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The Effect of Combined Vitamin C and Vitamin E Supplementation on Oxidative Stress Markers in Women with Endometriosis: A Randomized, Triple-Blind Placebo-Controlled Clinical Trial.
Amini, L, Chekini, R, Nateghi, MR, Haghani, H, Jamialahmadi, T, Sathyapalan, T, Sahebkar, A
Pain research & management. 2021;2021:5529741
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Endometriosis (EMS) is a chronic and estrogen-dependent pelvic inflammatory disease that arises from ectopic endometrial implantation and growth outside the uterus cavity. Oxidative stress, an imbalance between reactive oxygen spices and biological antioxidants, could play a key role in EMS pathophysiology. The aim of this study was to evaluate the effect of vitamin C and vitamin E coadministration on oxidative stress (OS) markers as well as pain severity in women with endometriosis. This study is a randomized placebo-controlled clinical trial on 60 reproductive-aged (15–45 years) women with pelvic pain and 1–3 stages of laparoscopic-proven endometriosis. The participants, researchers, and statistician were blind about the groups. The participants were randomly assigned to two groups by the simple randomization method: group A - intervention (n = 30) or group B - palcebo (n = 30). Results show that supplementation with vitamin C and vitamin E effectively reduces systemic OS indices in women with endometriosis. Authors conclude that their findings further support the potential role of antioxidants in the management of EMS.
Abstract
Background: Endometriosis is a chronic and estrogen-dependent pelvic inflammatory disease, which may have various causes, such as oxidative stress. Dysmenorrhea, dyspareunia, and pelvic pain are well-known symptoms of endometriosis. The present clinical trial assessed the role of supplementation with antioxidant vitamins on the indices of oxidative stress as well as the severity of pain in women with endometriosis. Materials and Methods: We enrolled 60 reproductive-aged (15-45 years) women with pelvic pain in this triple-blind clinical trial. They had 1-3 stages of laparoscopic-proven endometriosis. The participants were randomized to group A (n = 30), given vitamin C (1000 mg/day, 2 tablets of 500 mg each) and vitamin E (800 IU/day, 2 tablets of 400 IU each) combination, or group B (n = 30), given placebo pills daily for 8 weeks. Results: Following treatment with vitamin C and vitamin E, we found a significant reduction in MDA and ROS compared with the placebo group. There was no significant decline in total antioxidant capacity after treatment. However, the severity of pelvic pain (p value <0.001), dysmenorrhea (p value <0.001), and dyspareunia (p value <0.001) significantly decreased in the treatment group after 8 weeks of supplementation. Conclusions: The present findings support the potential role of antioxidants in the management of endometriosis. The intake of vitamin C and vitamin E supplements effectively reduced dysmenorrhea severity and improved dyspareunia and severity of pelvic pain.
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Selenium, antioxidants, cardiovascular disease, and all-cause mortality: a systematic review and meta-analysis of randomized controlled trials.
Jenkins, DJA, Kitts, D, Giovannucci, EL, Sahye-Pudaruth, S, Paquette, M, Blanco Mejia, S, Patel, D, Kavanagh, M, Tsirakis, T, Kendall, CWC, et al
The American journal of clinical nutrition. 2020;112(6):1642-1652
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Oxidative damage is a shared characteristic in chronic diseases such as cardiovascular disease (CVD), diabetes, cancer and ageing. Antioxidants mitigate the impact of oxidants and have been widely investigated in ageing and disease. However, the evidence for supplementary antioxidants has been mixed and some authorities have advised against the use of certain single nutrients for the prevention of CVD or cancer. This systematic review and meta-analysis focused on selenium due to its vital role in the antioxidant system and associations of low selenium blood levels with increased risk of CVD, cancers and death. The study included 43 randomised controlled trials (RCTs) evaluating the effect of supplemental selenium and antioxidants with or without selenium and their impact on CVD risk, cancer and all-cause mortality. Overall supplemental selenium or antioxidants alone did not seem to be associated with CVD outcomes, cancer, CVD and cancer mortality, or all-cause mortality. On close examination, a decreased risk was seen for CVD mortality when antioxidants were combined with selenium, whilst antioxidant mixtures without selenium demonstrated an increased risk in all-cause mortality. The findings did not seem to be influenced by dietary selenium intake. The authors suggested that inclusion of selenium as part of an antioxidant mix could be key for an antioxidant associated risk reduction. However, in the absence of further long term studies, a balanced antioxidant-rich diet was advocated as the safest approach. In clinical practice, where antioxidant support beyond diet is warranted, supplemental antioxidant use should be concurrent with adequate selenium supplementation, with dose benefits of 50-200mcg observed.
Abstract
BACKGROUND Antioxidants have been promoted for cardiovascular disease (CVD) risk reduction and for the prevention of cancer. Our preliminary analysis suggested that only when selenium was present were antioxidant mixtures associated with reduced all-cause mortality. OBJECTIVE We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to determine the effect of selenium supplementation alone and of antioxidant mixtures with or without selenium on the risk of CVD, cancer, and mortality. METHODS We identified studies using the Cochrane Library, Medline, and Embase for potential CVD outcomes, cancer, and all-cause mortality following selenium supplementation alone or after antioxidant supplement mixtures with and without selenium up to June 5, 2020. RCTs of ≥24 wk were included and data were analyzed using random-effects models and classified by the Grading of Recommendations, Assessment, Development, and Evaluation approach. RESULTS The meta-analysis identified 9423 studies, of which 43 were used in the final analysis. Overall, no association of selenium alone or antioxidants was seen with CVD and all-cause mortality. However, a decreased risk with antioxidant mixtures was seen for CVD mortality when selenium was part of the mix (RR: 0.77; 95% CI: 0.62, 0.97; P = 0.02), with no association when selenium was absent. Similarly, when selenium was part of the antioxidant mixture, a decreased risk was seen for all-cause mortality (RR: 0.90; 95% CI: 0.82, 0.98; P = 0.02) as opposed to an increased risk when selenium was absent (RR: 1.09; 95% CI: 1.04, 1.13; P = 0.0002). CONCLUSION The addition of selenium should be considered for supplements containing antioxidant mixtures if they are to be associated with CVD and all-cause mortality risk reduction. This trial was registered at https://www.crd.york.ac.uk/PROSPERO/ as CRD42019138268.
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Behaviour change, weight loss and remission of Type 2 diabetes: a community-based prospective cohort study.
Dambha-Miller, H, Day, AJ, Strelitz, J, Irving, G, Griffin, SJ
Diabetic medicine : a journal of the British Diabetic Association. 2020;37(4):681-688
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Type 2 Diabetes is considered a lifelong condition, but calorie restriction or weight loss can lead to complete remission. Patients newly diagnosed with Type 2 Diabetic may benefit from behavioural change over the long run. When Type 2 Diabetes is diagnosed early in the disease trajectory, it may increase the patient's motivation and make them more receptive to weight-loss interventions. This prospective cohort study included 865 newly diagnosed Type 2 diabetic patients from the ADDICTION Cambridge Trial, a pragmatic, parallel-group cluster randomised controlled trial. The study assessed the relationship between behaviour change and weight loss and the prospect of type 2 diabetes remission in the first year, following four years and after five years without intense dietary or lifestyle intervention in patients. 30% of the patients achieved diabetes remission at 5-year follow-up, with a significant likelihood of remission among those who achieved ≥ 10% weight loss in the first year of diagnosis. A self-reported change in intake of alcohol units was found to be the only consistent association between behaviour change and remission in this study. The role of behaviour change in the remission of diabetes requires further robust research. This study will help healthcare professionals understand the association between weight loss and remission in diabetic patients.
Abstract
AIM: To quantify the association between behaviour change and weight loss after diagnosis of Type 2 diabetes, and the likelihood of remission of diabetes at 5-year follow-up. METHOD We conducted a prospective cohort study in 867 people with newly diagnosed diabetes aged 40-69 years from the ADDITION-Cambridge trial. Participants were identified via stepwise screening between 2002 and 2006, and underwent assessment of weight change, physical activity (EPAQ2 questionnaire), diet (plasma vitamin C and self-report), and alcohol consumption (self-report) at baseline and 1 year after diagnosis. Remission was examined at 5 years after diabetes diagnosis via HbA1c level. We constructed log binomial regression models to quantify the association between change in behaviour and weight over both the first year after diagnosis and the subsequent 1-5 years, as well as remission at 5-year follow-up. RESULTS Diabetes remission was achieved in 257 participants (30%) at 5-year follow-up. Compared with people who maintained the same weight, those who achieved ≥ 10% weight loss in the first year after diagnosis had a significantly higher likelihood of remission [risk ratio 1.77 (95% CI 1.32 to 2.38; p<0.01)]. In the subsequent 1-5 years, achieving ≥10% weight loss was also associated with remission [risk ratio 2.43 (95% CI 1.78 to 3.31); p<0.01]. CONCLUSION In a population-based sample of adults with screen-detected Type 2 diabetes, weight loss of ≥10% early in the disease trajectory was associated with a doubling of the likelihood of remission at 5 years. This was achieved without intensive lifestyle interventions or extreme calorie restrictions. Greater attention should be paid to enabling people to achieve weight loss following diagnosis of Type 2 diabetes.
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Associations between maternal antioxidant intakes in pregnancy and infant allergic outcomes.
West, CE, Dunstan, J, McCarthy, S, Metcalfe, J, D'Vaz, N, Meldrum, S, Oddy, WH, Tulic, MK, Prescott, SL
Nutrients. 2012;4(11):1747-58
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This research studied the maternal intake of antioxidants (carotene, vitamin C, vitamin E, copper and zinc) during pregnancy and the effect on allergic outcomes during early infancy (eczema, food allergies, allergic sensitisation and wheeze) at 1 year of age. The study included 300 mother and child pairs from a pregnancy cohort in Western Australia from 2005 to 2008. The pregnant women had a family history of allergic rhinitis, asthma, eczema, food or other allergy. A post-natal randomised trial allocated either 650mg fish oil (280mg docosahexaenoic acid (DHA) and 110mg eicosapentaenoic acid (EPA)) or a placebo of olive oil for the first 6 months of life. The study also examined the effect of maternal diet during pregnancy. Demographic information was collected, and a semi quantitative food frequency questionnaire covering 212 foods was completed during the final trimester of pregnancy. Clinical outcome measures of the infants were taken at 12 months of age via a detailed history and examination. Eczema, IgE mediated food allergies and allergic sensitisation were the most common clinical outcomes of the study. The majority of pregnant women met the recommended daily intakes of antioxidants apart from vitamin E and zinc. At 12 months of age there was no difference in the occurrence of clinical outcomes between the fish oil and placebo groups. Higher dietary vitamin C in the mothers was associated with reduced risk of any diagnosed allergic disease when children were a year old, and also a reduced risk of wheeze. Higher copper intake was related to reduced risk of wheeze and development of early allergic disease. However, this was only seen in relation to nutrients from food rather than supplements. It was noted that there were no significant associations between early allergic responses/disease and dietary intake of carotene, vitamin E and zinc. In the group studied, the majority of mothers used some vitamin/mineral supplementation during pregnancy. There was no statistically significant association between carotene, vitamin E and zinc intake in pregnancy and risk of developing any allergic disease. Women reported intakes of dietary vitamin C were above the daily recommended intake of 60mg, and authors noted that allergic outcomes were not affected by vitamin supplementation.
Abstract
Antioxidant intakes in pregnancy may influence fetal immune programming and the risk of allergic disease. We investigated associations between maternal intakes of β-carotene, vitamin C, vitamin E, copper and zinc, and infant allergic outcomes. Antioxidant intakes of pregnant women (n = 420) assessed prospectively by a food frequency questionnaire, were examined in relation to allergic outcomes at 1 year of age (n = 300). The main relationships with allergic outcomes were seen with dietary vitamin C and copper. Specifically, higher maternal dietary vitamin C intake was associated with a reduced risk of any diagnosed infant allergic disease and wheeze. After adjustment for potential confounders the relationship with wheeze remained statistically significant. There was also an inverse linear relationship between vitamin C and food allergy. Higher dietary copper intake was associated with reduced risk of eczema, wheeze and any allergic disease. The relationship with wheeze and any allergic disease remained statistically significant in multivariate analysis, and there was also an inverse linear relationship between copper and food allergy. However, these relationships were only seen for nutrients present in food. There were no relationships between β-carotene, vitamin E or zinc and any allergic outcomes. In summary, this study suggests that maternal diet of fresh foods rich in vitamin C is associated with reduced risk of infant wheeze, and that copper intake is associated with reduced risk of several allergic outcomes.
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Antioxidant supplementation and nasal inflammatory responses among young asthmatics exposed to high levels of ozone.
Sienra-Monge, JJ, Ramirez-Aguilar, M, Moreno-Macias, H, Reyes-Ruiz, NI, Del Río-Navarro, BE, Ruiz-Navarro, MX, Hatch, G, Crissman, K, Slade, R, Devlin, RB, et al
Clinical and experimental immunology. 2004;138(2):317-22
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Exposure to air pollution has been related to an increased occurrence and severity of asthma. In this double-blind, randomised trial, a group of asthmatic children in Mexico City were given either a daily supplement containing 250mg of vitamin C and 50mg of vitamin E, or a placebo pill, for 12 weeks. Scientists measured inflammatory markers in the nasal passages of the children after being exposed to air pollution. Children who received the vitamin supplement did not experience an increase in inflammation after being exposed to air pollution, whereas children given the placebo did. The authors concluded that supplementation with antioxidants such as vitamin C and vitamin E might decrease nasal inflammation in children with asthma who are exposed to air pollution.
Abstract
The inflammatory response to ozone in atopic asthma suggests that soluble mediators of inflammation are released in response to oxidant stress. Antioxidants may alleviate additional oxidative stress associated with photochemical oxidant pollution. This study investigates the impact of antioxidant supplementation on the nasal inflammatory response to ozone exposure in atopic asthmatic children. We conducted a randomized trial using a double-blinded design. Children with asthma (n = 117), residents of Mexico City, were given randomly a daily supplement of vitamins (50 mg/day of vitamin E and 250 mg/day of vitamin C) or placebo. Nasal lavages were performed three times during the 4-month follow-up and analysed for content of interleukin-6 (IL-6), IL-8, uric acid and glutathione (GSx). IL-6 levels in the nasal lavage were increased significantly in the placebo group after ozone exposure while no increase was observed in the supplement group. The difference in response to ozone exposure between the two groups was significant (P = 0.02). Results were similar for IL-8, but with no significant difference between the groups (P = 0.12). GSx decreased significantly in both groups. Uric acid decreased slightly in the placebo group. Our data suggest that vitamin C and E supplementation above the minimum dietary requirement in asthmatic children with a low intake of vitamin E might provide some protection against the nasal acute inflammatory response to ozone.
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Improved antioxidant and fatty acid status of patients with cystic fibrosis after antioxidant supplementation is linked to improved lung function.
Wood, LG, Fitzgerald, DA, Lee, AK, Garg, ML
The American journal of clinical nutrition. 2003;77(1):150-9
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Oxidative stress is elevated in patients with cystic fibrosis (CF). It has been hypothesised that supplementing with antioxidants reduces oxidative stress and therefore the rate of lung deterioration in CF patients. The aim of the study was to examine oxidative stress and antioxidant defences in CF patients after antioxidation supplementation in relation to fatty acid status, dietary intake and clinical status. Children with CF were given a high dose supplement containing 200mg vitamin E, 300mg vitamin C, 25mg beta-carotene, 90 micrograms selenium and 500 micrograms vitamin A for 8 weeks. The control group received low doses of vitamins A and E equal to the RDA, which is part of routine treatment for some CF patients. At the end of the study, the group taking the high dose antioxidant supplement showed significant increases in plasma concentrations of vitamin E, beta-carotene, selenium and glutathione peroxidase compared to the control group. Despite this, there were no significant differences in markers of lung function or wellbeing between the two groups. The researchers did however find correlations between both increased plasma fatty acids and antioxidant (beta-carotene and selenium) status and improved lung function, suggesting that antioxidant supplementation and high fat diets may be beneficial for CF patients. Since increased plasma fatty acids are linked to oxidative stress, the authors point out the importance of reducing oxidative stress in CF patients who are on a high-fat diet.
Abstract
BACKGROUND Oxidative stress, as measured by 8-iso-prostaglandin F(2)(alpha) (8-iso-PGF(2)(alpha)), and depleted antioxidant defenses were shown in stable cystic fibrosis (CF) patients. The plasma fatty acid status of CF patients was linked to oxidative stress after respiratory exacerbations. OBJECTIVE We examined changes in plasma 8-iso-PGF(2)(alpha), antioxidant defenses, plasma fatty acid status, and clinical markers resulting from short-term antioxidant supplementation. DESIGN Forty-six CF patients were randomly assigned to either group A [low dose of supplement (10 mg vitamin E and 500 micro g vitamin A)] or group B [high dose of supplement (200 mg vitamin E, 300 mg vitamin C, 25 mg beta-carotene, 90 micro g Se, and 500 micro g vitamin A)]. Plasma concentrations of 8-iso-PGF(2)(alpha), vitamins E and C, beta-carotene, zinc, selenium, and copper; plasma fatty acid composition; erythrocyte glutathione peroxidase (EC 1.11.1.9) and superoxide dismutase (EC 1.15.1.1) activities; lung function; and dietary intake were measured before and after 8 wk of supplementation. RESULTS Antioxidant defenses in group B improved, whereas those in group A did not: in groups B and A, the mean (+/- SEM) changes (Delta) in vitamin E were 10.6 +/- 1.5 and -1.9 +/- 0.9 micro mol/L, respectively (P < 0.001), (Delta)beta-carotene were 0.1 +/- 0.04 and -0.01 +/- 0.02 micro mol/L, respectively (P = 0.007), (Delta)selenium were 0.51 +/- 0.10 and -0.09 +/- 0.04 micro mol/L, respectively (P < 0.001), and (Delta)glutathione peroxidase activity were 1.3 +/- 0.3 and -0.3 +/- 0.6 U/g hemoglobin, respectively (P = 0.016). There were no significant differences between the groups in Delta8-iso-PGF(2)(alpha), (Delta)vitamin C, (Delta)fatty acid composition, (Delta)superoxide dismutase activity, (Delta)lung function, or (Delta)white cell count. Within group B, (Delta)beta-carotene correlated with (Delta)percentage of forced vital capacity (r = 0.586, P = 0.005), (Delta)selenium correlated with (Delta)percentage of forced expiratory volume in 1 s (r = 0.440, P = 0.046), and (Delta)plasma fatty acid concentrations correlated with (Delta)percentage of forced expiratory volume in 1 s (r = 0.583, P = 0.006) and Delta8-iso-PGF(2)(alpha) (r = 0.538, P = 0.010). CONCLUSIONS Whereas increased beta-carotene, selenium, and fatty acid concentrations are linked to improved lung function, increased plasma fatty acid concentrations are linked to oxidative stress. If oxidative stress is deemed to be important to the clinical outcome of CF patients, means of reducing oxidative stress while maintaining a high-fat, high-energy diet must be investigated.
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Functional biochemical and nutrient indices in frail elderly people are partly affected by dietary supplements but not by exercise.
de Jong, N, Chin A Paw, MJ, de Groot, LC, de Graaf, C, Kok, FJ, van Staveren, WA
The Journal of nutrition. 1999;129(11):2028-36
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Elderly people are at risk of nutritional deficiencies for a variety of reasons including reduced appetite, increased medication, and alterations in the absorption and metabolism of vitamins and minerals with age. The aim of this study was to measure the influence of exercise, and supplementing the diet with vitamins and minerals, on indicators of nutritional and health status in frail elderly people. A 17-week randomised controlled trial was carried out on 145 frail elderly people living in the community. Participants were given either; 1) food products enriched with vitamins D, E, thiamine, riboflavin, B6, folic acid, B12, calcium, magnesium, zinc, iron and iodine; 2) an exercise programme; 3) both enriched food products and exercise programme; or 4) food products that had not been enriched and a social programme (the control group). At the end of the study, significant improvements in the blood levels of vitamins B6, B12, C and D were detected in the groups receiving the enriched food products compared to the controls. There was no additional benefit to be gained from exercise. The improvement in nutritional status did not appear to influence several other biological indicators of health, perhaps because these indicators were already within normal levels at the start of the study. Despite this, the authors concluded that long-term supplementation may help to maintain optimal vitamin and mineral levels in elderly people, and therefore reduce the chance of this population developing health problems related to malnutrition.
Abstract
A decline in dietary intake due to inactivity and, consequently, development of a suboptimal nutritional status is a major problem in frail elderly people. However, benefits of micronutrient supplementation, all-round physical exercise or a combination of both on functional biochemical and hematologic indicators of nutritional and health status in frail elderly subjects have not been tested thoroughly. A 17-wk randomized controlled trial was performed in 145 free-living frail elderly people (43 men, 102 women, mean age, 78 +/- 5.7 y). Based on a 2 x 2 factorial design, subjects were assigned to one of the following: 1) nutrient-dense foods, 2) exercise, 3) both (1) and (2) or 4) a control group. Foods were enriched with micronutrients, frequently characterized as deficient [25-100% of the recommended daily allowance (RDA)] in elderly people. Exercises focused on skill training, including strength, endurance, coordination and flexibility. Dietary intake, blood vitamin levels and nutritional and health indicators, including (pre)albumin, ferritin, transferrin, C-reactive protein, hemoglobin and lymphocytes were measured. At baseline, 28% of the total population had an energy intake below 6.3 MJ, up to a maximum of 93% having vitamin intakes below two thirds of the Dutch RDA. Individual deficiencies in blood at baseline ranged from 3% for erythrocyte glutathione reductase-alpha to 39% for 25-hydroxy vitamin D and 42% for vitamin B-12. These were corrected after 17 wk in the two groups receiving the nutrient-dense foods, whereas no significant changes were observed in the control or exercise group. Biochemical and hematologic indicators at baseline were within the reference ranges (mean albumin, 46 g/L; prealbumin, 0.25 g/L; hemoglobin, 8.6 mmol/L) and were not affected by any of the interventions. The long-term protective effects of nutrient supplementation and exercise, by maintaining optimal nutrient levels and thereby reducing the initial chance of developing critical biochemical values, require further investigation. Other indicative functional variables for suboptimal nutritional status, in addition to those currently selected, should also be explored.