Dietary Total Antioxidant Capacity Is Associated with Diet and Plasma Antioxidant Status in Healthy Young Adults

The contribution of dietary total antioxidant capacity to type 2 diabetes risk and levels of glycemic biomarkers: a systematic review

BACKGROUND

This study systematically reviewed and analyzed epidemiological evidence regarding the association between dietary total antioxidant capacity (DTAC) and both the risk of developing diabetes and glycemic biomarker levels.

METHODS

We searched the PubMed, Scopus, ScienceDirect, and Google Scholar databases through July 2024 without imposing any date restrictions. Original studies that examined the relationship between DTAC and either the risk of developing diabetes or glycemic biomarker levels-specifically fasting blood glucose (FBG), hemoglobin A1C (HbA1C), insulin, and the homeostatic model assessment for insulin resistance (HOMA-IR)-were eligible for inclusion. After eliminating duplicates and irrelevant records, relevant studies were selected, and data were extracted through rigorous critical analysis.

RESULTS

A total of 32 articles were included in the review. Of the 19 studies that evaluated diabetes risk, 15 reported a lower risk among subjects with higher DTAC values. All 4 studies examining prediabetes risk found lower risk in participants with high DTAC scores. Additionally, significant inverse relationships were observed between DTAC values and FBG (9/15 studies), HbA1C (1/6 studies), insulin (5/6 studies), and HOMA-IR (8/9 studies).

CONCLUSION

The majority of evidence indicates that high adherence to an antioxidant-rich diet may reduce diabetes risk and improve glycemic biomarkers, including FBG, insulin, and HOMA-IR.

Factors associated with the dietary total antioxidant capacity of pregnant Brazilian women

OBJECTIVE

To investigate the sociodemographic, maternal, and gestational factors associated with the dietary total antioxidant capacity in pregnant Brazilian women.

METHODS

A cross-sectional study with 2,232 pregnant women aged 18 years old or older, in the first, second, and third trimesters of pregnancy, from eleven cities in the five Brazilian regions. A semi-structured questionnaire was applied to assess socioeconomic, demographic, and health data, and a 24-hour dietary recall (R24h) was used to assess food consumption and analyze the dietary total antioxidant capacity (DTAC), estimated using the ferric reducing antioxidant power (FRAP) method.

RESULTS

The median of DTAC was 5.32 mmol/day. Aracaju, Sergipe (SE) had the highest median of DTAC (6.44 mmol/day) and Palmas, Tocantins (TO) had the lowest (4.71 mmol/day). Pregnant women aged 20 to 34 years (OR 1.86; 95%CI 1.26-2.76), 35 years old or older (OR 3.68; 95%CI 2.21-6.14) and who were in the second trimester of pregnancy (OR 1.50; 95%CI 1.11-2.01) were more likely to be above the median DTAC. While pregnant women with higher education had a 67% lower chance of being above the median DTAC (OR 0.67; 95%CI 0.48-0.92).

CONCLUSION

The study demonstrated that there are differences in antioxidant consumption in different cities in Brazil and that associated factors such as age, education, and gestational trimester can impact the intake of foods rich in antioxidants. The profile found draws attention to the importance of an adequate diet rich in antioxidants during prenatal care.

The Essential Role of Traditional Chinese Medicine Compounds in Regulating Recurrent Spontaneous Abortion by Inhibiting Oxidative Stress

Due to the lack of accurate registration of RSA and miscarriages, many early miscarriages are overlooked and not diagnosed or treated promptly in hospitals. This uncertainty in pathogenesis prevents clinicians from taking targeted therapeutic measures, leading to unsatisfactory treatment outcomes and placing a heavy burden on the patient's family and the healthcare system. Oxidative stress is present in embryonic development and affects the regulation of oxidative stress in pregnancy and the reproductive endocrine system. Oxidative stress injury is a significant pathogenesis of RSA, so improving the body's ability to resist oxidative stress injury is crucial in treating RSA. For patients with RSA, there is an urgent need for safe, efficient, and cost-effective anti-oxidative stress drugs, and there is growing evidence that treatment with Traditional Chinese medicine (TCM) can improve pregnancy success with fewer adverse effects. Many active ingredients for treating RSA are mainly derived from certain components of TCM, including flavonoids, phenols, and other compounds, which have been shown to treat RSA directly or indirectly by targeting anti-oxidative stress-related pathways. This article summarizes the experimental and clinical evidence of several common TCM compounds for treating RSA. It provides ideas and perspectives for further exploring the pathogenesis of RSA and TCM compounds for treating RSA.

Autoantibodies, Oxidative Stress, and Nutritional State in Anorexia Nervosa

Background/Objectives: Anorexia nervosa (AN) is a complex psychiatric disorder characterized by an extreme fear of gaining weight, leading to severe calorie restriction and weight loss. Beyond its psychiatric challenges, AN has significant physical consequences affecting multiple organ systems. Recent research has increasingly focused on the interplay between autoantibodies, oxidative stress, and nutritional state in this condition. Methods: Ninety-six subjects were evaluated: forty-eight with AN and forty-eight normal-weight control subjects. The serum levels of IgG reactive to hypothalamic antigens, uric acid, and total antioxidant capacity were evaluated by laboratory assays. Results: Anti-hypothalamic autoantibodies were found in AN patients. Furthermore, increased levels of oxidative stress were reported, as measured by decreased serum uric acid and total antioxidant capacity (TAC), and they reduced with the disease duration and the restoration of body mass index (BMI). Finally, a decrease in both autoantibodies and oxidative stress was observed as patients' clinical condition improved, as measured by time since diagnosis and BMI recovery. Conclusions: The clinical improvement of AN patients seems to be associated with a decrease in the autoimmune response to hypothalamic cellular antigens and a reduction in oxidative stress. Dysregulation of the immune system and oxidative stress appear to be interconnected in various diseases, including autoimmune and psychiatric disorders. These findings, although preliminary, may offer potential avenues for the treatment of this challenging condition.

Dietary antioxidant capacity is inversely associated with F2- isoprostane and body fat percentage in elite soccer referees

Background Dietary antioxidant Capacity (DaC) has been used as a tool for predicting plasma and dietary antioxidant concentrations. However, the DaC association with oxidative stress (OS) and body composition parameters is an unexplored area, mainly in physically active individuals. Given the potential for increased OS in physically active individuals, it becomes crucial to investigate this association. The aim of this study was to analyze the association between DaC, OS biomarkers, and body composition in healthy and physically active individuals. Methods This Cross-sectional study included 20 male soccer referees. Body composition measurements (body mass, fat mass, lean mass, and waist circumference), OS biomarkers (F2-isoprostane, total antioxidant state, total oxidative status, reduced glutathione, oxidized glutathione, superoxide dismutase, glutathione peroxidase (GPx) and catalase), and DaC were evaluated. Linear regression models were used to determine the association between DaC and the dependent variables. The study was approved by the Human Research Ethics Committee of the Federal University of Santa Catarina (UFSC), CAAE 82584318.0.0000.0121, and file no. 2.572.301. Results DaC was inversely associated with F2-isoprostane (p = 0.044), GPx activity (p = 0.048), and body fat percentage (p = 0.025). Conclusions Increased DaC in physically active individuals may bring benefits related to biomarkers of OS, such as decreasing F2-isoprostane and increasing GPx activity. The increase in DaC also showed an improvement in body composition, demonstrated by the lower percentage of body fat in the study subjects.

Supplementation of curcumin promotes the intestinal structure, immune barrier function and cecal microbiota composition of laying hens in early laying period

The prelaying period is critical for laying hens, marked by significant physiological changes such as increased egg production, hormone secretion, and higher nutritional demands. These changes stress the intestine, which is vital for nutrient digestion, absorption, immune defense, and maintaining antioxidant and microbial balance. During this period, maintaining the intestinal health is essential for efficient nutrient absorption. Curcumin, a plant-derived extract, offers antioxidant, anti-inflammatory, antimicrobial, and immunomodulatory benefits, that can improve gut function. This study evaluated the effects of curcumin on the intestinal structure, immune barrier function, and cecal microbiota composition in laying hens during their early laying period. A total of 180 Snowy White chickens (154 days old) were divided into 5 experimental groups, receiving curcumin at 0 mg/kg, 100 mg/kg, 200 mg/kg, 300 mg/kg, and 400 mg/kg for 12 wk. The results showed that curcumin significantly improved the intestinal morphology (P < 0.05), increased mRNA expression of digestive enzymes (such as MGAM, SI, and ANPEP), and enhanced the digestive and absorptive functions. Further, curcumin improved the levels of antioxidant parameters (such as CAT, GSH-PX, T-AOC, and T-SOD) in the ileum, jejunum, and duodenum, and increased the expression of immunoglobulins (IgA, IgM, IgG) in the intestinal segments and serum (P < 0.05). Curcumin also improved the intestinal immune barrier function by increasing ZO-1 and Occludin expression. Furthermore, it altered the gut microbiota composition by increasing the relative abundance of beneficial bacterial phyla such as Bacteroidetes, Actinobacteria, Proteobacteria, and Fusobacteria (P < 0.05). At the genus level, curcumin supplementation enhanced the beneficial genera like Phocaeicola, Alistipes, Prevotella, Barnesiella, and Bifidobacterium (P < 0.05), thereby promoting the gut health and microbial diversity. In conclusion, curcumin supplementation during the early laying period of hens offers significant benefits by improving the intestinal health, immune function, and gut microbiota composition. Hence, curcumin serves as a promising dietary additive to support nutrient absorption and immune defense in laying hens during the early laying period of hens.

Association of healthy eating index (HEI), alternative healthy eating index (AHEI) with antioxidant capacity of maternal breast milk and infant's urine: a cross-sectional study

Maternal dietary quality may alter the nutrient content of breast milk. In this study, we aimed to investigate the relationship between the healthy eating index (HEI) and alternative healthy eating index (AHEI) of a breastfeeding mother's diet with the antioxidant profile of her breast milk and her infant's urine. This study included 300 healthy mother-infant pairs. The participants' dietary intake was estimated using a validated semi-quantitative food frequency questionnaire. The diet quality of participants was assessed using the HEI and AHEI. The total antioxidant content of the breast milk and infant's urine was evaluated using ferric reducing antioxidant power (FRAP), 2, 2'-diphenyl-1-picrylhydrazyl (DPPH), thiobarbituric acid reactive substances (TBARs), and Thiol quantification assays. After adjusting for confounding factors, the odds of a low malondialdehyde (MDA) content of breast milk were significantly higher in the highest quartile of HEI than in the lowest quartile. The odds of low DPPH and FRAP in infant urine decreased in the highest quartile of HEI compared to the lowest quartile. No significant relationship was found between AHEI and antioxidant levels of breast milk and the infant's urine. Our findings demonstrate that a high quality diet of breastfeeding mothers, identified by a higher HEI, can affect the oxidant-antioxidant balance of a mother's breast milk and her infant's urine.

Association of dietary antioxidant indices with kidney function indicators in patients with type 2 diabetes: a cross-sectional study

This cross-sectional study investigated the relationship between dietary antioxidant indices and kidney function indicators in 240 outpatient adults with type 2 diabetes. Dietary intake was assessed using three 24-h dietary recalls. Dietary total antioxidant capacity (DTAC), dietary antioxidant index (DAI), and dietary antioxidant quality score (DAQS) were obtained. Indicators of kidney function, including serum creatinine, urea, blood urea nitrogen (BUN), and glomerular filtration rate (GFR), were extracted from medical records. After adjustment, the highest DAI tertile had lower serum creatinine (0.98 ± 0.27 vs 1.03 ± 0.32 mg/dL, P < 0.001), reduced urea (30.97 ± 8.75 vs 34.07 ± 14.45 mg/dL, P = 0.005), and higher GFR (85.16 ± 29.43 vs 74.16 ± 22.18 ml/min per 1·73 m2, P < 0.001) compared to the lowest tertile. The results of logistic regression analysis indicated a borderline significant inverse association of serum urea > 20 mg/dl with DTAC (odds ratio (OR):0.28; 95% CI: 0.07-1.09; Ptrend = 0.06). Multivariable linear regression analysis revealed a significant aligned correlation between DAQs and GFR (β: 0.20; P-value: 0.005) and a marginally significant direct relationship between DAI and GFR (β: 0.14; P-value: 0.06). However, no significant association was observed for DTAC with GFR (β:-0.02; P-value: 0.80). Diets with higher antioxidant capacity may be linked to improved kidney function in type 2 diabetes but our results did not support this strongly.

Dietary total antioxidant capacity in relation to disease severity and risk of mortality in cirrhosis; results from a cohort study

Liver Cirrhosis, defined as the final stage of chronic liver disease, may become more prevalent in the lower level of body defense against oxidation and inflammation. Therefore, we assessed the association of dietary total antioxidant capacity (DTAC) with the severity and mortality of cirrhosis in a cohort study. 120 newly diagnosed cirrhosis patients from Tehran, Iran, participated in this study. The patients' habitual diet was assessed using a 168-item validated food frequency questionnaire. Both ferric-reducing antioxidant potential (FRAP) and oxygen radical scavenging capacity (ORAC) methods were computed to achieve DTAC scores. The association between DTAC with disease severity and mortality was estimated by multivariate linear regression and cox proportional hazards regression models. Dietary total antioxidant capacity-ORAC had a significant inverse association with disease severity in both crude and adjusted models (P for trend: <0.001 and 0.016 respectively). The risk of mortality in the first and second tertiles of ORAC was 5.56 (95 % CI: 2.25-13.75; P = 0.002) and 3.20 (95 % CI: 1.25-8.19; P = 0.015) higher than those in the third category, respectively. In conclusion, a higher antioxidant capacity of diet is associated with less disease severity and mortality risk in cirrhosis.

The association of dietary total antioxidant capacity and gestational diabetes: a prospective cohort study from the Mothers and their children's health (MATCH)

BACKGROUND/OBJECTIVES

There is evidence to support the hypothesis that a diet rich in antioxidants can help safeguard against the development of gestational diabetes mellitus (GDM). This study aimed to investigate the association between dietary total antioxidant capacity (DTAC) during early pregnancy and the risk of GDM.

SUBJECTS/METHODS

We included 1856 pregnant women in their first trimester from the Mothers and their Children's Health (MATCH) prospective cohort study. Prepregnancy dietary intake was assessed using a validated food frequency questionnaire (FFQ) and was used to calculate the DTAC score. Incident GDM was diagnosed based on the American Diabetes Association criteria. We estimated the association between DTAC and GDM using propensity score-based inverse probability weighting (IPW).

RESULTS

Overall, 369 (14.6%) of the pregnant women were identified with GDM. The mean DTAC score and the corresponding standard deviation (SD) was 2.82± (2.56) mmol/100 g, with a range of 0.01 to 18.55. The adjusted risk of GDM decreased by 34% (95% CI = 10%, 52%, p = 0.023) for each DTAC score increase. The results showed that women in the highest quartile of DTAC had a lower risk of developing GDM compared to those in the lowest quartile (adjusted RR: 0.29, 95% CI: 0.12, 0.68, p = 0.005).

CONCLUSION

DTAC in early pregnancy is significantly associated with a lower risk of GDM. Additional larger cohort studies are needed to validate these findings.

The association between dietary inflammatory index and dietary total antioxidant capacity and Hashimoto's thyroiditis: a case-control study

BACKGROUND

Hashimoto's thyroiditis (HT) is an inflammatory disease characterized by increased reactive oxygen species. Diets rich in anti-inflammatory and antioxidant properties may be linked to a reduced risk of developing HT. The aim of this study was to investigate the association between the dietary inflammatory index (DII) and dietary total antioxidant capacity (DTAC) with HT in Iranian adults.

METHODS

The study was a hospital-based case-control study conducted on 230 participants (115 cases and 115 controls). Dietary intake was assessed using a food frequency questionnaire (FFQ). The FFQ data were used to calculate DII and DTAC scores. Anthropometric measurements, thyroid function, and antibody tests were evaluated using standard methods. Multivariable logistic regression analysis was performed in both raw and adjusted models to determine the association between DII and DTAC scores with HT.

RESULTS

The average age of the participants was 39.76 ± 9.52 years. The mean body mass index in the case and control groups was 28.03 ± 6.32 and 26.43 ± 5.13 (kg/m2), respectively (P = 0.036). In the HT group, the DII level was higher (P < 0.001) and the DTAC level was lower than those in the healthy group (P = 0.047). In the multivariable logistic regression model, after adjusting for confounding factors, subjects in the last tertile of DII had a nonsignificantly higher HT risk than those in the first tertile (OR = 1.75; 95% CI = 0.83-3.65; P = 0.130). Regarding DTAC, the subjects in the last tertile of DTAC had a significantly decreased risk of HT (OR = 0.47; 95% CI = 0.23-0.98; P = 0.043) compared to those in the first tertile. The DII had a positive correlation with anti-thyroid peroxidase antibody (anti-TPO), thyroglobulin antibodies (TG-Ab) and thyroid-stimulating hormone, while DTAC had a negative correlation with anti-TPO and TG-Ab (P < 0.050).

CONCLUSION

The increase in DII is not associated with an increase in the risk of HT, while DTAC can significantly reduce its risk. Having an anti-inflammatory and antioxidative diet can be effective in improving thyroid function. These conclusions should be confirmed in additional prospective studies.

The association of dietary total antioxidant capacity with migraine attack frequency in women

AIMS

There is substantial evidence considering oxidative stress as one of the migraine pathogeneses. It seems higher dietary antioxidant intake could modulate migraine symptoms in sufferers. Therefore, we assessed the relationship between the dietary total antioxidant capacity (TAC) and migraine attack frequency.

METHOD

289 volunteer women with migraine were recruited. The usual participants' dietary intakes were collected using a validated food frequency questionnaire. The dietary total antioxidant capacity of women was determined via three different indices including dTAC, DAI, and DAQs. dTAC was calculated based on the USDA oxygen radical absorbance capacity (ORAC) database. The dietary intakes of vitamins A, E, C, selenium, zinc, and manganese were applied for calculating the DAI (Dietary Antioxidant Index) and DAQs (Dietary Antioxidant Quality score). The multivariate-adjusted ordinal regression was used to assess the relation of three indices scores with migraine attack frequency.

RESULTS

a lower score of dTAC was associated with a higher attack frequency [OR (95%CI) model3= 1.97(1.1-3.54), P-value= 0.02]. The women with DAQs= 1 and 3 had significantly higher migraine attack frequency compared to women with DAQs = 5 [DAQs = 1: OR (95%CI) model 3= 8.59 (1.06- 69.72), P-value = 0.04] and [DAQs = 3: OR (95%CI) model 3= 2.09 (1.13- 3.85), P-value= 0.02]. Moreover, the trend of changes among the DAQs and dTAC levels was significant (P-values for trend < 0.05). There was no significant association between tertiles of DAI and migraine attack frequency (P-value> 0.05).

CONCLUSION

A high-quality diet in terms of antioxidant capacity is related to lower attack frequency in migrainous women.

Association of dietary total antioxidant capacity with general and abdominal obesity in type 2 diabetes mellitus patients

BACKGROUND

The dual existence of Type 2 Diabetes Mellitus (T2DM) and obesity within a single individual may describe a combined adverse health effects, including impaired quality of life and increased risk for cardiovascular diseases (CVDs). Oxidative stress is a contributing factor to the pathogenesis of obesity. Meanwhile, dietary antioxidants may improve the antioxidant defense system and thereby decrease oxidative injury. Dietary total antioxidant capacity (TAC) is usually used to investigate the potential health effects of dietary antioxidant intake on several oxidative stress induced chronic diseases. This study aimed to examine the association of dietary TAC with obesity-related features in T2DM patients.

METHODS

The present study included 254 type 2 diabetes outpatients with a mean (SD) age of 54.52 (7.21) years and mean (SD) diabetes duration of 8.2 (6.4) years. Data on dietary intake was assessed using a validated food frequency questionnaire. Dietary TAC was estimated by ferric reducing antioxidant potential (FRAP) method. Anthropometric, clinical and lifestyle characteristics were all collected.

RESULTS

In linear regression analyses, dietary antioxidant capacity was inversely associated with body mass index (β = -0,231; 95% CI, -0,419 to -0,042), waist circumference (β = -0,427; 95% CI, -0,849 to -0,006) and fat mass percentage (β = -0,328; 95% CI, -0,545 to -0,112) independently of the assessed confounding variables. Interestingly, dietary TAC showed positive and significant associations with vitamin A, vitamin C, β-carotene, magnesium, folic acid and iron intakes, after adjusting for age and daily energy intake.

CONCLUSIONS

Higher intake of dietary TAC was in association with lower indices of general and central obesity in T2DM patients. Therefore, dietary recommendations for counteracting obesity in patients with T2DM should take into account a high dietary TAC.

Postprandial Antioxidative Response to Ingestion of Formulated Date- and Fruit-Based Nutritional Bars by Healthy Individuals

Nutritional bars (NBs) are gaining popularity among healthy and athletic individuals, but postprandial antioxidative response has not been investigated. Therefore, the current study examined the postprandial alterations in total phenolic content (TPC), total antioxidant capacity (T-AOC), malondialdehyde (MDA), and Superoxide dismutase (SOD) in the plasma of healthy individuals after the ingestion of 140 g (510 Kcal) from formulated date-based bars (DBBs) or fruit-based bars (FBBs). Firstly, the free and bound phenolic contents (PCs) were determined to be 10.15 and 12.98 and 6.19 and 3.57 mg GAE g-1, respectively. FBBs were significantly higher in free PC than DBBs, while DBBs were considerably higher in bound PC than FBBs. Secondly, twenty participants with age, height, weight, body mass index (BMI), fat mass, and fat-free mass averages of 21.4 years, 170.0 cm, 66.3 kg, 22.9 kg m2, 14.5, and 29.2 kg, respectively, were subjected to metabolic experiments (ISRCTN19386758). Ingestion of 140 g of FBB or DBB resulted in 288.50 or 302.14 µg TPC mL-1 blood, respectively. Postprandial TPC content increased with time progression and peaked after 120 min. T-AOC contents averaged 22.63 and 23.61 U mL-1 before ingestion of FBBs or DBBs, respectively. The T-AOC content increased significantly 120 and 180 min after ingestion of DBBs, while no significant change was noted after consuming FBBs. A significant decrease in MDA content was observed 180 min after consuming DBBs, while no significant change was noted after consuming FBBs. SOD concentrations ranged from 193.99 to 201.07 U L-1 in FBBs and DBBs, respectively. No considerable response was noted up to 3 h after ingestion of FBBs. On the contrary, a significant response was found 120 min after consuming DBBs. Pearson's correlation coefficient indicated a highly significant positive correlation coefficient (p < 0.01) between T-AOC and either MDA or SOD, as well as between MDA and SOD. The principal component analysis demonstrated a strong and positive relationship between SOD and TPC at 60 and 120 min after DBB ingestion. In conclusion, the relative changes in postprandial responses in T-AOC and MDA did not significantly (p > 0.05) differ between DBBs and FBBs, except for TPC (p = 0.04, paired t-test) and SOD (p = 0.003, paired t-test). Further studies with an extended experimental time are needed to confirm the current findings.

Dietary antioxidants and hypertension among menopausal women in Rafsanjan Cohort Study

Studies on the beneficial role of dietary antioxidants in preventing or managing hypertension in postmenopausal women are infrequent. The present cross-sectional study aimed to assess the association between dietary antioxidants and hypertension among menopausal women in Rafsanjan, a city located in the southeast of Iran. This study was based on data from the Rafsanjan Cohort Study (RCS), as part of the Prospective Epidemiological Research Studies in IrAN (PERSIAN). Among 2359 postmenopausal women, finally, 1936 women were included in this study. Participants were grouped as having normal blood pressure (BP), elevated BP, stage 1 hypertension, or stage 2 hypertension as defined by the 2017 American College of Cardiology (ACC)/American Heart Association (AHA) BP guideline. A food frequency questionnaire (FFQ), was utilized to ascertain the levels of various nutrients and dietary antioxidants in the diet. The association between dietary intakes of antioxidants and blood pressure groups was evaluated by crude and adjusted models in the multinominal logistics regression analysis. Normal BP, elevated BP, stage 1 hypertension, and stage 2 hypertension were observed in 35.69%, 3.62%, 10.59%, and 50.10% of postmenopausal women respectively. In the adjusted model, in subjects with higher consumption of β-carotene, the odds ratios of elevated BP in the 3rd quartile was about 2 times (OR: 2.04 (1.06-3.93) higher than 1st quartile. Also, in subjects with medium quality of DAQS, the odds ratios of elevated BP and stage 1 blood pressure were about 2 times (OR: 2.09 (1.05-4.17) and 1.69 times (OR: 1.69 (1.09-2.63) higher than subjects with low quality respectively. Furthermore, we did not find any statistically significant association between increased intake of dietary antioxidants and decreased odds of hypertension. After controlling the effects of confounding variables, increased dietary intake of selenium, carotenoids, vitamin A, vitamin C, and vitamin E did not decrease the odds of hypertension in postmenopausal women. Accordingly, it is suggested that this association be further investigated in the follow-up phase of this prospective study.

The impact of bacillus pumilus TS2 isolated from yaks on growth performance, gut microbial community, antioxidant activity, and cytokines related to immunity and inflammation in broilers

Intensive poultry farming faces challenges like gut inflammation in the absence of antibiotics, resulting in reduced productivity, heightened susceptibility to enteric diseases, and other complications. Alternative strategies are needed to manage inflammation and maintain sustainable poultry production. Yaks living in high-altitude hypoxic environments have specialized gut microbes. However, yak probiotics remain largely uncharacterized. We previously isolated a strain of Bacillus pumilus (named TS2) from yaks and demonstrated its potential as a probiotic in vitro. Therefore, in this study, we evaluated the in vivo growth-promoting, antioxidant, immune, and anti-inflammatory effects of Bacillus pumilus isolated from yaks in broilers. We demonstrated the safety of TS2 isolated from yaks in broilers. Furthermore, we found that TS2 increased the average daily weight gain (ADWG) and reduced the feed conversion ratio (FCR). Supplementation with TS2 also improved the mucosal morphology, the ratio of villi to crypt cells, and enzyme activity. High-throughput sequencing showed that the abundance of Lactobacillus was higher in the TS2 treated broilers. Importantly, the serum level of malondialdehyde (MDA) was reduced and the levels of total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) activity were increased in the low-dose TS2 group, while the inflammatory factors interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were downregulated compared with the control group. We demonstrated that TS2 supplementation can increase the overall growth performance and ameliorate the blood parameters related to inflammation and immunity in broilers.

Association between dietary antioxidant capacity and type 2 diabetes mellitus in Chinese adults: a population-based cross-sectional study

BACKGROUND

Higher intakes of dietary antioxidants have been linked to a lower type 2 diabetes mellitus (T2DM) risk. However, few studies have comprehensively examined the overall dietary antioxidant capacity, assessed by dietary antioxidant quality scores (DAQS) and dietary total antioxidant capacity (DTAC), related to T2DM risk, especially in populations consuming relatively monotonous diets. This study aimed to evaluate the associations of DAQS, DTAC, and T2DM among rural Chinese adults.

METHODS

Data from 12,467 participants from the Natural Population Cohort of Northwest China: Ningxia Project was analyzed. Dietary intake was assessed using a validated semi-quantitative food frequency questionnaire. DAQS were calculated based on vitamins A, C, and E, zinc (Zn), and selenium (Se) intake. DTAC was estimated using the ferric-reducing ability of plasma assay. Logistic regression models were used to evaluate the associations of DAQS and DTAC with T2DM risk. Restricted cubic splines were used to assess potential non-linear relationships between DTAC and T2DM.

RESULTS

T2DM was observed in 1,238 (9.9%) participants. After adjusting for confounders, compared to the lowest tertiles (T1) of DAQS, the odds ratios (ORs) for T2DM were 1.03 (95% CI 0.82-1.30) in T2 and 0.85 (95% CI 0.68-1.06) in T3 (P = 0.010). Compared to T1, the ORs for T2DM in the highest T3 were 0.78 (95% CI 0.67-0.91, P-trend = 0.008) for vitamin A, 1.34 (95% CI 1.15-1.56, P-trend < 0.001) for vitamin E, 0.83 (95% CI 0.71-0.97, P-trend = 0.007) for Se, and 0.86 (95% CI 0.74-1.01, P-trend = 0.033) for Zn. Compared to the lowest quartile(Q1) of DTAC, the OR in the highest Q4 was 0.96 (95% CI 0.80-1.17, P-trend = 0.024) for T2DM. A non-linear relationship was observed between DATC and T2DM.

CONCLUSION

Higher DAQS and DATC were associated with a lower T2DM risk, suggesting that consuming antioxidant-rich foods may reduce the T2DM risk.

The association of dietary antioxidant index (DAI) with breast cancer among Iranian women

Recent studies have reported that dietary antioxidants can influence the risk of breast cancer (BC). Therefore, this study aimed to investigate the association of dietary antioxidant index (DAI) with BC among Iranian women. This case-control study was conducted on 180 women with breast cancer and 360 healthy women who were referred to the cancer clinic of Shohadaye Tajrish Hospital in Tehran, Iran. A 168-item validated food frequency questionnaire (FFQ) was used to assess dietary intake. The DAI score was calculated based on the intake of antioxidant vitamins and minerals derived from the FFQ. The control group had a significantly higher intake of vitamin D (1.79±1.56 vs. 1.05±0.84 μg/d; P=0.01) and lower intake of calorie (2315±1066 vs. 2737±925 kcal/d; P=0.01), carbohydrate (311±170 vs. 402±124 g/d; P=0.01), iron (15.4±12.1 vs. 19.7±6.4 mg/d; P=0.01), thiamine (1.5±0.7 vs. 2.3±0.9 mg/d; P=0.01), niacin (18.2±9.2 vs. 24.3±7.9 mg/d; P=0.01), folic acid (465±308.7 vs. 673±205.2 μg/d; P=0.01), and selenium (82.6±41.7 vs. 98.7±40.8 μg/d; P=0.01) compared to the case group. No significant association was found between DAI with breast cancer after adjustments for age. DAI had a negative association with breast cancer after additional adjustments for BMI, the number of pregnancies, duration of breastfeeding, menopause age, and total energy intake (OR: 0.91, 95% CI: 0.90-.93, and all P<0.001). The present study identified a negative association between DAI and the risk of BC, indicating the importance of antioxidants in preventing BC. Longitudinal studies should be conducted to confirm this association.

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.

Dietary total antioxidant capacity and the risk of developing asthenozoospermia: a hospital-based case-control study in China

STUDY QUESTION

Is dietary total antioxidant capacity (DTAC) associated with the odds of developing asthenozoospermia in Chinese men?

SUMMARY ANSWER

There is no statistically significant association between DTAC indices and the odds of developing asthenozoospermia.

WHAT IS KNOWN ALREADY

Both diet and oxidative stress may be related to sperm quality; however, few studies have investigated the association between DTAC and sperm quality.

STUDY DESIGN, SIZE, DURATION

This case-control study was conducted from June 2020 to December 2020. Those diagnosed with asthenozoospermia were assigned to the case group, whereas those with normal sperm parameters were assigned to the control group. Data from a total of 553 cases and 586 controls were included in the final analysis.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Men who had been referred to the infertility clinic of Shengjing Hospital of China Medical University were enrolled. Dietary intake was assessed using a validated food frequency questionnaire. DTAC was based on ferric-reducing ability of plasma (FRAP), total oxygen radical absorbance capacity (T-ORAC), hydrophilic oxygen radical absorbance capacity (H-ORAC), lipophilic oxygen radical absorbance capacity (L-ORAC), total phenolics (TP), total radical-trapping antioxidant parameter (TRAP), and Trolox equivalent antioxidant capacity (TEAC). Asthenozoospermia was defined according to the criteria published in the fifth edition of the World Health Organization laboratory manual for the examination and processing of human semen.

MAIN RESULTS AND THE ROLE OF CHANCE

No significant association was observed between the DTAC indices and the odds of asthenozoospermia after multivariable adjustment (T3 vs T1, odds ratio (OR) = 0.99, 95% CI: 0.73-1.33 for FRAP; OR = 1.05, 95% CI: 0.77-1.42 for T-ORAC; OR = 0.88, 95% CI: 0.65-1.18 for H-ORAC; OR = 0.98, 95% CI: 0.71-1.34 for L-ORAC; OR = 1.03, 95% CI: 0.76-1.39 for TP; OR = 1.18, 95% CI: 0.87-1.59 for TRAP; and OR = 1.15, 95% CI: 0.85-1.55 for TEAC). Both additive and multiplicative interaction analyses suggested that smoking might modify the association of T-ORAC with the odds of developing asthenozoospermia (relative excess risk due to interaction = 0.45, 95% CI: 0.07-0.83, attributable proportion due to interaction = 0.46, 95% CI: 0.07-0.84 for additive interaction; P = 0.033 for multiplicative interaction).

LIMITATIONS, REASONS FOR CAUTION

Recall bias and protopathic bias were inevitable in this retrospective case-control study. The estimation accuracy of the DTAC indices may have also affected the findings.

WIDER IMPLICATIONS OF THE FINDINGS

To the best of our knowledge, this is the first study to specifically investigate whether an association exists between DTAC and the odds of developing asthenozoospermia. Although no significant association was found, this study provides novel information pertaining to the fields of nutrition and human reproduction.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the JieBangGuaShuai Project of Liaoning Province (2021JH1/10400050), the Shengjing Hospital Clinical Research Project (M0071), and the Outstanding Scientific Fund of Shengjing Hospital (M1150). All authors have no competing interests to disclose.

TRIAL REGISTRATION NUMBER

N/A.

Association between urinary levels of 8-hydroxy-2-deoxyguanosine and F2a-isoprostane in male football players and healthy non-athlete controls with dietary inflammatory and antioxidant indices

Purpose

The relationship between the inflammatory and antioxidant potential of an athlete's diet and their oxidative biomarkers is an important area of investigation. Therefore, this study aimed to assess the excretion of 8-hydroxy-2-deoxyguanosine (8-OHdG) and F_2alpha-isoprostane (F_2a-IP) in the urine of male football players and healthy non-athlete controls. This study also aimed to examine the associations among the dietary inflammatory index (DII), the dietary total antioxidant capacity (DTAC), and the dietary phytochemical index (PI) with 8-OHdG and F_2a-IP.

Methods

In this descriptive-analytical study, 45 male football players and 45 healthy non-athletes, who were individually matched based on age and body mass index (BMI), were recruited from Shiraz City, Iran. Fasted urine samples were analyzed for 8-OHdG and F_2a-IP levels. Anthropometric measurements were performed, and body composition was assessed using a body composition analyzer. A valid food frequency questionnaire (FFQ) was used to calculate DII, DTAC, and PI scores. Data analysis was conducted using a generalized estimating equation (GEE) model.

Results

We found that 8-OHdG (β = -6.96), F_2a-IP (β = -82.58), and DII (β = -2.06) were significantly lower, while DTAC (β = 2.37) and PI (β = 0.084) were significantly higher in the football player group compared with the non-athlete group (P < 0.001 for all variables). In all participants, dietary indices were significantly associated with oxidative biomarkers. DII was positively associated with 8-OHdG (β = 2.25; P < 0.001) and F_2a-IP (β = 38.34; P < 0.001). Furthermore, negative associations between DTAC (β = -1.42; P < 0.001) and PI (β = -35.37; P < 0.001) with 8-OHdG were found. Moreover, DTAC (β = -17.34; P < 0.001) and PI (β = -428.11; P = 0.003) were negatively associated with F_2a-IP.

Conclusion

The results of this study highlighted the importance of a healthy diet in reducing oxidative stress among football athletes. The levels of urinary biomarkers for DNA and lipid oxidation were found to be lower in football players compared to non-athletes. This suggests that following an anti-inflammatory and antioxidant-rich diet may help reduce oxidative stress in these individuals.

The relationship of dietary antioxidant capacity with laboratory and anthropometric measurements in hemodialysis patients

Aim: Dietary antioxidant intake correlates with blood antioxidant content and protects against oxidative damage and related inflammatory complications. This study was conducted to examine the relationship between total antioxidant capacity of diet and effective factors with laboratory and anthropometric parameters in patients undergoing hemodialysis. Material and Method: The present case-control study consisted of 62 cases and 59 controls individuals who received hemodialysis treatment between the ages of 35-75. Dietary intake, sociodemographic data, medical history, and anthropometric measurements were collected from participants using a validated questionnaire. Results: Examining the association between dietary components and diet's total antioxidant capacity (dTAC) reveals a positive correlation between dietary protein (kg/avg), beta carotene (mcg/day), vitamin C (mg/day), vitamin E (mg/day), and polyunsaturated fatty acids (PUFA) (g/day) (p=0.002). The serum albumin, serum neutrophil to lymphocyte ratio and HDL-cholesterol have been reported to have a positive relationship with dTAC. And body mass ındex (BMI) and other anthropometric parameters were found to have a negative connection with dTAC (p=0.007). Conclusion: Total dietary antioxidant capacity is effective on anthropometric measurements and serum laboratory values. Increasing the antioxidant capacity of the diet in hemodialysis patients is important to prevent complications related to inflammation.

The association between dietary total antioxidant capacity and odds and severity of irritable bowel syndrome among Iranian adults: a cross-sectional study

Background

Little evidence is available in terms of the role of dietary antioxidants in the management of irritable bowel syndrome (IBS) disease. This study aimed to examine the association between dietary total antioxidant capacity (dTAC) and odds of IBS and its severity.

Methods

This cross-sectional study was conducted on 3,362 Iranian adults who were referred to health centers in Isfahan province, Iran. Participants' dietary intakes were collected using a semi-quantitative validated food frequency questionnaire (DS-FFQ). The dTAC was measured by the ferric-reducing antioxidant power (FRAP) method. Multivariable binary or ordinal logistic regression analyses were performed to estimate any associations between dTAC and odds of IBS, IBS severity, and IBS subtypes.

Results

The average age and BMI of the participants and dTAC score were 36.3 ± 7.87 year, 24.9 ± 3.82 kg/m2. The prevalence of IBS, IBS with constipation (IBS-C), IBS with diarrhoea (IBS-D), mixed IBS (IBS-M), and un-subtyped IBS (IBS-U) were 22.2, 7.5, 4.6, 3.8, and 6.2%, respectively. In crude and adjusted models, the results did not show any significant association between dTAC and odds of IBS among whole and gender-age stratified populations. Being in the third compared with the first tertile of dTAC was not also significantly associated with odds of IBS severity. Besides, there were no significant associations between dTAC and odds of IBS-C, IBS-D, IBS-M, and IBS-U.

Conclusion

This study indicates that dTAC may not be associated with the odds of IBS and its severity even after stratification for gender and body mass index.

Do Intestinal Unicellular Parasites Have a Role in the Inflammatory and Redox Status among the Severely Obese?

The diagnosis of obesity comprises subjects with totally different phenotypes and metabolic profiles. Systemic inflammation and oxidative stress derived from the white adipose tissue are suggested as the link between this disease and the development of insulin resistance and metabolic comorbidities. The presence of unicellular eukaryotic parasites colonizing the human gut ecosystem is a common circumstance, and yet their influence on the inflammatory and redox status of the obese host has not been assessed. Herein, a set of inflammatory and redox biomarkers were assessed together with a parasitological analysis of 97 severely obese subjects. Information was also collected on insulin resistance and on the antioxidant composition of the diet. The global prevalence of intestinal unicellular parasites was 49.5%, with Blastocystis sp. the most prevalent protozoan found (42.3%). Colonized subjects displayed a higher total antioxidant capacity and a trend towards higher extracellular superoxide dismutase activity, regardless of their insulin resistance status, along with lower reduced glutathione/oxidized glutathione (GSH/GSSG) ratios in plasma in the insulin-resistant subgroup. No changes in malondialdehyde levels, or in inflammatory cytokines in plasma, were found in regard to the colonization status. In conclusion, enteric eukaryotic unicellular parasites may play an important role in modulating the antioxidant defenses of an obese host, thus could have beneficial effects with respect to the development of systemic metabolic disorders.

Postprandial changes of oxidative stress biomarkers in healthy individuals

Food consumption induces oxidative stress in humans, but the changes in oxidative stress levels after a regular meal are still unclear. We conducted an experimental study on 20 healthy volunteers (10 males, 10 females), who matched in age (±2 years). They were given a regular diet (total energy of 704 kcal, which contains 75 g of carbohydrates, 35 g of protein, and 29 g of lipids) at 11:30 a.m. after a fast of over 12 h. We collected 6-repeated measures of venous blood samples at 2-h intervals via heparin anticoagulant tubes immediately after the meal (indicated as “0” h) and up to 10 h post-consumption. Biomarkers included plasma fluorescent products, plasma malondialdehyde, plasma total antioxidant capacity, and plasma superoxide dismutase. FlOPs were measured at three excitation/emission wavelengths (FlOP_320, FlOP_360, and FlOP_400). The average age and BMI for the twenty participants were 22.70 ± 1.98 years and 20.67 ± 2.34 kg/m², respectively. Within 10 h after the meal, the overall trend of FlOPs were generally similar. There was no evidence of dose response for any of the three FlOPs (all P > 0.05). However, levels of MDA decreased with the time of fasting (P_linear and P_quadratic < 0.05), with the biggest decrease occurring between 0 and 2 h post-meal. The overall trend of T-AOC and SOD levels also decreased with fasting time (P_linear and P_quadratic < 0.05), though an increase was observed between 0 and 2 h following consumption. Levels of MDA, T-AOC, and SOD but not FlOPs, decreased with fasting time.

Interaction between Apo A-II -265T > C polymorphism and dietary total antioxidant capacity on some oxidative stress and inflammatory markers in patients with type 2 diabetes mellitus

This work aims to examine the interaction between apo A2 (Apo A-II) -265T > C SNP and dietary total antioxidant capacity (DTAC) on inflammation and oxidative stress in patients with type 2 diabetes mellitus. The present cross-sectional study included 180 patients (35-65 years) with identified Apo A-II genotype. Dietary intakes were assessed by a FFQ. DTAC was computed using the international databases. IL-18 (IL18), high-sensitivity C-reactive protein (hs-CRP), pentraxin (PTX3), serum total antioxidant capacity (TAC), superoxide dismutase (SOD) activity and 8-isoprostaneF2α (PGF2α) markers were obtained according to standard protocols. General linear model was used to evaluate the interaction. The interaction of gene and DTAC (P_FRAP = 0·039 and P_ORAC = 0·042) on PGF2α level was significant after adjusting for confounders. A significant interaction was observed on IL18 level (P_ORAC = 0·018 and P_FRAP = 0·048) and SOD (P_TEAC = 0·037) in obese patients. Among patients whose DTAC was higher than the median intake, the levels of hs-CRP and PGF2α were significantly higher only in individuals with CC genotype. Serum TAC (P_FRAP = 0·030, P_ORAC = 0·049) and SOD were significantly lower in the CC genotype. There was a favourable relationship between the high-DTAC and SOD (obese: P_TEAC = 0·034, non-obese: P_FRAP = 0·001, P_TRAP < 0·0001, P_TEAC = 0·003 and P_ORAC = 0·001) and PGF2α (non-obese: P_ORAC = 0·024) in T-allele carriers. The rs5082 SNP interacts with DTAC to influence several cardiometabolic risk factors. Also, we found dietary recommendations for antioxidant-rich foods intake might be useful in the prevention of diabetes complications in the T carrier more effectively than the CC genotype. Future large studies are required to confirm these results.

The Effects of Eggs in a Plant-Based Diet on Oxidative Stress and Inflammation in Metabolic Syndrome

We recently reported that the inclusion of whole eggs in plant-based diets (PBD) increased plasma choline, lutein, and zeaxanthin in individuals with metabolic syndrome (MetS). The objective of the current study was to evaluate whether this dietary pattern would protect against oxidative stress and low-grade inflammation, two common characteristics of MetS. We recruited 24 men and women with MetS, who, after following a PBD for 2 weeks (baseline), were randomly allocated to consume either two whole eggs with 70 g of spinach/day (EGG) or the equivalent amount of egg substitute with spinach (SUB) as breakfast for 4 weeks. After a 3-week washout, they were allocated to the alternate breakfast. We measured biomarkers of oxidation and inflammation at baseline and at the end of each intervention. Tumor necrosis factor-alpha, interleukin-6, monocyte protein attractant-1, liver enzymes, and C-reactive protein, as well as total antioxidant capacity, paraoxonase-1 (PON-1) activity, and other biomarkers of oxidation were not different at the end of EGG or SUB or when compared to baseline. However, plasma malondialdehyde (MDA) concentrations were lower (p < 0.05) during the EGG and baseline compared to SUB. In addition, the increases in dietary lutein and zeaxanthin previously observed had a strong positive correlation with PON-1 activity (r = 0.522, p < 0.01) only during the EGG period, whereas plasma zeaxanthin was negatively correlated with MDA (r = −0.437, p < 0.01). The number of participants with MetS was reduced from 24 during screening to 21, 13, and 17 during the BL, EGG, and SUB periods, respectively, indicating that eggs were more effective in reversing the characteristics of MetS. These data suggest that adding eggs to a PBD does not detrimentally affect inflammation or oxidative stress; on the contrary, eggs seem to provide additional protection against the biomarkers that define MetS.

Adolescents' dietary polyphenol intake in relation to serum total antioxidant capacity: the HELENA study

We evaluated the association between intake of total polyphenols, polyphenol classes and the 10 most consumed individual polyphenols with serum total antioxidant capacity (TAC) in 749 European adolescents (53% girls; 15% overweight; 12.5-17.5 years-old) from the cross-sectional HELENA study of 2006-2007. Dietary polyphenol intake was calculated from two non-consecutive 24-h recalls matched with the Phenol-Explorer database. Multilevel linear models examined the associations between dietary polyphenols and TAC. Polyphenol intake was rather low (median = 321mg/day; p25 = 158; p75 = 536) and TAC was comparable to other literature findings (median = 1.57 mmol/L; p25 = 1.45; p75 = 1.74). Total polyphenol intake, polyphenol classes and the top 10 compounds were not associated with TAC in a linear, quadratic or cubic way in partially or fully confounder-adjusted models. A direct anti-oxidative effect of dietary polyphenol intake was not observed in European adolescents. Polyphenol biomarkers and additional antioxidant measures are needed in future prospective studies to confirm these results.

Antioxidant properties of anthocyanins and their mechanism of action in atherosclerosis

Atherosclerosis develops due to lipid accumulation in the arterial wall and sclerosis as result of increased hyperlipidemia, oxidative stress, lipid oxidation, and protein oxidation. However, improving antioxidant status through diet may prevent the progression of atherosclerotic cardiovascular disease. It is believed that polyphenol-rich plants contribute to the inverse relationship between fruit and vegetable intake and chronic disease. Anthocyanins are flavonoid polyphenols with antioxidant properties that have been associated with reduced risk of cardiovascular disease. The consumption of anthocyanins increases total antioxidant capacity, antioxidant defense enzymes, and HDL antioxidant properties by several measures in preclinical and clinical populations. Anthocyanins appear to impart antioxidant actions via direct antioxidant properties, as well as indirectly via inducing intracellular Nrf2 activation and antioxidant gene expression. These actions counter oxidative stress and inflammatory signaling in cells present in atherosclerotic plaques, including macrophages and endothelial cells. Overall, anthocyanins may protect against atherosclerosis and cardiovascular disease through their effects on cellular antioxidant status, oxidative stress, and inflammation; however, their underlying mechanisms of action appear to be complex and require further elucidation.

Healthy Eating Index-2015 and Dietary Total Antioxidant Capacity as Predictors of Prediabetes: A Case-Control Study

BACKGROUND

The overall dietary quality, as well as the dietary total antioxidant capacity (DTAC), deserves central attention in the management of borderline high glucose levels since nonpharmacological strategies are imperative in this regard. Thus, we aimed to investigate the association between prediabetes with dietary quality and DTAC.

METHODS

A case-control study was conducted on 49 patients with prediabetes and 98 controls. Demographics, anthropometric measures, and fasting blood glucose levels of all participants were obtained. Participants completed a validated 80-item food frequency questionnaire (FFQ). DTAC scores were generated using FFQ data, and Healthy Eating Index-2015 (HEI-2015) was used as a diet quality index. The lowest tertile of HEI-2015 and DTAC was considered as the reference category, and logistic regression was used to estimate the relationship between prediabetes with HEI-215 and DTAC.

RESULTS

Mean age and body mass index of participants were 47.42 ± 15.98 years and 27.90 ± 4.96 kg/m2. Patients with prediabetes had lower DTAC scores when compared to controls (11.86 ± 5.77 and 17.81 ± 12.08, P = 0.01). There was a significant inverse association between the highest tertile of the DTAC score when compared with the lowest tertile in crude (OR = 0.11; 95% CI: 0.03-0.43), age-adjusted (OR = 0.13; 95% CI: 0.03-0.48), and fully adjusted (OR = 0.09; 95% CI: 0.02-0.53) models. In contrast, there was no difference between HEI-2015 in patients with prediabetes when compared to controls (74.41 ± 8.91 and 74.41 ± 9.35, respectively; P = 0.85). Correspondingly, no difference was observed between the highest tertile of the HEI-2015 score when compared with the lowest tertile in crude (OR = 1.23; 95% CI: 0.53-2.86), age-adjusted (OR = 1.17; 95% CI: 0.48-2.82), and fully adjusted (OR = 1.53; 95% CI: 0.56-4.16) models.

CONCLUSION

This study demonstrates a clear association between prediabetes with less DTAC, but not with HEI-2015.

Higher dietary total antioxidant capacity (TAC) reduces the risk of cardio-metabolic risk factors among adults: An updated systematic review and meta-analysis

Background: Numerous studies have revealed the protective role of dietary antioxidants against hypertension and diabetes. In the current systematic review and meta-analysis, we evaluated the possible role of dietary total antioxidant capacity (TAC) against metabolic parameters in the adult population. Methods: A literature search of authentic electronic resources including PubMed, Scopus, Web of Sciences, and Cochrane had been performed to retrieve the qualified observational studies that reported the mean plus/minus the SD for the parameter in subjects of the highest versus lowest dietary TAC categories up to July 2020. Results: Totally, the number of included studies was 13 for fasting blood sugar (FBS), 12 for systolic blood pressure (SBP), and 12 for diastolic blood pressure (DBP), with the participants' number of 26349. The results of the current study showed that being at highest category of TAC significantly reduces serum FBS (WMD: -2.381; CI: -3.445, -1.316; P<0.001), SBP (WMD: -1.080; CI: -1.458, -0.701; P<0.001) and DBP (WMD: -0.854; CI: -1.655, -0.052; P<0.001), while no significant difference in the serum insulin, HOMA-IR values, prevalence of type 2 diabetes (T₂DM) (P=0.37) and hypertension (HTN) (P=0.09) was observed. Subgroup analysis revealed the geographical location, dietary assessment tool, sample size, and gender as possible sources of heterogeneity. Conclusion: Higher intake of dietary TAC was associated with reduced SBP, DBP, and FBS in the current observational studies of this meta-analysis. These findings further confirm the clinical importance of dietary antioxidants in the prevention of different metabolic disorders.

The Comparison of Total Phenolics, Total Antioxidant, and Anti-Tyrosinase Activities of Korean Sargassum Species

Sargassum species, a group of marine brown algae consumed in Asian countries, have shown various health benefits, such as improving the conditions of cardiovascular disease, osteoarthritis, and hypopigmentation. Also, these benefits are associated with their phenolic content and strong antioxidant capacities. However, the antioxidant capacities of different Sargassum species had not been thoroughly explored and compared. Thus, this study aimed to compare the total phenolic contents, total flavonoid contents, total antioxidant capacities, and anti-tyrosine activity of eleven Sargassum species harvested off the Korean coast. The results revealed that the total phenolic content (from 20.57 to 88.97 mg gallic acid equivalent/g dry weight (dw)), flavonoid content (from 22.08 to 82.33 mg quercetin equivalent/g dw), anti-tyrosinase activity (from 13.30 to 126.30 mg kojic acid equivalent/dw), and antioxidant capacities of the 11 Sargassum species had wide ranges. Among them, S. miyabei Yendo and S. hemiphyllum showed the highest total antioxidant capacities while S. miyabei Yendo exhibiting the highest total phenolic and flavonoid contents. The highest anti-tyrosinase activity was seen in S. fillicinum and S. yendoi. Sargahydroqunoic acid and sargachromanol, two alga-derived meroterpenoid compounds with strong antioxidant activity, were detected and quantified in S. miyabei Yendo and S. serratifolium. Our findings guarantee further investigation of the health benefits of Sargassum species and maximize the commercial usage of these species.

Validation of Dietary Antioxidant Index (DAI) and investigating the relationship between DAI and the odds of gastric cancer

BACKGROUND

Gastric cancer (GC) incidence and mortality are rapidly growing worldwide. It is estimated that more than 1,000,000 new cases are diagnosed each year, and more than 78,000 people lose their lives due to GC. The association between dietary antioxidants and GC has been shown in some studies. However, because of the discrepancy between the findings and the lack of a valid indicator, it seems necessary to design and validate the Dietary Antioxidant Index (DAI) to examine the diet's total antioxidant content. The present study aimed to survey the validity of DAI and its association with the odds of GC.

METHODS

In this hospital-based case-control study, 82 patients with GC and 95 healthy controls were examined. We used a 168-item food frequency questioner to assess dietary intakes. The DAI was calculated based on the intake of vitamin A, C, E, and selenium, manganese, and zinc. We standardized each of the six vitamins and minerals by subtracting the global mean and dividing by the global standard deviation to calculate DAI. We then calculated the DAI by summing up the standardized intakes of these vitamins and minerals of the individuals with equal weight.

RESULTS

We observed a significant correlation between DAI and total antioxidant capacity (TAC) after controlling for age, body mass index (BMI), energy intake, smoking and fasting blood sugar, education, total fat intake, helicobacter pylori infection, total cholesterol, and saturated fatty acid (SFA) intakes. Results obtained from modeling DAI as a continuous variable in relation to GC showed a negative association after adjustment for age and in the multivariable analysis (OR = 0.64, CI = 0.43-0.95).

CONCLUSION

DAI is a valid indicator of dietary antioxidants assessments, and it can be used as a predictor of antioxidant status due to its correlation with serum antioxidant levels. The results showed that dietary antioxidants have a significant relationship with GC, which indicates the importance of antioxidants in this cancer's etiology.

Nutrigenetics of antioxidant enzymes and micronutrient needs in the context of viral infections

Sustaining adequate nutritional needs of a population is a challenging task in normal times and a priority in times of crisis. There is no 'one-size-fits-all' solution that addresses nutrition. In relevance to the COVID-19 (coronavirus disease 2019) pandemic crisis, viral infections in general and RNA viruses in particular are known to induce and promote oxidative stress, consequently increasing the body's demand for micronutrients, especially those related to antioxidant enzymic systems, thus draining the body of micronutrients, and so hindering the human body's ability to cope optimally with oxidative stress. Common polymorphisms in major antioxidant enzymes, with world population minor allele frequencies ranging from 0·5 to 50 %, are related to altered enzymic function, with substantial potential effects on the body's ability to cope with viral infection-induced oxidative stress. In this review we highlight common SNP of the major antioxidant enzymes relevant to nutritional components in the context of viral infections, namely: superoxide dismutases, glutathione peroxidases and catalase. We delineate functional polymorphisms in several human antioxidant enzymes that require, especially during a viral crisis, adequate and potentially additional nutritional support to cope with the pathological consequences of disease. Thus, in face of the COVID-19 pandemic, nutrition should be tightly monitored and possibly supplemented, with special attention to those carrying common polymorphisms in antioxidant enzymes.

Redox Status, Dose and Antioxidant Intake in Healthcare Workers Occupationally Exposed to Ionizing Radiation

The purpose of this study was to evaluate the relationship between blood redox status, dose and antioxidant dietary intake of different hospital staff groups exposed to low doses of ionizing radiation (LDIR) (Interventional Radiology and Cardiology, Radiation Oncology, and Nuclear Medicine) and non-exposed. Personal dose equivalent (from last year and cumulative), plasma antioxidant markers (total antioxidant capacity, extracellular superoxide dismutase activity, and glutathione/oxidized glutathione ratio), oxidative stress markers (nitrites and nitrates, and lipid peroxidation) and dietary intake (antioxidant capacity using ORAC values) were collected and analyzed from 28 non-exposed healthcare workers and 42 healthcare workers exposed to LDIR. Hospital staff exposed to LDIR presented a redox imbalance in blood that seems to correlate with dose. Workers from the Nuclear Medicine Unit were the most affected group with the lowest value of plasma antioxidant response and the highest value of plasma thiobarbituric acid reactive substances, TBARS (indicator of lipid peroxidation) of all four groups. Cumulative personal dose equivalent positively correlated with nitrites and negatively correlated with total antioxidant capacity in blood. The diet of healthcare workers from Nuclear Medicine Unit had higher ORAC values than the diet of non-exposed. Therefore, occupational exposure to LDIR, especially for the Nuclear Medicine Unit, seems to produce an imbalanced redox status in blood that would correlate with cumulative personal dose equivalent.

Dietary total antioxidant capacity (TAC), general and central obesity indices and serum lipids among adults: An updated systematic review and meta-analysis

Background: In the present meta-analysis, we aimed to summarize the relationship between dietary total antioxidant capacity (TAC), general and central obesity indices and lipid profile in adult population. Methods: The electronic databases of Web of Sciences, PubMed, Scopus and Cochrane library were searched for relevant studies from inception to October 2019. The effect size was indicated as weighted mean difference (WMD) and 95% confidence intervals (CI) by using random effects model. The I² index and Cochran's Q-test were used for evaluating heterogeneity. Results: From 2,469 studies identified, thirty-four studies (nineteen cross-sectional studies, thirteen cohort studies, two case-control studies) were included in the meta-analysis. According to our results, higher categories of TAC were associated with significantly lower serum triglyceride concentartions (TG; WMD: -7.58; CI: -11.42, -3.75; P < 0.001) and waist circumference (WC; WMD: -1.17; 95% CI: -1.47, -0.87; P < 0.001); while no significant change in body mass index (BMI; WMD: -0.17; 95% CI: -0.35, 0.01; P = 0.12), high density lipoprotein cholesterol (HDL-C; WMD: 0.61; 95% CI: -0.16, 1.40; P = 0.12), low density lipoprotein cholesterol (LDL-C; WMD: 1.34; 95% CI: -0.61, 3.30; P = 0.17) and total cholesterol (TC; WMD: 1.19; 95% CI: -1.46, 3.855; P = 0.37) was reported. Conclusion: Higher dietary TAC was related to reduced prevalence of central obesity, reduced WC and TG concentrations in the current meta-analysis. Moreover, subgroup analysis showed that TAC measurement index, geographical area, dietary assessment tool, health status and gender were potential sources of heterogeneity.

Dietary Total Antioxidant Capacity and Risk of Non-Alcoholic Fatty Liver Disease: A Case-Control Study

BACKGROUND

Dietary total antioxidant capacity (DTAC) has been proposed as a tool for assessing the intake of antioxidants. This study aimed to assess whether a relationship exists between dietary total antioxidant capacity (TAC) and the odds of NAFLD.

STUDY DESIGN

A case-control study.

METHODS

In this age-and sex-matched case-control study in 2019, patients with NAFLD and healthy controls were recruited from a hospital clinic. All participants completed a validated 168-item food frequency questionnaire, the results of which were subsequently used to generate dietary TAC. Oxygen radical absorbance capacity values were used to calculate dietary TAC.

RESULTS

Altogether, 225 patients with NAFLD and 450 healthy controls were enrolled. Participants with NAFLD had a higher mean weight, BMI, energy (P<0.050), and lower physical activity and DTAC scores (P<0.050) than the control group. In an adjusted model, participants who were in the highest quartile of dietary TAC had a lower risk of NAFLD (odds ratio 0.78, 95% CI: 0.67, 0.91).

CONCLUSION

A high DTAC was related to a decreased risk of NAFLD. Suggest the intake of a diet with high antioxidant capacity is significant at preventing NAFLD. Increasingly itemized investigations in design of randomized control trials require to reveal more insight into these results.

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.

Plasma Non-Enzymatic Antioxidant Capacity (NEAC) in Relation to Dietary NEAC, Nutrient Antioxidants and Inflammation-Related Biomarkers

(1) Background: Little is known about the interlinkages between dietary and plasma non-enzymatic antioxidant capacity (D-NEAC and P-NEAC, respectively) and the body’s antioxidant and inflammation response. Our aim was to explore these associations in 210 participants from two Spanish European Prospective Investigation into Cancer and Nutrition (EPIC) centers. (2) Methods: D-NEAC was estimated using published NEAC values in food. P-NEAC and total polyphenols (TP) were quantified by FRAP (ferric-reducing antioxidant power), TRAP (total radical-trapping antioxidant parameter), TEAC-ABTS (trolox equivalent antioxidant capacity-Azino Bis Thiazoline Sulfonic), ORAC (oxygen radical absorbance capacity) and Folin–Ciocalteu assays. Nutrient antioxidants (carotenes, α-tocopherol, ascorbic acid, retinol, uric acid, Q9 and Q10 coenzymes) and inflammation markers (IL-6, IL-8, CRP, TNF-α, PAI-I, resistin and adiponectin) were also analyzed. Spearman correlation and linear regression analyses were performed in association analyses. Analyses were stratified by covariates and groups were defined using cluster analysis. (3) Results: P-FRAP was correlated with D-NEAC, and significantly associated with P-NEAC in multivariate adjusted models. P-FRAP levels were also significantly associated with plasma antioxidants (log2 scale: TP β = 0.26; ascorbic acid β = 0.03; retinol β = 0.08; α-tocopherol β = 0.05; carotenes β = 0.02; Q10 β = 0.06; uric acid β = 0.25), though not with inflammation-related biomarkers. Different profiles of individuals with varying levels of P-NEAC and biomarkers were found. (4) Conclusions: P-NEAC levels were to some extent associated with D-NEAC and plasma antioxidants, yet not associated with inflammation response.

Systemic anti-oxidant capacity is inversely correlated with systolic blood pressure and pulse pressure in children with obesity

BACKGROUND AND AIMS

Oxidative stress leading to endothelial dysfunction is a candidate driver of obesity-related hypertension. We aimed to assess whether the total anti-oxidant capacity (TAC) was associated with blood pressure in children/adolescents with obesity.

METHODS AND RESULTS

One hundred and fifty-two children/adolescents with obesity (79 boys; age 11.9+/-2.5 years) underwent blood drawing for the assessment of TAC, lipids and HOMA-IR. Blood pressure was measured and classified according to the latest American Academy of Pediatrics Guidelines. Serum TAC was measured by a commercial kit (Sigma-Aldrich). The average TAC was 1.11+/-0.4 mMol/Trolox equivalents. Systolic blood pressure was predicted by TAC (B = -5.8, p = 0.003), z-BMI (B = 2.39, p = 0.008), height [cm] (B = 0.38, p < 0.001) and diastolic blood pressure (B = 0.56, p < 0.001). Diastolic blood pressure was predicted by age [years] (B = 0.58, p = 0.001), log-HOMA-IR (B = 3.0, p = 0.002), and systolic blood pressure (B = 0.26, p < 0.001), but not by TAC. The pulse pressure was predicted only by TAC (B = - 6.6, p = 0.002), and height [cm] (B = 0.42, p < 0.001). Overall "elevated blood pressure + hypertension" or hypertension alone were not associated with TAC. However, systolic "elevated blood pressure + hypertension" was associated with TAC (OR = 0.4 [0.1-0.9], p = 0.037), and z-BMI (OR = 2.1 [1.3-3.6], p = 0.004).

CONCLUSION

The systemic anti-oxidant capacity is inversely associated with systolic blood pressure and pulse pressure in children and adolescents with obesity.

Dietary total antioxidant capacity is positively associated with muscular strength in cirrhotic outpatients: a cross-sectional study

BACKGROUND

Cirrhosis is the end-stage of progressive fibrosis, in which oxidative stress and inflammation-related pathways can modulate the cellular and tissue events involved in the pathogenesis of liver fibrosis. Dietary intake of antioxidants has been suggested to protect against oxidative damage and related clinical complications. The present study aimed to investigate the potential association of the dietary total antioxidant capacity (dTAC) with anthropometric, functional and biochemical markers, as well as the severity of the disease, in cirrhotic outpatients.

METHODS

Sixty-two outpatients (38 men and 24 women) with a mean (SD) age of 59.1 (9.9) years were evaluated. Dietary TAC was estimated from a food frequency questionnaire. Aetiology and severity of liver cirrhosis, lifestyle characteristics, occurrence of comorbidities and oedema, and anthropometric, functional and biochemical markers were all assessed.

RESULTS

Cirrhotic outpatients with higher dTAC also had higher values of the hand-grip strength (P = 0.029) and arm muscle area (P = 0.027). After adjusting by sex, age, smoking and alcohol intake, the addition of 1 mmol day^-1 of dTAC contributed to increase 0.552 kg f^-1 in hand-grip strength (P < 0.05). The addition of one mmol day^-1 of dTAC contributed to an arm muscle area increase 0.565 cm² (P < 0.05) on average.

CONCLUSIONS

The dTAC was positively associated with hand-grip strength and arm muscle area in cirrhotic outpatients. The implications of the present study are important in clinical practice because a diet rich in antioxidants may be an ally in the control of excessive reactive oxygen species production in cirrhotic outpatients with repercussion on muscle mass and strength.

Dietary Total Antioxidant Capacity and the Risk of Chronic Kidney Disease in Patients With Type 2 Diabetes: A Nested Case-Control Study in the Tehran Lipid Glucose Study

OBJECTIVE

Dietary total antioxidant capacity (DTAC) has been hypothesized as being involved in health promotion and disease prevention. However, data about the association of the DTAC (as estimated by ferric reducing antioxidant power) with diabetes chronic complications are scarce. Therefore, the aim of this study was to determine the associations between the DTAC and chronic kidney disease (CKD) risk in subjects with type 2 diabetic.

METHODS

The present case-control study consisted of 210 (102 cases and 108 controls) patients with type 2 diabetic who were participants of the phase 5 Tehran Lipid and Glucose Study and were classified based on their CKD status. DTAC was estimated based on the ferric reducing antioxidant power of selected foods. Dietary intake, sociodemographic data, medical history, and anthropometric measurements were collected from participants using a validated questionnaire.

RESULTS

The mean DTAC value, as well as total calorie intake, did not show significant differences between cases and controls.

CONCLUSION

No significant association was found between DTAC and CKD in patients with type 2 diabetic. Further studies are needed to confirm the effects of DTAC on the risk of CKD.

Blood-based redox-signature and their association to the cognitive scores in MCI and Alzheimer's disease patients

Oxidative stress plays a pivotal and early role in the pathophysiology of Alzheimer's disease (AD). There is convincing evidence that oxidative alterations in AD and in mild cognitive impairment (MCI) patients are not limited to the brain but are extended to the blood compartment. However, the oxidative pattern in plasma is still inconclusive. Moreover, their potential association with the clinical scores MMSE (Mini-Mental State Examination) and MoCA (Montreal Cognitive Assessment) is poorly investigated. The aim of our study was to establish a pattern of blood-based redox alterations in prodromal AD and their evolution during the progression of the disease. Our results showed a reduction in the total antioxidant capacity (TAC) and an increase of the stress-response proteins apolipoprotein J (ApoJ) and Klotho in MCI subjects. For the first time, we evidenced circulating-proteasome activity. We found that the alteration of the circulating-proteasome activity is associated with the accumulation of oxidized proteins in plasma form early AD. Interestingly, the TAC, the levels of vitamin D and the activity of proteasome were positively associated to the clinical scores MMSE and MoCA. The levels of protein carbonyls and of ApoJ were negatively associated to the MMSE and MoCA scores. The levels of apolipoprotein D (ApoD) were not different between groups. Interestingly, the receiver operating characteristic (ROC) curves analysis indicated that these redox markers provide a fair classification of different groups with high accuracy. Overall, our results strengthen the notion that some specific oxidative markers could be considered as non-invasive blood-based biomarkers for an early MCI diagnosis and AD progression.