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To determine whether dietary modification rather than use of supplements can raise indices of vitamin E status to potentially cardioprotective levels.
Eight week randomised controlled trial with parallel treatments to compare increased use of vitamin E-rich foods, supplementation with 200 IU of vitamin E, and a placebo.
Dunedin, New Zealand.
Ninety...
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Context 1
... total cholesterol and plasma alpha tocopherol concentrations at baseline were signi®cantly correlated (Figure 1). At baseline dietary vitamin E intake was not correlated with plasma alpha tocopherol concentrations (Figure 2). Analysis of the diet and placebo groups alone ( Figure 3) showed a signi®cant correlation between change in dietary vitamin E and change in plasma alpha tocopherol (r 0.28, P 0.027). Change in dietary vitamin E was not correlated with change in plasma alpha tocopherolacholes- terol (r 0.19, P ...
Citations
... If through diet, the daily required amount of different nutrients is not met, different processed food, and fortified with different nutrients can be approached to ensure a healthy lifestyle. Literature studies found a significant role of some food nutrients to tackle a few harmful RNA viruses including SARS viruses through boosting up immunity, and these were presented meticulously in the Table 2 [114,115,116,117,118,119,120,121,122]. ...
The novel coronavirus disease 2019 (COVID-19) has unfolded an unprecedented worldwide public health emergency with disastrous economic consequences. Around 96 million coronavirus cases have already been identified with over half a million deaths. Despite numerous efforts by the government as well as international organizations, these numbers are still increasing with a surprising rate. Although urgent and absolutely necessary, a reliable therapeutic or vaccine is still elusive and this status quo may remain for an uncertain period of time. Taken that into account, boosting up adaptive immunity through nutritional interventions may help subside this epidemic and save many lives. This review focuses on the nexus between a balanced diet and adaptive immunity, particularly, how a poor diet may lead to compromised immunity resulting in susceptibility to viral infections. Additionally, we discuss how nutrients (vitamins, minerals, trace elements) can be used as a tool to modulate immune response and thus impede viral infections. The study also summarizes nutritional recommendations to combat COVID-19 in different countries and territories as well as dietary sources of those key nutrients. Moreover, different nutritional intervention strategies based on different age groups, physiological and medical conditions were also included, and the challenges of nutritional interventions towards the care of COVID-19 patients are also discussed. Since the availability of a drug or vaccine is still uncertain, a balanced diet or nutrient therapy can be used as a robust strategy to combat COVID-19. Thus, we hope this review may help to make an informed decision with regard to diet choice both at individual level as well as clinical settings.
Keywords
MacronutrientsMicronutrientsCOVID-19SARS-CoV-2ImmunityComplicationsNutritionViral infection
... Time points calculated as a proportion of the overall study length indicated that the commencement of the study was the most commonly used time point (57.5%, n=61) for dietary assessment. The second assessment was more likely to be at the midpoint of the study (32.3%, n=32) (Armstrong et al., 2000, Sebedio et al., 2000, Ashley et al., 2007, Barnard et al., 2009, Barnard et al., 2006, Bhargava et al., 2004, Chee et al., 2003, Chen et al., 2006, Davidson et al., 2001, Davis et al., 2009, Donaghue et al., 2000, Drummond et al., 2003, Dyerberg et al., 2004, He et al., 2004, Hendriks et al., 2003, Hermansen et al., 2005, Iyer et al., 2006, Maki et al., 2002, Marfella et al., 2006, Maskarinec et al., 2004a, Maskarinec et al., 2004b, McGavin et al., 2001, Moeller et al., 2003, Mori et al., 2004, Murphy et al., 2007, Riddell et al., 2000, Shah et al., 2002, Shah et al., 2004, Sloth et al., 2004, Smith-Warner et al., 2000, Sondergaard et al., 2003, Tapsell et al., 2004, Turner-McGrievy et al., 2008, Waller et al., 2004, Leslie et al., 2002 with 25 studies completing their dietary assessments in only two periods of assessment of which only 11 included the endpoint of the study as the final time point. (Barr et al., 2000, Conceicao de Oliveira et al., 2003, Erlund et al., 2003, Griffin et al., 2006, Haub et al., 2005, Pins et al., 2002, Scholtz et al., 2004, Spiller et al., 2003, Takatsuka et al., 2000, Thompson et al., 2005b, Wilkinson et al., 2005 The third and fourth time points were the most common times for a final assessment with 41.3% (n=31) (Ammerman et al., 2003, Keyserling et al., 1999, Armstrong et al., 2000, Sebedio et al., 2000, Barnard et al., 2009, Barnard et al., 2006, Bhargava et al., 2004 Critical Reviews in Food Science and Nutrition ACCEPTED MANUSCRIPT ACCEPTED MANUSCRIPT 9 et al., 2003, Davidson et al., 2001, Davis et al., 2009, Djuric et al., 2003, Djuric et al., 2004, Djuric et al., 1999a, Donaghue et al., 2000, Drummond et al., 2003, Dyerberg et al., 2004, Haub et al., 2002, He et al., 2004, Hermansen et al., 2005, Iyer et al., 2006, Jacobs et al., 2002, Alberts et al., 2000, Maki et al., 2002, McGavin et al., 2001, Moeller et al., 2003, Murphy et al., 2007, Riddell et al., 2000, Shah et al., 2002, Shah et al., 2004, Sloth et al., 2004, Swain et al., 2002, Tapsell et al., 2004, Turner-McGrievy et al., 2008, Van Horn et al., 2001, Leslie et al., 2002 and 40.5% (n=17) (Chen et al., 2006, Due et al., 2004, Ebbeling et al., 2005, Greenberg et al., 2009, Hawkes et al., 2009, Heath et al., 2001, Hendriks et al., 2003, Jen et al., 2004, Jensen et al., 2002, Ma et al., 2005, Metz et al., 2000, Mori et al., 2004, Rolls et al., 2005, Smith-Warner et al., 2000, Sondergaard et al., 2003, West and de Looy, 2001 of studies, respectively opting for this approach. ...
The importance of monitoring dietary intake within a randomized controlled trial becomes vital to justification of the study outcomes when the study is food-based. A systematic literature review was conducted to determine how dietary assessment methods used to monitor dietary intake are reported and whether assisted technologies are used in conducting such assessments. OVID and ScienceDirect databases 2000-2010 were searched for food-based, parallel, randomized controlled trials conducted with humans using the search terms "clinical trial", "diet$ intervention" AND "diet$ assessment", "diet$ method$", "intake", "diet history", "food record", "food frequency questionnaire", "FFQ", "food diary", "24 hour recall". A total of 1364 abstracts were reviewed and 243 studies identified. The size of the study and country of origin appear to be the two most common predictors of reporting both the dietary assessment method and details of the form of assessment. The journal in which the study is published has no impact. Information technology use may increase in the future allowing other methods and forms of dietary assessment to be used efficiently.
... al., 2008). However, effects of AT on endothelial dysfunction induced by TNF-α in HAEC are not well documented.Some of the foods with high AT content, and the bioavailability of this form of vitamin E is highest, are ground hazelnuts, canola-based margarine, wheatgerm oil and other vitamin E-rich foods such as avocado and pumpkin(McGavin JK et al., 2001).Whole blood is a biofluid containing RBC. It has active metabolism, mainly the glycolytic or Krebs cycle, catalyzed by a range of enzymes. ...
The thesis addresses two major issues. Firstly: The study the effects of polyphenol-rich peanut extract and bioactive compounds (alpha-tocopherol) in cellular models of inflammation (monocytic cells; THP-1) and on endothelial dysfunction (human aortic endothelial cells; HAEC), respectively. Secondly: The optimisation of blood sampling for human studies to characterise the profile of aqueous and lipid metabolites, fatty acid composition, lipoprotein subclasses, and polyphenol content of plasma and red blood cells. Peanut extract exerts anti-inflammatory effects by inhibiting extracellular TNF-α protein via the inhibition of c-Jun transcription factor activation. Alpha-tocopherol improves endothelial function by inhibiting VCAM-1 and, to a lesser extent, E-selectin and ICAM-1. Analyses of metabolites in plasma and red blood cells generate complementary information. The measurements may need to be performed in either, or both, matrices, depending on the objectives of the study.
... Vitamin E in the multimicronutrient powder was found to remain stable after 30 minutes of cooking or 10 months of storage [89]. In a study of adults in New Zealand, supplementation with 200 IU/day of RRR-α-tocopherol was more effective at appreciably raising circulating concentrations after 8 weeks than a dietary modification aimed to achieve vitamin E intakes of 30 to 40 mg/day (45 to 60 IU/day), although both interventions led to a significant improvement in plasma α-tocopherol and α-tocopherol:cholesterol ratio by 6 weeks [91]. ...
... To our knowledge, no interventions aimed at dietary modification to improve vitamin E status have been carried out in developing countries to date. However, existing evidence suggests that increasing intakes of dietary sources of the vitamin improves vitamin E status [91,93], and it is feasible that such an intervention could be targeted at high-risk populations in developing countries. ...
In addition to its role as a potent antioxidant, vitamin E is involved in a wide range of physiological processes, ranging from immune function and control of inflammation to regulation of gene expression and cognitive performance. Results from multiple studies suggest that poor nutritional status and higher prevalence of other oxidative stressors such as malaria and HIV infection predispose populations in developing countries for vitamin E deficiency. Although direct comparison between study outcomes is complicated by varied definitions of vitamin E deficiency, data trends indicate that children and the elderly are more vulnerable age groups and that men may be at higher risk for deficiency than women. Public health initiatives aimed at improving the vitamin E status of high-risk populations in developing countries would be prudent to counteract oxidative stress, improve immune function, and protect against neurologic and cognitive deficits. Additional research is needed to establish dose-response relationships of various interventions and to develop cost-effective, culturally-appropriate, and targeted programs.
... This would be equivalent to marginal dietary vitamin E supply and about 1500 -2000 mg/d of vitamin E in a 70 kg human. The þa-Toc dose is not achievable with a normal diet, but it is considered within the range of high-dosage supplementation (22,32) . ...
The molecular basis of the positive association between apoE4 genotype and CVD remains unclear. There is direct in vitro evidence indicating that apoE4 is a poorer antioxidant relative to the apoE3 isoform, with some indirect in vivo evidence also available. Therefore it was hypothesised that apoE4 carriers may benefit from alpha-tocopherol (alpha-Toc) supplementation. Targeted replacement mice expressing the human apoE3 and apoE4 were fed with a diet poor (0 mg/kg diet) or rich (200 mg/kg diet) in alpha-Toc for 12 weeks. Neither apoE genotype nor dietary alpha-Toc exerted any effects on the antioxidant defence system, including glutathione, catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase activities. In addition, no differences were observed in mitogen-induced lymphocyte proliferation. alpha-Toc concentrations were modestly higher in plasma and lower in tissues of apoE4 compared with apoE3 mice, with the greatest differences evident in the lung, suggesting that an apoE4 genotype may reduce alpha-Toc delivery to tissues. A tendency towards increased plasma F2-isoprostanes in apoE4 mice was observed, while liver thiobarbituric acid-reactive substances did not differ between apoE3 and apoE4 mice. In addition, C-reactive protein (CRP) concentrations were reduced in apoE4 mice indicating that this positive effect on CRP may in part negate the increased CVD risk associated with an apoE4 genotype.
... Some studies have shown difficulty in getting appropriate AT plasma concentrations from foods [16]; and worse, many women do not consume vegetable oils and other vitamin E-rich food because its hypercaloric content is not attractive for modern weight control. In Mexico, the prevalence of AT deficiency among aged women was 30% according to the National Nutrition Survey in 1999, ENN, 1999 [17]. ...
Despite extensive research, the effects of alpha-tocopherol supplementation remain controversial. Few studies have been focused on obese and overweight people. We examined the effects of alpha-tocopherol (AT) on the oxidative status and metabolic profile in overweight women. Sixteen overweight women between the ages of 40-60 years old, received AT, 800 IU/day during 12 weeks, followed by a 6-week washout period. Blood samples were taken at the beginning and then every 6 weeks until the end of the study. AT, retinol, malondialdehyde (MDA), total antioxidant status (TAS), selenium-dependent glutathione peroxidase (GPx) and CuZn-superoxide dismutase (SOD) were quantified to evaluate the oxidative stress. The metabolic profile was estimated by measuring glycated hemoglobin (HbA1c) in erythrocytes and glucose, phosphate, magnesium, lipid and lipoprotein concentrations in serum. Under AT administration HbA1c, serum- MDA levels and erythrocyte GPx activity were markedly reduced. TAS, AT and Mg2+ concentrations in serum and SOD activity in erythrocytes were higher after AT treatment. Body weight; glucose, lipid and retinol concentrations, or blood cells count were unchanged. Lipid peroxidation was considerably reduced in AT treated women and also improved serum antioxidant status was observed, but the imbalanced response between erythrocyte SOD and GPx activities could affect normal response to oxidative stress.
... In a study on healthy subjects carried out by Zino et al (156), an average extra intake of 700g of fruit and vegetables per day resulted in raised levels of plasma antioxidants (vitamin C, αand β-carotene). Regarding vitamin E, McGavin et al (157) showed that an increased intake of vitamin E from, on average, 10 mg/day to 22 mg/day only resulted in a small increase in plasma α-tocopherol in healthy subjects. ...
... Plasma α-tocopherol was determined by reverse phase high performance liquid chromatography (HPLC) with UV detection using a modification of a method described by Kock et al., (1997). There is a strong relationship between plasma cholesterol and α-tocopherol levels (McGavin et al., 2001), thus all results presented are expressed as cholesterol standardised α-tocopherol (μmol α-tocopherol / mmol total cholesterol). Dietary intake was assessed by a dietitian using a narrative diet history (Tapsell et al., 1999). ...
Levels of vitamin E have been reported to be lower in patients suffering major depression, but whether this is due to inadequate dietary intake or the pathophysiology of depression is not known, and was the subject of the present study.
Wollongong, Australia.
Plasma vitamin E (alpha-tocopherol) was measured in 49 adults with major depression, age (mean+/-s.d.): 47+/-12 y. In a subset (n=19) usual dietary intake of vitamin E was determined by diet history.
Subjects had significantly lower plasma alpha-tocopherol (4.71+/-0.13 mumol/mmol cholesterol) than has previously been reported for healthy Australians, and plasma alpha-tocopherol was inversely related to depression score (by Beck Depression Inventory) (r=-0.367, P<0.009). Diet analysis indicated that 89% of subjects met or exceeded the recommended intake for vitamin E, and dietary intake was not related to plasma alpha-tocopherol level in this subset.
These findings suggest that plasma levels of alpha-tocopherol are lower in depression, but this is not likely to be the result of inability to meet recommended dietary intake. .
... In line with other studies, our findings support the oxidative stress hypothesis in dementia. Since previous studies have demonstrated that increasing intake of vitamins leads to an increase in plasma concentrations (Jacques et al, 1995;Kontush et al, 2001;McGavin et al, 2001), and even in cerebrospinal fluid levels (Kontush et al, 2001), the implication of our results could be the value of detecting subjects at higher risk of developing a dementia based on biological data (low vitamin E plasma concentration). Thus, vitamin E supplementation could be proposed to these subjects in order to help to prevent dementia, in addition to other modes of prevention. ...
To analyse the relation between antioxidant vitamins A, E, and malondialdehyde (MDA) lipoperoxidation product plasma concentrations with incident dementia.
: A nested case-control within the PAQUID (Personnes Agées QUID) cohort.
The PAQUID population-based prospective cohort in southwestern France.
Among 626 subjects with blood collection at baseline, 46 developed a dementia during the follow-up and were considered to be cases. Each case was matched (on age and sex) to three controls.
Plasma vitamin E concentrations were lower among cases (mean value at 22.62 micromol/l (s.d.: 7.38) vs 24.99 (s.d.: 6.73 among controls). The same trend was observed for vitamin A concentrations, but the difference was not significant. On the contrary, MDA concentrations tended to be higher (mean value 1.35 micromol/l (s.d.: 0.53) vs 1.23 (s.d.: 0.44)) among cases. In logistic regression models, plasma values were split into tertiles. Adjusted for confounders, the risk of dementia was significantly increased in the lowest vitamin E tertile (< or =21.0 micromol/l) (OR=3.12, P=0.033) compared to the highest one (> or =25.5 micromol/l). The risk of Alzheimer's disease was also increased, with borderline significance (OR=3.06, P=0.053). Risks associated with vitamin A were nonsignificant. Similarly, there was a trend to an increased risk of dementia in the highest tertile of MDA (OR=1.67, P=0.31).
These results suggest that subjects with low plasma vitamin E concentrations are at a higher risk of developing a dementia in subsequent years.
... Interestingly, these changes were seen within the first two weeks of intervention, indicating that the plasma antioxidants in question respond quite fast to changes in dietary intake of antioxidants. In contrast, the levels of tocopherols may be more difficult to elevate by means of increasing the intake of vitamin E-rich foods [29]. In healthy individuals the plasma levels of antioxidants may be affected by many factors other than the nutrient intake, such as the degree of absorption, intake of other nutrients, homeostatic regulation etc. ...
... In the study on healthy subjects by Zino et al [28], an average extra intake of 700 g of fruit and vegetables per day resulted in raised levels of plasma antioxidants (vitamin C, α-and β-carotene). Regarding vitamin E, McGavin et al showed that an increased intake of vitamin E from, on average, 10 mg/day to 22 mg/day only resulted in a small increase in plasma α-tocopherol in healthy subjects [29]. For patients with RA the required amount could be even higher due to the impact of the disease. ...
Previously we have reported that patients with rheumatoid arthritis (RA) obtained a significant reduction in disease activity by adopting a Mediterranean-type diet. The present study was carried out to investigate the antioxidant intake, the plasma levels of antioxidants and a marker of oxidative stress (malondialdehyde) during the study presented earlier.
RA patients randomized to either a Mediterranean type diet (MD group; n = 26) or a control diet (CD group; n = 25) were compared during a three month dietary intervention study. Their antioxidant intake was assessed by means of diet history interviews and their intake of antioxidant-rich foods by a self-administered questionnaire. The plasma levels of retinol, antioxidants (alpha- and gamma-tocopherol, beta-carotene, lycopene, vitamin C and uric acid) and urinary malondialdehyde (MDA), a marker for oxidative stress, were determined using high performance liquid chromatography. The Student's t-test for independent samples and paired samples were used to test differences between and within groups. For variables with skewed distributions Mann-Whitney U-test and Wilcoxon signed ranks test were performed. To evaluate associations between dietary intake of antioxidants, as well as between disease activity, MDA and antioxidants we used Pearson's product moment correlation or Spearman's rank correlation.
The MD group had significantly higher intake frequencies of antioxidant-rich foods, and also higher intakes of vitamin C (p = 0.014), vitamin E (p = 0.007) and selenium (p = 0.004), and a lower intake of retinol (p = 0.049), compared to the CD group. However, the difference between the groups regarding vitamin C intake was not significant when under- and over-reporters were excluded (p = 0.066). There were no changes in urine MDA or in the plasma levels of antioxidants (after p-lipid adjustments of the tocopherol results), from baseline to the end of the study. The levels of retinol, vitamin C and uric acid were negatively correlated to disease activity variables. No correlation was found between antioxidant intake and the plasma levels of antioxidants.
Despite an increase in reported consumption of antioxidant-rich foods during the Mediterranean diet intervention, the levels of plasma antioxidants and urine MDA did not change. However, the plasma levels of vitamin C, retinol and uric acid were inversely correlated to variables related to RA disease activity.
