of fresh fruits, fruit juice, raw vegetables and plantains showed weak positive associations with plasma levels of several vitamins studied in both sexes. Sex, age in females, tobacco and alcohol use and dietary consumption affected plasma anti-oxidant vitamin levels in this population significantly. These factors may influence the effect of anti-oxidant treatment in intervention trials.

Dietary intake, plasma levels of antioxidant vitamins, and oxidative stress in relation to coronary artery disease in elderly subjects

The prevalence of coronary artery disease (CAD) in the urban population of India is similar to that in developed countries; Indian immigrants in industrialized countries have the highest prevalence of CAD. This is a cross-sectional survey within a random sample of a single urban setting in India. The relation between risk of CAD and plasma levels of vitamins A, C, E, and betacarotene was examined in 72 of 595 elderly subjects (12.1%) with CAD (aged 50 to 84 years). Plasma levels of vitamins A, C, E, and beta-carotene were significantly related to risk of CAD. Smoking (n = 145) and diabetes (n = 70) were the confounding factors. Lipid peroxides were higher in patients with CAD and diabetes, and in those who smoked. The inverse relation between CAD and low plasma vitamin C was substantially reduced after adjustment for smoking and diabetes. Vitamin A and E levels remained independently and inversely related to the risk of CAD after adjustment for age, smoking, diabetes, blood pressure, blood lipoproteins, and relative weight and body mass index. The adjusted odds ratios for CAD between the lowest and highest quintiles of vitamin E levels were 2.53 (95% confidence interval [CI] 1.11 to 5.31), vitamin C, 2.21 (95% CI 1.12 to 3.15), and beta-carotene, 1.72 (95% CI 0.88 to 3.62). The fatty acid composition of the diet, blood lipid levels, central obesity (waist-hip ratio),smoking habits, blood pressure, and plasma insulin levels do not appear to account for high rates of CAD among elderly Indians. The findings suggest that some elderly Indian populations with high rates of CAD can benefit from eating foods rich in antioxidant vitamins A, C, E, and beta-carotene. However, a reduction in vitamin levels may be due to changes in diet and lifestyle after diagnosis of CAD; therefore, more studies are necessary to confirm our findings.