Diets high in total antioxidant capacity improve risk biomarkers of cardiovascular disease: a 9-month observational study among overweight/obese postmenopausal women

Dietary Total Antioxidant Capacity Can Modify the Effects of Apo-B Polymorphisms (Ins/Del and EcoRI) on Lipid Profiles and Atherogenic Indices Between Diabetic Patients

We aimed to study the role of Apolipoprotein B (Apo-B) polymorphisms (Ins/Del and EcoRI) and genotype interaction on lipid profiles and atherogenic indices in response to changes in dietary total antioxidant capacity (DTAC) of diet. This cross-sectional study consisted of 700 diabetic patients. Biochemical markers including total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglyceride (TG), superoxide dismutase (SOD), C-reactive protein (CRP), total antioxidant capacity (TAC), interlukin-18 (IL-18), and Prostaglandin F2α (PGF2α) were measured based on standard protocols. Genotyping of the Apo-B polymorphisms was conducted by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Subjects with Ins/Ins genotype with higher DTAC intake had lower TG, AIP, and AC compared to Del-allele carriers. Moreover, A-allele carriers (EcoRI) with a higher median intake of DTAC had lower body mass index (BMI) and waist circumference (WC) compared to GG homozygotes. For combined genotypes, the EcoRI only variant (Ins/Ins and AA + AG) with higher DTAC intake had lower BMI and WC. Moreover, Ins/Del only variant (Ins/del + del/del and GG) with more adherence to DTAC had higher TG and AIP. Our study showed that Apo-B polymorphisms interact with the antioxidant capacity of diet to ameliorate the risk of cardio-metabolic diseases, especially atherosclerosis in the A carriers of EcoR1 and Ins/Ins homozygous of Ins/Del polymorphism.

Association between the Composite Dietary Antioxidant Index and Atherosclerotic Cardiovascular Disease in Postmenopausal Women: A Cross-Sectional Study of NHANES Data, 2013-2018

The relationship between composite dietary antioxidant index (CDAI) levels and the risk of atherosclerotic cardiovascular disease (ASCVD) in postmenopausal women is unknown. In total, 3109 women from the National Health and Nutrition Examination Survey 2013-2018 were included in this cross-sectional study. We evaluated the association between CDAI levels and the risk of ASCVD by using three logistic regression models and restricted cubic splines. A stratified analysis and sensitivity analysis were also conducted. The restricted cubic splines exhibited an L-shaped dose-response association between CDAI levels and the ASCVD risk. Logistic regression analysis found that CDAI levels were negatively associated with the occurrence of ASCVD. The ORs associated with a per-SD increase in CDAI were 0.67 (95% CI: 0.51-0.88) for ASCVD risk. Similarly, women in the group with high CDAI levels were less likely to have ASCVD (OR = 0.71, 95% CI: 0.50-0.98) compared to those in the group with low CDAI levels. When the CDAI levels were divided into quartiles, it was found that the ORs for ASCVD with CDAI levels in Q2 (-1.04-1.11), Q3 (1.11-3.72), and Q4 (3.72-43.87) were 0.63 (0.44, 0.90), 0.64 (0.42, 0.94), and 0.51 (0.27, 0.97), respectively, compared to those with CDAI levels in Q1 (-6.83--1.04). In addition, age, high-density lipoprotein cholesterol levels, and smoking behaviors acted as potential modifiers, and ORs were more significant in women aged 40-69 years, in individuals with low high-density lipoprotein cholesterol levels, and in smokers (p for interaction <0.05). These findings may offer valuable insights into the role of CDAI levels in the development of ASCVD among postmenopausal women.

Dietary Total Antioxidant Capacity, a Diet Quality Index Predicting Mortality Risk in US Adults: Evidence from the NIH-AARP Diet and Health Study

Dietary total antioxidant capacity (TAC) is an index representing the total antioxidant power of antioxidants consumed via the diet. This study aimed to investigate the association between dietary TAC and mortality risk in the US adults using data from the NIH-AARP Diet and Health Study. A total of 468,733 adults aged 50-71 years were included. Dietary intake was assessed using a food frequency questionnaire. Dietary TAC from diet was calculated from antioxidants including vitamin C, vitamin E, carotenoids, and flavonoids, and TAC from dietary supplements was calculated from supplemental vitamin C, vitamin E, and beta-carotene. During a median follow-up of 23.1 years, 241,472 deaths were recorded. Dietary TAC was inversely associated with all-cause (hazard ratio (HR) for quintile 5 vs. quintile 1: 0.97, 95% confidence interval (CI): 0.96-0.99, p for trend < 0.0001) and cancer mortality (HR for quintile 5 vs. quintile 1: 0.93, 95% CI: 0.90-0.95, p for trend < 0.0001). However, dietary supplement TAC was inversely associated with cancer mortality risk only. These findings indicate that consuming a habitual diet high in antioxidants may reduce the risk of all-cause and cancer mortality and TAC from foods might confer greater health benefits than TAC from dietary supplements.

The Use of Infrared Spectroscopy for the Quantification of Bioactive Compounds in Food: A Review

Infrared spectroscopy (wavelengths ranging from 750-25,000 nm) offers a rapid means of assessing the chemical composition of a wide range of sample types, both for qualitative and quantitative analyses. Its use in the food industry has increased significantly over the past five decades and it is now an accepted analytical technique for the routine analysis of certain analytes. Furthermore, it is commonly used for routine screening and quality control purposes in numerous industry settings, albeit not typically for the analysis of bioactive compounds. Using the Scopus database, a systematic search of literature of the five years between 2016 and 2020 identified 45 studies using near-infrared and 17 studies using mid-infrared spectroscopy for the quantification of bioactive compounds in food products. The most common bioactive compounds assessed were polyphenols, anthocyanins, carotenoids and ascorbic acid. Numerous factors affect the accuracy of the developed model, including the analyte class and concentration, matrix type, instrument geometry, wavelength selection and spectral processing/pre-processing methods. Additionally, only a few studies were validated on independently sourced samples. Nevertheless, the results demonstrate some promise of infrared spectroscopy for the rapid estimation of a wide range of bioactive compounds in food matrices.

Dietary Antioxidant Capacity Indices are Negatively Correlated to LDL-Oxidation in Adults

INTRODUCTION

Former research studies have demonstrated controversial associations between dietary indices and oxidative stress biomarkers including oxidized low-density lipoprotein (ox-LDL) and malondialdehyde (MDA). So, in this cross-sectional study, we aimed to assess the association of dietary total antioxidant capacity (DTAC), oxidative balance score, and phytochemical index (PI) with ox-LDL/MDA in a healthy adult population of Shiraz, Iran.

METHODS

236 individuals participated in this cross-sectional study. DTAC, OBS, and PI were calculated using a 168-item food frequency questionnaire (FFQ), which was previously validated in Iran. We measured ox-LDL and MDA in blood samples of the participants using commercially existing kits. Crude and adjusted models of linear regression were used to evaluate the relation of dietary indices with ox-LDL and MDA.

RESULTS

There was a significant association between ox-LDL and DTAC in both crude (β = -1.55; 95% CI: -2.53, -0.58; P-trend = 0.002) and adjusted (β = -1.65 95% CI: -2.66, -0.64; P-trend = 0.001) models. Also, a negative association was observed between ox-LDL and PI in the crude (β = -1.26 95% CI: -2.33, -0.29; P-trend = 0.01) and adjusted (β = -1.36 95% CI: -2.38, -0.34; P-trend = 0.01) models.

CONCLUSION

Results of this study showed that DTAC and PI were inversely associated with ox-LDL as markers of lipid peroxidation. But no correlations were seen between MDA and dietary antioxidant indices.

Evaluation of the predictive value of different dietary antioxidant capacity assessment methods on healthy and unhealthy phenotype in overweight and obese women

Purpose

Predictive value of different dietary antioxidant capacity assessment methods on healthy and unhealthy phenotypes in overweight and obese women is still unclear. This study aimed to evaluate the predictive value of different dietary antioxidant capacity assessment methods on healthy and unhealthy phenotypes in overweight and obese women.

Methods

A total of 290 overweight and obese women were included in this cross-sectional study. Food intake was assessed using a semi-quantitative food frequency questionnaire (FFQ). Dietary antioxidant capacity was calculated using valid databases of antioxidant value. The receiver operating characteristic (ROC) curve method was used to evaluate the predictive value of antioxidant capacity indices, including dietary antioxidant quality score (DAQS), ferric reducing ability of plasma (FRAP), total reactive antioxidant potential (TRAP), and trolox equivalent antioxidant capacity (TEAC).

Results

The results showed that the highest area under the ROC curve for predicting metabolically healthy obesity (MHO) belongs to the TRAP method (area under the curve (AUC) = 0.53). In addition, this method had the highest AUC for predicting inflammatory marker of C-reactive protein (hs-CRP) (AUC = 0.54) and the index of the homeostatic model assessment for insulin resistance (HOMA-IR) (AUC = 0.59). The highest AUC for triglyceride prediction was related to the DAQS method (AUC = 0.56). Moreover, a significant correlation of FRAP (r = -0.15, P = 0.02), TRAP (r = -0.19, P < 0.001), TEAC (r = -0.18, P< 0.001) with HOMA-IR was reached.

Conclusion

The findings of this study show that the best way to predict the status of MHO is TRAP method. This method is also the best predictor of hs-CRP and HOMA-IR. DAQS method is the best predictor for TG.

Sagittaria trifolia tuber: bioconstituents, processing, products, and health benefits

Sagittaria trifolia is an aquatic plant that is distributed worldwide. The edible tuber part of S. trifolia is a very common and popular vegetable in China. The aim of the present review is to discuss the discovery of nutraceuticals from S. trifolia tuber by reviewing its major constituents, food processing, food products, and health-promoting benefits. Sagittaria trifolia tuber comprises a series of nutritional and bioactive constituents, including dietary fibers, amino acids, minerals, starches, non-starch polysaccharides, diterpenoids, colchicine, phenols, and organic acids. Food processing affects its flavor, biocomponents, and bioactivity. Numerous S. trifolia tuber-based food products and nutraceuticals have been developed, but new categories of products and the anticipated functions still need to be explored. The non-starch polysaccharides could be the central ingredients that contribute to the plant's antioxidant, hepatoprotective, hypoglycemic, lipid-regulating, and immunostimulatory properties. Of these, antioxidant and hepatoprotective effects have been thoroughly investigated. Procedures for the extraction and purification of polysaccharides influence their health-promoting actions. Overall, S. trifolia tuber is an underutilized aquatic vegetable species that is an emerging subject for nutraceutical research. © 2020 Society of Chemical Industry.

Anthropometric and Biochemical Measures in Bariatric Surgery Candidates: What Is the Role of Inflammatory Potential of Diet?

BACKGROUND

The present study aimed to assess dietary total antioxidant capacity (TAC), dietary phytochemical intake (PI), and dietary inflammatory index (DII) in patients with morbid obesity who are candidates of bariatric surgery and their association with anthropometric and biochemical parameters.

METHODS AND MATERIALS

One hundred seventy patients with morbid obesity who were referred to surgery clinic of Firoozgar Hospital were enrolled in the study. Ideal body weight and adjusted ideal body weight were calculated. The dietary data were collected using a food frequency questionnaire. Anthropometrics and biochemical parameters were assessed. A p-value of <0.05 was considered significant.

RESULTS

The strongest correlations of DII with dietary intakes and anthropometric and biochemical biomarkers were found for iron (p<0.0001). Significant association was also observed for ferritin (p=0.02) and transferrin (p=0.02). In terms of PI, The strongest associations were also found for iron (p<0.0001). Additionally, the value of body mass index (BMI) showed significant correlation with PI (p=0.04). The correlations of dietary total antioxidant indices with dietary intakes and anthropometric and biochemical biomarkers were assessed. Non-significant correlation was found between fasting blood sugar (FBS), hemoglobin A1C (HbA1C), vitamin B12, and vitamin D3 with ORAC index. Significant strong correlation showed for the value of iron in both ferric reducing ability of plasma (FRAP) and Oxygen Radical Absorbance Capacity (ORAC) indices (p<0.0001).

CONCLUSION

We find statistical significance correlation for dietary PI and BMI. The inflammatory and antioxidant properties of diet were not related to biochemical markers associated with obesity. Graphical abstract.

Twenty-five years of total antioxidant capacity measurement of foods and biological fluids: merits and limitations

This review summarises 25 years of investigations on antioxidants research in foods and biological fluids and critically analyses the merits and limitations of using the total antioxidant capacity (TAC) measurement in the metabolomic era. An enormous bulk of knowledge was produced regarding the antioxidant capacity of foods and large TAC databases were developed. A direct link between a food TAC value and any health benefit is erroneous and has led to several cases of consumer deception. However, the striking epidemiological evidence associating a high dietary TAC with some disease prevention and the availability of well-constructed TAC databases deserve attention and must be taken into account to establish the usefulness of measuring TAC in both foods and biological samples. The in vivo TAC measurement, usually performed in plasma, is influenced by many external factors, such as dietary habits, as well as environmental and behavioural factors, which are integrated towards homeostatic control by fine physiological mechanisms with high inter-individual variability. Therefore, plasma TAC cannot be considered as a unique biomarker of individual antioxidant status. However, the combined evaluation of plasma TAC with known markers of disease, individual metabolism, inflammation and genetics, as well as with markers of gut microbiota composition and activity, may lead to the identification of populations that are more responsive to food/diet TAC. In this framework, the appropriate use of TAC measurement both in food and in vivo can still provide support for the interpretation of complex phenomena and be a tool for sample screening when making a quick decision toward in-depth research investigations. © 2018 Society of Chemical Industry.

Dietary non-enzymatic antioxidant capacity and risk of stroke: The Swedish Women's Lifestyle and Health Cohort

OBJECTIVE

Consumption of antioxidant-rich foods has been associated with a reduced risk for stroke. However, antioxidant supplementation is not recommended owing to controversial findings reported in clinical trials. The aim of this study was to better understand the effect of dietary antioxidants by investigating the effect of dietary non-enzymatic antioxidant capacity (NEAC), reflecting the antioxidant potential of the whole diet, on the risk for stroke.

METHODS

In the Women's Lifestyle and Health Cohort, 45 882 women 30 to 49 y of age and free from cardiovascular diseases were followed through record linkages from 1991 to 2012. Dietary NEAC was assessed by a validated food frequency questionnaire collected at baseline and categorized into quintiles. Multivariable Cox proportional hazard regression models were fitted to estimate hazard ratios with 95% confidence intervals for overall stroke and ischemic and hemorrhagic stroke separately.

RESULTS

During a mean follow-up time of 20.2 y, we detected 871 incidence cases of stroke (516 ischemic, 296 hemorrhagic, and 59 unspecified strokes). After adjusting for potential confounders, we did not find any association between dietary NEAC and stroke, either overall, or ischemic or hemorrhagic stroke (Ptrend > 0.05).

CONCLUSION

Higher dietary NEAC was not associated with any type of stroke in young and middle-aged Swedish women.

Relative Validity of Dietary Total Antioxidant Capacity for Predicting All-Cause Mortality in Comparison to Diet Quality Indexes in US Adults

While traditionally diet quality index scores (DQIS) as noted later in this abstract have been used to predict health outcomes, dietary total antioxidant capacity (TAC), a useful tool for assessing total antioxidant power in the diet, may also be a novel predictor. This study evaluated the associations between dietary TAC and DQIS and all-cause mortality. Based on the National Health and Nutrition Examination Survey (NHANES) 1988-1994 and 1999-2006, 23,797 US adults were followed-up until 2015. Dietary TAC and DQIS including the Healthy Eating Index-2015 (HEI-2015), Alternative Healthy Eating Index-2010 (AHEI-2010), alternate Mediterranean Diet (aMED), and Dietary Approaches to Stop Hypertension (DASH) were calculated using a 1-day 24 h dietary recall. US adults in the highest quintiles of DQIS had lower rates of all-cause mortality compared to those in the lowest quintiles (HEI-2015 hazard ratio (HR): 0.87, 95% confidence interval (CI): 0.77-0.98; AHEI-2010 HR: 0.84, 95% CI: 0.74-0.94; aMED HR: 0.79, 95% CI: 0.69-0.90; DASH HR: 0.80, 95% CI: 0.70-0.92). Similarly, those in the highest quintile of dietary TAC also had a lower all-cause mortality than those in the lowest quintile (HR: 0.88, 95% CI: 0.79-0.98). These findings suggest that dietary TAC might be a relatively valid predictor of all-cause mortality in the US population compared to the DQIS.

Dietary total antioxidant capacity in relation to stroke among Iranian adults

Objective: This study was conducted to investigate the association between dietary TAC and odds of stroke among Iranian adults.Methods: This case-control study was done on 195 hospitalized stroke cases and 195 hospital-based controls in Al-Zahra hospital, Isfahan, Iran. Dietary TAC was estimated using the ferric-reducing antioxidant power (FRAP) international databases. Stroke was confirmed by a trained neurologist using standard imaging methods.Results: Mean dietary TAC was not significantly different comparing cases and controls (10.2 ± 6.0 vs. 10.4 ± 4.8, P = 0.61). However, after adjustment for potential confounders including dietary intakes of fiber and omega-3 fatty acids, we found an almost significant inverse association between dietary TAC and odds of stroke; such that each unit increase in dietary TAC was associated with 29% reduced odds of stroke (OR: 0.71; 95% CI: 0.50-1.01, P = 0.06). When we examined the association across tertiles of dietary TAC, we found that after controlling for potential confounders, those in the top tertile of dietary TAC were 51% less likely to have a stroke than those in the bottom tertile (0.49; 0.23-1.00).Discussion: We found an almost significant inverse association between dietary TAC and odds of stroke.

Dietary total antioxidant capacity is inversely associated with depression, anxiety and some oxidative stress biomarkers in postmenopausal women: a cross-sectional study

BACKGROUND

Postmenopausal women are at higher risk of mental disorders. Oxidative stress has implication in the development of these disorders. Dietary total antioxidant capacity (DTAC) has been proposed as a tool for assessing dietary antioxidants intake. The relationship between DTAC with depression, anxiety and stress has not been investigated in postmenopausal women. Thus, we aimed to assess the association between DTAC and depression, stress and anxiety as well as oxidative stress biomarkers.

METHODS

This cross-sectional study was carried out on 175 postmenopausal women. Data on dietary intake and mental health were collected by 147-item semi-quantitative food frequency questionnaires (FFQ) and Depression Anxiety Stress Scales (DASS-42), respectively. Dietary and serum total antioxidant capacity (TAC), malondialdehyde (MDA), oxidized-LDL, and superoxide dismutase (SOD) were measured. ANOVA test was applied to compare the mean of variables across the tertiles of DTAC. The relationship between DTAC and oxidative stress biomarkers was determined through ANCOVA method. Simple and multivariate linear regression tests were performed to measure the relationship between DTAC and mental health.

RESULTS

Serum MDA level was significantly lower in the subjects at the highest tertiles of DTAC (P-value < 0.001). In addition, serum TAC level was significantly higher in subjects at the second tertile of DTAC (P-value = 0.04). DTAC was inversely and independently related to depression (β = - 0.16, P-value = 0.03) and anxiety scores (β = - 0.21, P-value = 0.007). There was no significant association between DTAC and stress score (β = - 0.10, P-value = 0.1).

CONCLUSION

An inverse relationship was found between DTAC with depression, anxiety scores and some oxidative stress biomarkers in postmenopausal women. These findings indicate DTAC may be used for developing effective dietary measures for reducing depression and anxiety in these women.

Dietary total antioxidant capacity is inversely related to menopausal symptoms: a cross-sectional study among Iranian postmenopausal women

OBJECTIVE

The aim of this study was to assess the association between dietary total antioxidant capacity (DTAC) and menopausal symptoms (MS) in postmenopausal middle-aged women.

METHODS

A cross-sectional study was conducted with 400 postmenopausal women who referred to municipality health houses and health centers in south Tehran, Iran. Sociodemographic data and anthropometric measures such as body weight, height, and waist circumference were determined. Dietary intake was assessed using a 147-item validated food frequency questionnaire. Energy-adjusted DTAC was calculated using the US Department of Agriculture database. Individual MS was measured by the Menopause Rating Scale questionnaire.

RESULTS

Multivariable linear regression analyses indicated that DTAC was negatively associated with total Menopause Rating Scale score, somatic and psychological score, which was independent of confounding variables such as age, education, waist circumference, total physical activity, dietary intake of fiber, tea and coffee intake, total energy intake, and dietary supplement use (P < 0.001). Additionally, in logistic regression, a negative association between MS and DTAC was observed, which was independent of confounding variables (P_trend = 0.002). Logistic regression for each symptom indicated that higher DTAC was associated with reduction in hot flashes and sweating, sleep problems, anxiety, exhaustion, and difficulty concentrating. However, a significant positive association was observed between DTAC and sexual problems.

CONCLUSION

DTAC is inversely associated with MS, which could be of particular significance for somatic and psychological symptoms. These findings indicate that DTAC could be an important basis for developing an effective dietary measure for reducing MS.

Dietary Total Antioxidant Capacity and Cardiovascular Disease Risk Factors: A Systematic Review of Observational Studies

OBJECTIVE

Measurement of dietary total antioxidant capacity (DTAC) is considered a new holistic dietary approach and assesses total antioxidants present in the overall diet. Our aim was to perform a comprehensive review of the literature on the association between DTAC and cardiovascular disease (CVD) risk factors.

METHODS

PubMed, Web of Science, and Scopus were used to conduct a comprehensive search for articles published on this topic through September 2017. There was no limit on earliest year of publication. The search was based on the following keywords: dietary total antioxidant capacity, nonenzymatic antioxidant capacity, total radical-trapping antioxidant parameter, ferric reducing ability of plasma, oxygen radical absorbance capacity, Trolox equivalent antioxidant capacity, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), total cholesterol (TC), waist circumference (WC), insulin resistance, homeostatic model assessment of insulin resistance (HOMA-IR), insulin, obesity, glucose, C-reactive protein (CRP), blood pressure (BP), and body mass index. In total, 16 papers were identified for inclusion in the present systematic review.

RESULTS

Most well-designed studies that evaluated associations between DTAC and CVD risk factors showed inverse associations for fasting blood glucose, CRP, BP, and WC and positive associations for HDL-C. However, there was no association between DTAC and LDL-C or TC in any of the studies. Results regarding the association of DTAC with insulin, HOMA-IR, high-sensitivity CRP, and TG in the published literature were inconsistent.

CONCLUSIONS

Findings indicated a substantial association between high DTAC and most CVD-related risk factors.

Interactions of Gut Microbiota, Endotoxemia, Immune Function, and Diet in Exertional Heatstroke

Exertional heatstroke (EHS) is a medical emergency that cannot be predicted, requires immediate whole-body cooling to reduce elevated internal body temperature, and is influenced by numerous host and environmental factors. Widely accepted predisposing factors (PDF) include prolonged or intense exercise, lack of heat acclimatization, sleep deprivation, dehydration, diet, alcohol abuse, drug use, chronic inflammation, febrile illness, older age, and nonsteroidal anti-inflammatory drug use. The present review links these factors to the human intestinal microbiota (IM) and diet, which previously have not been appreciated as PDF. This review also describes plausible mechanisms by which these PDF lead to EHS: endotoxemia resulting from elevated plasma lipopolysaccharide (i.e., a structural component of the outer membrane of Gram-negative bacteria) and tissue injury from oxygen free radicals. We propose that recognizing the lifestyle and host factors which are influenced by intestine-microbial interactions, and modifying habitual dietary patterns to alter the IM ecosystem, will encourage efficient immune function, optimize the intestinal epithelial barrier, and reduce EHS morbidity and mortality.

Dietary Polyphenol Intake, but Not the Dietary Total Antioxidant Capacity, Is Inversely Related to Cardiovascular Disease in Postmenopausal Polish Women: Results of WOBASZ and WOBASZ II Studies

The aim of the study was to assess the relationship between the dietary polyphenol intake (DPI) and the dietary total antioxidant capacity (DTAC) and the prevalence of cardiovascular disease (CVD) in postmenopausal women. Participants were 916 postmenopausal women diagnosed with CVD and 1683 postmenopausal women without history of CVD, who took part in the population-based studies carried out in Poland: WOBASZ (2003–2005) and WOBASZ II (2013-2014). Nutritional data were collected using a single 24-hour dietary recall. DPI and DTAC in the CVD women were significantly lower and accounted for 1766.39 mg/d and 10.84 mmol/d, respectively, versus 1920.57 mg/d and 11.85 mmol/d in the women without CVD, but these differences disappeared after the standardization for energy input. Also, in the multiple-adjustment model, higher DPI, but not DTAC, was associated with the reduced odds ratio for the prevalence of CVD. Beverages, mainly coffee and tea, contributed in more than 40% to DPI and in more than a half to DTAC. In this study, higher dietary polyphenol intake, but not the dietary total antioxidant capacity, was inversely associated with CVD in postmenopausal women, which points to the health benefits of increased polyphenol intake from food sources for these women.

Relation of antioxidant capacity of diet and markers of oxidative status with C-reactive protein and adipocytokines: a prospective study

BACKGROUND

The role of dietary antioxidants and plasma oxidant-antioxidant status in low-grade chronic inflammation and adipocytokine levels is not established yet.

OBJECTIVES

We aimed to evaluate whether total dietary antioxidant capacity (assessed by dietary ferric reducing antioxidant potential (FRAP)), serum uric acid (UA) and gamma glutamyltransferase (GGT) were associated with low-grade chronic inflammation and circulating adipocytokines.

METHODS

Data of 4506 participants aged ≥55years from the Rotterdam Study were analyzed. Baseline (1990-1993) FRAP score was assessed by a food frequency questionnaire. Baseline UA and GGT levels were assessed in non-fasting serum samples. Serum high sensitivity C-reactive protein (hs-CRP) was measured at baseline and 10years later. Plasma leptin, adiponectin, plasminogen activator inhibitor-1 (PAI-1) and resistin levels were assessed 10years later.

RESULTS

A high FRAP score was associated with lower levels of UA and GGT. Overall, no association was found between FRAP and hs-CRP levels. FRAP score was associated with lower levels of leptin and PAI-1, higher levels of adiponectin, and no difference in resistin levels. Increased levels of UA were associated with higher levels of hs-CRP, PAI-1 and leptin; lower levels of adiponectin and no difference in resistin levels. Similarly, GGT was associated with higher levels of hs-CRP whereas no association was observed between GGT and adipocytokines.

CONCLUSION

These findings suggest that overall antioxidant capacity of diet and low levels of UA are associated with circulating adipocytokines whereas no consistent association was found with hs-CRP.

Estimation of dietary total antioxidant capacity of Korean adults

PURPOSE

Dietary total antioxidant capacity (TAC) has been reported to be inversely associated with the risk of chronic diseases. However, little is known about dietary TAC among the Korean population. Therefore, we aimed to estimate the dietary TAC of Korean adults and to document the major food sources.

METHODS

We studied 33,581 Korean adults aged ≥19 years who participated in the Korea National Health and Nutrition Examination Survey 2007-2012. Dietary TAC was estimated from 1-day 24-h dietary recall data using a TAC database comprising antioxidant capacities of 42 dietary antioxidants, developed for common Korean foods.

RESULTS

The average dietary TAC of Korean adults was 384.7 mg VCE/d, and the major contributors were flavonoids, followed by vitamin C and E. The energy-adjusted daily TAC level was higher in women, middle-aged adults, non-regular alcohol consumers, current non-smokers, supplement users, and in those with a higher income and education level than in their counterparts (P < 0.001). Fruits (47.3%), vegetables (28.4%), beverages and alcohols (11.2%), and legumes and legume products (5.5%), in particular, grapes, persimmons, mandarins, apples, and green tea, were major food sources of dietary TAC. In addition, the consumption of nutrient-dense foods, such as fruits and vegetables, increased, whereas the intake of energy and fat decreased across quartiles of energy-adjusted dietary TAC.

CONCLUSIONS

The present study documented the baseline dietary TAC of Korean adults and the major food sources thereof using nationally representative data. Further research on the health effects of dietary TAC among Korean adults is warranted.

Inverse association linking serum levels of potential antioxidant vitamins with C-reactive protein levels using a novel analytical approach

Exposures to antioxidants (AO) are associated with levels of C-reactive protein (CRP), but the pattern of evidence is mixed, due in part to studying each potential AO, one at a time, when multiple AO exposures might affect CRP levels. By studying multiple AO via a composite indicator approach, we estimate the degree to which serum CRP level is associated with serum AO level. Standardised field survey protocols for the US National Health and Nutrition Examination Survey (NHANES) 2003-2006 yielded nationally representative cross-sectional samples of adults aged 20 years and older (n 8841). NHANES latex-enhanced nephelometry quantified serum CRP levels. Liquid chromatography quantified serum concentrations of vitamins A, E and C and carotenoids. Using structural equations, we regressed CRP level on AO levels, and derived a summary estimate for a composite of these potential antioxidants (CPA), with covariates held constant. The association linking CPA with CRP was inverse, stronger for slightly elevated CRP (1·8≤CRP<10 mg/l; slope= -1·08; 95 % CI -1·39, -0·77) and weaker for highly elevated CRP (≥10 mg/l; slope= -0·52; 95 % CI -0·68, -0·35), with little change when covariates were added. Vitamins A and C, as well as lutein+zeaxanthin, were prominent contributors to the composite. In these cross-sectional data studied via a composite indicator approach, the CPA level and the CRP level were inversely related. The stage is set for more confirmatory longitudinal or intervention research on multiple vitamins. The composite indicator approach might be most useful in epidemiology when several exposure constructs are too weakly inter-correlated to be studied via formal measurement models for underlying latent dimensions.

Association between circulating CCL2 levels and modifiable behaviors in overweight and obese adolescents: a cross-sectional pilot study

BACKGROUND

We evaluated the relationship between an early inflammatory biomarker, chemokine (C-C motif) ligand 2 (CCL2), and other clinical biomarkers and lifestyle behaviors, in overweight/obese adolescents at high risk of developing cardiometabolic derangements.

METHODS

We collected anthropometric measurements, clinical biomarkers, and three 24-h dietary recalls from 21 vocational high school students (91% male), 14-19 years, with body mass index (BMI) ≥25 kg/m2. Pearson's or Spearman's correlation coefficients were used to examine relationships.

RESULTS

Mean BMI was 33.2 kg/m2 (range 25.7-45.6) and 38% were prediabetic by fasting glucose. Mean CCL2 was 512.9 pg/mL (range 220-917) and positively correlated with triglycerides (r=0.45; p=0.04) and TNF-α (r=0.57; p=0.007) and marginally negatively correlated with fruit/vegetable intake (r=-0.42, p=0.06) and omega-3 fatty acids (r=-0.41, p=0.07).

CONCLUSIONS

CCL2 was positively associated with pro-inflammatory biomarkers and negatively associated with some anti-inflammatory dietary factors.

Greater Total Antioxidant Capacity from Diet and Supplements Is Associated with a Less Atherogenic Blood Profile in U.S. Adults

Evidence from epidemiologic studies has shown that total antioxidant capacity (TAC) in the diet might be inversely associated with stroke, heart failure, and inflammatory biomarkers. However, studies on the association of TAC from both diet and supplements with cardiovascular disease (CVD) risk factors in the U.S. population are lacking. This cross-sectional population-based study aimed to investigate the association of TAC with both diet and supplements with CVD risk factors among 4039 U.S. adults in National Health and Nutrition Examination Survey (NHANES) 2007–2012. TAC from both food sources and dietary supplements was estimated from two 24-h dietary recalls using the NHANES supplement ingredient database, United States Department of Agriculture (USDA) proanthocyanidin, flavonoid, and isoflavone databases. Top contributors to TAC were tea, antioxidant supplements, vegetable mixture, orange juice, berries, and wine. Antioxidant supplement users had 1.6 times higher TAC than non-users. Greater TAC was associated with reduced triglycerides (TG) (−1.39% change; 95% CI = −2.56 to −0.21), TG to high-density lipoprotein cholesterol (HDL-C) ratio (−2.03% change; 95% CI = −3.45 to −0.60), HDL-C (0.65% change; 95% CI = 0.07 to 1.23), insulin (−1.37% change; 95% CI = −2.64 to −0.09), homeostasis model assessment of insulin resistance (HOMA-IR) (−1.57% change; 95% CI = −3.02 to −0.09) and C-reactive protein (CRP) (−0.83% change; 95% CI = −1.29 to −0.38) after adjusting for potential confounders. There was no significant association between TAC and waist circumference, BMI, blood pressure, low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), and fasting glucose. The findings of this study support the hypothesis that an antioxidant-rich diet and intake of supplements are beneficial to reduce CVD risk.

Improvement and Interlaboratory Validation of the Lipophilic Oxygen Radical Absorbance Capacity: Determination of Antioxidant Capacities of Lipophilic Antioxidant Solutions and Food Extracts

A lipophilic oxygen radical absorbance capacity (L-ORAC) assay is an evaluation of the antioxidant capacity of solutions of lipophilic compounds. The concentrations of fluorescein, radical generator, and Trolox standard solutions were optimized to improve the precision of the assay. An interlaboratory study using two antioxidant solutions and three food extracts as test samples conducted in accordance with harmonized protocol demonstrated satisfactory L-ORAC measurements; the intermediate precision relative standard deviations (RSD(int)) ranged from 7.0 to 16.7%, the reproducibility relative standard deviations (RSD(R)) ranged from 14.8 to 19.4%, and the HorRat values ranged from 1.35 to 1.78.