Acute effect of nut consumption on plasma total polyphenols, antioxidant capacity and lipid peroxidation

Food and Food Waste Antioxidants: Could They Be a Potent Defence against Parkinson's Disease?

Oxidative stress, an imbalance between reactive oxygen species (ROS) and endogenous antioxidants, plays an important role in the development of neurodegenerative diseases, including Parkinson's. The human brain is vulnerable to oxidative stress because of the high rate of oxygen that it needs and the high levels of polyunsaturated fatty acids, which are substrates of lipid peroxidation. Natural antioxidants inhibit oxidation and reduce oxidative stress, preventing cancer, inflammation, and neurodegenerative disorders. Furthermore, in the literature, it is reported that antioxidants, due to their possible neuroprotective activity, may offer an interesting option for better symptom management, even Parkinson's disease (PD). Natural antioxidants are usually found in several foods, such as fruits, vegetables, meat, fish, and oil, and in food wastes, such as seeds, peels, leaves, and skin. They can help the system of endogenous antioxidants, protect or repair cellular components from oxidative stress, and even halt lipid, protein, and DNA damage to neurons. This review will examine the extent of knowledge from the last ten years, about the neuroprotective potential effect of natural antioxidants present in food and food by-products, in in vivo and in vitro PD models. Additionally, this study will demonstrate that the pool of dietary antioxidants may be an important tool in the prevention of PD and an opportunity for cost savings in the public health area.

Applications of Plant Bioactive Compounds as Replacers of Synthetic Additives in the Food Industry

According to the Codex Alimentarius, a food additive is any substance that is incorporated into a food solely for technological or organoleptic purposes during the production of that food. Food additives can be of synthetic or natural origin. Several scientific evidence (in vitro studies and epidemiological studies like the controversial Southampton study published in 2007) have pointed out that several synthetic additives may lead to health issues for consumers. In that sense, the actual consumer searches for "Clean Label" foods with ingredient lists clean of coded additives, which are rejected by the actual consumer, highlighting the need to distinguish synthetic and natural codded additives from the ingredient lists. However, this natural approach must focus on an integrated vision of the replacement of chemical substances from the food ingredients, food contact materials (packaging), and their application on the final product. Hence, natural plant alternatives are hereby presented, analyzing their potential success in replacing common synthetic emulsifiers, colorants, flavorings, inhibitors of quality-degrading enzymes, antimicrobials, and antioxidants. In addition, the need for a complete absence of chemical additive migration to the food is approached through the use of plant-origin bioactive compounds (e.g., plant essential oils) incorporated in active packaging.

The Immunomodulatory Effects of a 6-Month Extra Virgin Olive Oil Intervention on Monocyte Cytokine Secretion and Plasma Cytokine Levels in Dyslipidemic and Post-Infarct Patients: A Clinical Pilot Study

Atherosclerosis is an immuno-inflammatory process underlying cardiovascular diseases. One of the main actors of this inflammation is monocytes, with the switch in their phenotypes and irregularities in their cytokine production.

OBJECTIVE

This study was aimed to investigate the nutraceutical potential of extra virgin olive oil (EVOO) on the inflammatory status of monocytes in participants showing different levels of cardiovascular risk.

METHODS

43 participants 65-85 years old were recruited including 14 healthy, 12 dyslipidemic patients with hypercholesterolemia recently diagnosed, and 17 post-infarct patients. Participants from all groups were supplemented with EVOO (25 mL/day) for 6 months. IL-1β, IL-6, IL-10, TNF-α cytokine production, and monocyte phenotypes were investigated both at quiescent and at stimulated state by flow cytometry.

RESULTS

At the baseline (pre-intervention), dyslipidemic patients, compared to healthy and post-infarct participants, showed monocytes in an inflammatory state characterized by a significantly weaker IL-10 production. Our results do not show a significant modulation of the phenotype or IL-10, IL-6, and TNF-α production following a 6-month EVOO intake whether at quiescence or under stimulation. However, IL-1β is significantly increased by the intervention of EVOO in post-infarct patients. Paradoxically after the 6-month intervention, monocytes from dyslipidemic patients showed a significantly decreased secretion of IL-1β under LPS stimulation despite the increase observed at basal state.

CONCLUSION

Our results show that 6-month EVOO intervention did not induce a monocyte phenotypic change or that this intervention significantly modifies cytokine production.

Effects of Mixed Nut Consumption on Blood Glucose, Insulin, Satiety, and the Microbiome in a Healthy Population: A Pilot Study

Nuts contain many health-promoting nutrients, fiber, and phytochemicals. Nut consumption has been reported to improve several chronic disease risk factors. Most studies to date have investigated single variety nut consumption. A nut mixture may offer a more diverse array of nutrients over single variety nuts. The primary outcome of this study was to examine the effects of mixed nut consumption on postprandial glucose, insulin, and satiety in healthy young adults. Exploratory outcomes include the effects of daily nut consumption on stool microbiome and bowel movement patterns. Twenty participants were randomized to consume either 42 g of mixed nuts or 46 g of potato chips daily for 3 weeks. Mixed nut consumption did not alter postprandial blood glucose and insulin, while potato chip consumption increased glucose and insulin (P < .05). There were no significant differences in fasting blood glucose or insulin for either snack after 3 weeks of daily consumption. Both snacks increased satiety while there were no significant differences in body weight, body fat, blood pressure, waist-to-hip ratio, or anxiety. After 3 weeks of snack consumption, both groups significantly reduced straining during bowel movements while the mixed nut group slightly increased stool amount. There were no significant changes in microbiome composition for either group; however, there was a nonsignificant trend toward increased Firmicutes to Bacteroidetes ratio in the potato chip group and an opposite trend in the mixed nut group. The results of this study suggest that mixed nuts are a healthy alternative for blood sugar control. The study was registered at ClinicalTrials.gov, Number: NCT03375866.

Effect of Walnut Supplementation on Dietary Polyphenol Intake and Urinary Polyphenol Excretion in the Walnuts and Healthy Aging Study

Among all tree nuts, walnuts contain the highest total polyphenols by weight. This secondary data analysis examined the effect of daily walnut supplementation on the total dietary polyphenols and subclasses and the urinary excretion of total polyphenols in a free-living elderly population. In this 2-year prospective, randomized intervention trial (ID NCT01634841), the dietary polyphenol intake of participants who added walnuts daily to their diets at 15% of daily energy were compared to those in the control group that consumed a walnut-free diet. Dietary polyphenols and subclasses were estimated from 24 h dietary recalls. Phenolic estimates were derived from Phenol-Explorer database version 3.6. Participants in the walnut group compared to the control group had a higher intake of total polyphenols, flavonoids, flavanols, and phenolic acids in mg/d (IQR): 2480 (1955, 3145) vs. 1897 (1369, 2496); 56 (42,84) vs. 29 (15, 54); 174 (90, 298) vs. 140 (61, 277); and 368 (246, 569) vs. 242 (89, 398), respectively. There was a significant inverse association between dietary flavonoid intake and urine polyphenol excretion; less urinary excretion may imply that some of the polyphenols were eliminated via the gut. Nuts had a significant contribution to the total polyphenols in the diet, suggesting that a single food like walnuts added to habitual diet can increase the polyphenol intake in a Western population.

Dietary approaches to stop hypertension (DASH)-style diet in association with gastroesophageal reflux disease in adolescents

BACKGROUND

Dietary patterns and food items have been associated with gastroesophageal reflux disease (GERD) risk and they have led to conflicting findings. The aim of this study was to determine the association between a dietary approach to stop hypertension (DASH)-style diet with the risk of GERD and its symptoms in adolescents.

STUDY DESIGN

Cross-sectional.

METHODS

This study was performed on 5,141 adolescents aged between 13 and 14 years. Dietary intake was evaluated using a food frequency method. The diagnosis of GERD was done by using a six-item GERD questionnaire that asked about GERD symptoms. A binary logistic regression was used to assess the association between the DASH-style diet score and GERD and its symptoms in crude and multivariable-adjusted models.

RESULTS

Our findings revealed that after adjustment for all confounding variables, the adolescents with the highest adherence to the DASH-style diet had a lower chance of developing GERD [odds ratio (OR) = 0.50; 95%CI 0.33-0.75, P_trend< 0.001)], reflux (OR = 0.42; 95%CI 0.25-0.71, P_trend=0.001), nausea (OR = 0.59; 95% CI:0.32-1.08, P_trend=0.05) and stomach pain (OR = 0.69; 95%CI 0.49-0.98, P _trend=0.03) compared to those with the lowest adherence. Similar results were found for odds of GERD among boys, and the total population (OR = 0.37; 95%CI: 0.18-0.73, P_trend=0.002, OR = 0.51; 95%CI: 0.34-0.77, P _trend<0.0, respectively).

CONCLUSION

The current study revealed that adherence to a DASH-style diet might protect against GERD and its symptoms including, reflux, nausea, and stomach pain in adolescents. Further prospective research is needed to confirm these findings.

Effect of sorghum and barley-containing bread on plasma total polyphenols, antioxidant status and inflammation in healthy subjects

The aim of this study was to investigate the effect of bread incorporated with whole-grain red sorghum and barley flours on biomarkers of oxidative stress and inflammation in humans. In a randomized cross-over study, 20 healthy subjects consumed either control bread made of all-purpose wheat flour only or bread containing 40% whole-grain red sorghum and barley flours (20% each), with a washout period of 1-2 week. The test breads were fed at breakfast after 12 h fast. Blood samples were collected at baseline (fasting) and 2 h after intake of breads. Plasma total polyphenols, total antioxidant capacity (T-AOC), superoxide dismutase (SOD) activity, thiobarbituric acid reactive substances (TBARS) and highly sensitive C-reactive protein were assessed. Compared to fasting values, the 2 h postprandial levels of plasma total polyphenols (P = 0.001), T-AOC (P = 0.031) and SOD activity (P = 0.026) were significantly higher following consumption of sorghum and barley-containing bread (SBB). Moreover, net changes in plasma total polyphenols (P = 0.001), T-AOC (P = 0.047) and SOD activity (P = 0.035) were significantly higher following consumption of SBB. In conclusion, bread containing whole-grain red sorghum and barely flours enhanced plasma total polyphenols and antioxidant status and hence its consumption would modulate biomarkers of cardio-metabolic health.

The Effects of Walnuts and Academic Stress on Mental Health, General Well-Being and the Gut Microbiota in a Sample of University Students: A Randomised Clinical Trial

Poorer mental health is common in undergraduate students due to academic stress. An interplay between stress and diet exists, with stress influencing food choices. Nutritional interventions may be effective in preventing mental health decline due to complex bidirectional interactions between the brain, the gut and the gut microbiota. Previous studies have shown walnut consumption has a positive effect on mental health. Here, using a randomized clinical trial (Australian New Zealand Clinical Trials Registry, #ACTRN12619000972123), we aimed to investigate the effects of academic stress and daily walnut consumption in university students on mental health, biochemical markers of general health, and the gut microbiota. We found academic stress had a negative impact on self-reported mood and mental health status, while daily walnut consumption improved mental health indicators and protected against some of the negative effects of academic stress on metabolic and stress biomarkers. Academic stress was associated with lower gut microbial diversity in females, which was improved by walnut consumption. The effects of academic stress or walnut consumption in male participants could not be established due to small numbers of participants. Thus, walnut consumption may have a protective effect against some of the negative impacts of academic stress, however sex-dependent mechanisms require further study.

Nuts as a Dietary Enrichment with Selected Minerals-Content Assessment Supported by Chemometric Analysis

Nuts used as a snack and meal accompaniment supply plant protein and fatty acids that are beneficial for human health; however, they can also provide minerals. The aim of this study was to determine the content of selected elements that are often deficient in the diet (calcium, potassium, magnesium, selenium, and zinc) in nuts and determine whether they can be used to supplement deficiencies in the diet. In this study, we analyzed 10 types of nuts (n = 120 samples) that are consumed and available for sale in Poland. The content of calcium, magnesium, selenium, and zinc was determined by the atomic absorption spectrometry method, and flame atomic emission spectrometry was used for determination of potassium contents. The highest median calcium content was found in almonds (2825.8 mg/kg), the highest potassium content in pistachio nuts (15,730.5 mg/kg), the highest magnesium and selenium contents in Brazil nuts (10,509.2 mg/kg and 4348.7 μg/kg, respectively), and the highest zinc content in pine nuts (72.4 mg/kg). All the tested nuts are a source of magnesium, eight types of tested nuts are a source of potassium, six nut types are a source of zinc, and four nut types are a source of selenium; however, among the tested nuts, only almonds can be considered a source of calcium. Moreover, we found that selected chemometric methods can be useful in the classification of nuts. The studied nuts are valuable products that can be used to supplement the diet with selected minerals and can therefore be labelled as functional products crucial for disease prevention.

Meat Food Group Intakes and the Risk of Type 2 Diabetes Incidence

Aim

This study aimed to evaluate the association of meats and their substitute food group intakes, including nuts, eggs, and legumes, with type 2 diabetes (T2D).

Methods

For this secondary analysis, we selected eligible adults (n = 6,112) from the Tehran Lipid and Glucose Study participants with a median follow-up of 6.63 years. Expert nutritionists assessed dietary intakes using a valid and reliable semiquantitative food frequency questionnaire. Biochemical and anthropometric variables were assessed at baseline and follow-up examinations. We used multivariable Cox proportional hazard regression models to estimate the new onset of T2D concerning meats and their substitute food groups.

Results

We performed this study on 2,749 men and 3,363 women, aged 41.4 ± 14.2 and 39.1 ± 13.1 years, respectively. The number of participants with incident T2D was 549. After adjusting for confounders, legume [HR: 1, 0.74 (0.58–0.94), 0.69 (0.54–0.90), 0.65 (0.50–0.84), P-trend = 0.01)] was inversely associated with incident T2D. Fish intake [HR: 1, 1.0 (0.79–1.27), 1.17 (0.91–1.50), 1.14 (0.89–1.45), P-trend = 0.01)] was positively associated with incident T2D. In subjects who reported poultry consumption of 36.4–72.8 g/day, a positive association [HR: 1.33 (1.03–1.71)] between poultry intake and T2D risk was observed.

Conclusion

Our findings revealed that a diet rich in legumes significantly reduced the risk of T2D incidence, while a diet high in poultry increased the risk of T2D incidence, probably due to high-temperature cooking methods and environmental contaminants.

Chronic Stress and Oxidative Stress as Common Factors of the Pathogenesis of Depression and Alzheimer's Disease: The Role of Antioxidants in Prevention and Treatment

There is a growing body of scientific research showing the link between depression and dementia in Alzheimer’s disease (AD). The chronic stress contributes to the formation of oxidative stress in the parts of the brain involved in the development of depression and AD. The scientific literature reports the significant role of antioxidants, which are highly effective in treating these diseases. In this review, we have summarized the relationship between chronic stress, oxidative stress, and the changes in the brain they cause occurring in the brain. Among all the compounds showing antioxidant properties, the most promising results in AD treatment were observed for Vitamin E, coenzyme Q10 (CoQ10), melatonin, polyphenols, curcumin, and selenium. In case of depression treatment, the greatest potential was observed in curcumin, zinc, selenium, vitamin E, and saffron.

Acute consumption of pecans decreases angiopoietin-like protein-3 in healthy males: a secondary analysis of randomized controlled trials

Angiopoietin-like proteins (ANGPTL)-3 and -4 regulate lipid metabolism, but the effect of tree nuts of varying fatty acid composition on post-meal responses is unknown. The purpose of the study was to conduct a secondary analysis of two studies on ANGPTL3 and -4 responses to meals containing different tree nuts. We hypothesized that the pecan-containing meal would mitigate postprandial rises in ANGPTL3 compared to the traditional meal without nuts in males, but not females. In addition, we hypothesized that there would be no other differences between any other treatments in ANGPTL3 or -4 responses. The two studies were double-blind, randomized crossover trials. Twenty-two adults (10=male, 12=female) completed study 1, which compared meals containing pecans vs. no nuts (control), and thirty adults (14=male, 16=female) completed study 2, which compared meals containing black walnuts, English walnuts (EW), or no nuts (control). Blood was collected at fasting, 30, 60, 120, and 180min postprandially. In study 1, ANGPTL3 was suppressed more in pecan vs. control in males (iAUC: -579.4±219.4 vs. -128.4±87.1pg/mL/3h, P<.05). In study 2, there was no difference in ANGPTL3 between black walnuts vs. EW, but ANGPTL3 was suppressed more in control vs. black walnuts in females only (iAUC: -196.4±138.4 vs. 102.1±90.1pg/mL/3h, P<.05). There were no differences in ANGPTL4 between treatments. In conclusion, adding pecans to a meal decreased ANGPTL3 in males, but not females. These data highlight the importance of investigating the impact of nutrients and sex on postprandial ANGPTL3 ad -4 responses to better understand their ability to reduce cardiovascular disease risk.

Health Benefits Related to Tree Nut Consumption and Their Bioactive Compounds

Long-term studies with regular tree nut consumption have indicated positive outcomes for multiple health benefits. Here, we review the beneficial effects of tree nuts, highlighting the impact on glucose modulation, body weight management, cardiovascular risk, inflammation, oxidative stress, cognitive performance, and gut microbiota. Nuts are important sources of nutrients and phytochemicals, which, together with a healthy lipid profile, could help prevent certain chronic diseases, protect against oxidative stress and inflammation, and improve cognitive performance, thus reducing the impact of aging and neurodegeneration.

Effect of Food Processing on Antioxidant Potential, Availability, and Bioavailability

Antioxidants are understood to play a key role in disease prevention; because of this, research and interest in these compounds are ever increasing. Antioxidative phytochemicals from natural sources are preferred, as some negative implications have been associated with synthetic antioxidants. Beans, nuts, seeds, fruits, and vegetables, to name a few, are important sources of phytochemicals, which have purported health benefits. The aforementioned plant sources are reportedly rich in bioactive compounds, most of which undergo some form of processing (boiling, steaming, soaking) prior to consumption. This article briefly reviews selected plants (beans, nuts, seeds, fruits, and vegetables) and the effects of processing on the antioxidant potential, availability, and bioavailability of phytochemicals, with research from our laboratory and other studies determining the health benefits of and processing effects on bioactive compounds.

Effects of baru almond oil (Dipteryx alata Vog.) supplementation on body composition, inflammation, oxidative stress, lipid profile, and plasma fatty acids of hemodialysis patients: A randomized, double-blind, placebo-controlled clinical trial

BACKGROUND

The consumption of nuts and edible seeds is associated with the improvement of the metabolic profile and reduction of cardiovascular diseases. However, the effects of its subproducts, such as oil, are still poorly studied. This study aimed to evaluate the effect of the baru almond oil supplementation on inflammation, oxidative stress, body composition, lipid profile, and plasma fatty acids of hemodialysis patients.

METHODS

In a randomized, double-blind, 12-week placebo-controlled clinical study, hemodialysis patients were supplemented with 5 g of baru oil (BG, n = 17) or 5 g of mineral oil (placebo, BP, n = 12). Body composition, renal function, ultra-sensitive C-reactive protein (us-CRP), oxidative stress, plasma fatty acids, and lipid profile were analysed before and after the intervention.

RESULTS

Patients were aged 50.5 ± 2.2 years and the average time of dialyses was 52,1 ± 42,6 months. The BG decreased us-CRP concentration compared to PG (-1.2 ± 0.2 vs. + 0.8 ± 0.2 mg / L,d = 0.88; p =  0.01). Baru almond oil supplementation was not effective in improving body composition, lipid profile, and oxidative stress.

CONCLUSION

Baru almond oil supplementation decreased us-CRP concentration in patients with chronic kidney disease under hemodialysis treatment.

RETRACTED: Nut consumption with risk of hypertension and type 2 diabetes mellitus: A meta-analysis of prospective cohort studies

BACKGROUND

The consumption of nuts was reported to be associated with risk of hypertension and type 2 diabetes mellitus (T2DM), but the results were inconclusive. The aim of this study was to systematically examine longitudinal studies investigating nut intake in relation to risk of hypertension and T2DM.

METHODS

A systematic search of the PubMed and EMBASE databases to 31 March 2013 was performed. Reference lists of retrieved articles were also screened. Summary relative risks (SRRs) and 95% confidence intervals (CIs) were calculated using a random-effects model. Q and I2 statistics were used to examine between-study heterogeneity.

RESULTS

A total of nine prospective cohort studies (three for hypertension and six for T2DM) were identified. Using random effects models, we found that based on the highest vs lowest analysis, nut consumption were inversely associated with risk of hypertension (SRR = 0.84, 95% CI: 0.76-0.93, pheterogeneity = 0.831, I2 = 0%). Dose-response analyses indicated that nut consumption at more than two servings/wk, but not ne serving/wk, had a preventative role in the hypertension. In addition, nut consumption was not associated with risk of T2DM (SRRs = 0.98, 95% CI: 0.84-1.15; pheterogeneity = 0.008, I2 = 67.7%) on the basis of the highest vs lowest analysis. This null association was also shown in the dose-response analysis.

CONCLUSION

In our meta-analysis, nut consumption is found to be inversely associated with hypertension risk but is not associated with the risk of T2DM.

Enzyme-mediated one-pot synthesis of hydrogel with the polyphenol cross-linker for skin regeneration

Polyphenols can trigger immunity that activates intracellular anti-inflammatory signaling and prevents external infections. In this study, we report the fabrication of chitosan-based hydrogels with epigallocatechin gallate (EGCG) using enzyme-mediated one-pot synthesis. The tyrosinase-mediated oxidative reaction of the phenolic rings of EGCG with the primary amines on chitosan results in stable EGCG-chitosan hydrogels. The EGCG concentrations contributed to the cross-linking density and physical properties of EGCG-chitosan hydrogels. Furthermore, EGCG-chitosan hydrogels maintained intrinsic properties such as antibacterial and antioxidant effects. When endotoxin-activated RAW 264.7 macrophage cells were cultured with EGCG-chitosan hydrogels, the hydrogels reduced the inflammatory response of the RAW 264.7 cells. Furthermore, subcutaneous implantation of EGCG-chitosan hydrogels reduced endogenous macrophage and monocyte activation. When the EGCG-chitosan hydrogels were applied to a full-skin defect wound, they facilitated skin regeneration. Our study demonstrates that the one-pot synthesized EGCG-chitosan hydrogels can be applied in broad tissue regeneration applications that require immune modulation.

Finger millet porridges subjected to different processing conditions showed low glycemic index and variable efficacy on plasma antioxidant capacity of healthy adults

Abstract

Finger millet porridges (FMP), rich in nutrient and non-nutrient compounds have been used in the traditional food cultures in Asia. The aims of the study were to determine the effect of different processing conditions of finger millet grains on glycemic response, phenolic content and the antioxidant activities of FMP and to determine the short term and long term efficacy of its consumption on plasma antioxidant levels of healthy adults. Twelve types of FMP were prepared combining different processing conditions. Phenolic content of porridges as well as antioxidant activities were determined. The glycemic index (GI) and glycemic load (GL) values of FMP were also evaluated. The long term efficacy of FMP consumption on plasma glucose (PG), total cholesterol (TC) levels and plasma antioxidant capacity (PAC) of 18 subjects were investigated using a 24 weeks randomized cross-over study. The short term efficacy of porridge consumption on AC was determined. PAC was measured by trolox equivalent antioxidant capacity (TEAC) and ferric ion reducing antioxidant power (FRAP). All FMP exhibited low GI values (< 55) except the raw roasted flour which showed high and medium GI values for both particle sizes used. Parboiling of finger millet grains with 15 min steaming produced FMP with low glycemic response and possessed high PAC. Compared to baseline, PAC measured using FRAP and TEAC assays increased after 8 weeks consumption of porridge though significant changes were not observed for PG and TC levels. Furthermore, PAC was increased by 23 and 14% after 2 h of porridge consumption as measured by TEAC and FRAP, respectively. FMP consumption increased the plasma total antioxidant capacity of healthy adults. Further research on examining the potential of FMP on improving the antioxidant capacity in patients with diabetes is warranted.

Graphical abstract

Beneficial Effects of Walnuts on Cognition and Brain Health

Oxidative stress and neuroinflammation have important roles in the aging process, mild cognitive impairment (MCI), Alzheimer’s disease (AD), and other brain disorders. Amyloid beta protein (Aβ) is the main component of amyloid plaques in the brains of people with AD. Several studies suggest that Aβ increases the generation of free radicals in neurons, which leads to oxidative damage and cell death. Aβ can also induce neuroinflammation by increasing pro-inflammatory cytokines and enzymes. Walnuts contain several components that have antioxidant and anti-inflammatory effects. Animal and human studies from our and other groups suggest that supplementation with walnuts in the diet may improve cognition and reduce the risk and/or progression of MCI and AD. In the transgenic AD mouse model (AD-tg), we have reported the beneficial effects of a diet with walnuts on memory, learning, motor coordination, anxiety, and locomotor activity. Human clinical trials have also suggested an association of walnut consumption with better cognitive performance and improvement in memory when compared to baseline in adults. Our recent study in AD-tg mice has shown that a walnut-enriched diet significantly improves antioxidant defense and decreases free radicals’ levels, lipid peroxidation, and protein oxidation when compared to a control diet without walnuts. These findings suggest that a diet with walnuts can reduce oxidative stress by decreasing the generation of free radicals and by boosting antioxidant defense, thus resulting in decreased oxidative damage to lipids and proteins. An in vitro study with synthetic Aβ showed that walnut extract can inhibit Aβ fibrillization and solubilize the preformed Aβ fibrils, suggesting an anti-amyloidogenic property of walnuts. Because it takes many years for cognitive impairment and dementia to develop, we suggest that early and long-term dietary supplementation with walnuts may help to maintain cognitive functions and may reduce the risk of developing, or delay the onset and/or slow the progression of, MCI and dementia by decreasing Aβ fibrillization, reducing oxidative damage, increasing antioxidant defense, and decreasing neuroinflammation. Furthermore, several animal and human studies have suggested that walnuts may also decrease the risk or progression of other brain disorders such as Parkinson’s disease, stroke, and depression, as well as of cardiovascular disease and type 2 diabetes. Together, these reports suggest the benefits of a walnut-enriched diet in brain disorders and in other chronic diseases, due to the additive or synergistic effects of walnut components for protection against oxidative stress and inflammation in these diseases.

A Prospective Study of Serum Vitamin E and 28-Year Risk of Lung Cancer

BACKGROUND

Epidemiologic data are inconsistent regarding the vitamin E-lung cancer association, and no study to our knowledge has examined serologic changes in vitamin E status in relation to subsequent risk.

METHODS

In a cohort of 22 781 male smokers in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study, we ascertained 3184 lung cancer cases during up to 28 years of observation. Cox proportional hazards models examined whether higher serum alpha-tocopherol concentrations at baseline, 3 years, or the interval change were associated with lower lung cancer risk. All statistical tests were two-sided.

RESULTS

After adjustment for age, body mass index, smoking intensity and duration, serum total cholesterol, and trial intervention group, we found lower lung cancer risk in men with high baseline alpha-tocopherol (fifth quintile [Q5] vs Q1, hazard ratio [HR] = 0.76, 95% confidence interval [CI] = 0.66 to 0.87, Ptrend < .001). A similar reduction in risk was seen for serum alpha-tocopherol at 3 years (Q5 vs Q1, HR = 0.78, 95% CI = 0.67 to 0.91, Ptrend = .004). The inverse risk association appeared stronger for younger men and those who had smoked fewer years but was similar across trial intervention groups. We also found reduced risk among men not supplemented with vitamin E who had a lower serum alpha-tocopherol at baseline and greater increases in concentrations at 3 years (third tertile vs first tertile of serum alpha-tocopherol change, HR = 0.74, 95% CI = 0.59 to 0.91, P = .005).

CONCLUSIONS

Higher vitamin E status, as measured by serum alpha-tocopherol concentration, as well as repletion of a low vitamin E state, was related to decreased lung cancer risk during a 28-year period. Our findings provide evidence supporting the importance of adequate physiological vitamin E status for lung cancer risk reduction.

Relationship Between Serum Alpha-Tocopherol and Overall and Cause-Specific Mortality

RATIONALE

Although there has been a long-standing interest in the human health effects of vitamin E, a comprehensive analysis of the association between circulating vitamin E and long-term mortality has not been conducted.

OBJECTIVE

Determine whether serum α-tocopherol (the predominant form of vitamin E) is related to long-term overall and cause-specific mortality and elucidate the dose-response relationships with better quantification of the associations.

METHODS AND RESULTS

We conducted a biochemical analysis of 29 092 participants in the ATBC Study (Alpha-Tocopherol, Beta-Carotene Cancer Prevention) that originally tested vitamin E and β-carotene supplementation. Serum α-tocopherol was measured at baseline using high-performance liquid chromatography, and during a 30-year follow-up we identified 23 787 deaths, including deaths from cardiovascular disease (9867), cancer (7687), respiratory disease (2161), diabetes mellitus (119), injuries and accidents (1255), and other causes (2698). After adjusting for major risk factors, we found that men with higher serum α-tocopherol had significantly lower all-cause mortality (hazard ratios=0.83, 0.79, 0.75, and 0.78 for quintile 2 (Q2)-Q5 versus Q1, respectively; P_trend<0.0001), and significantly decreased mortality from cardiovascular disease, heart disease, stroke, cancer, respiratory disease, and other causes, with risk reductions from 17% to 47% for the highest versus lowest quintile. The α-tocopherol association with overall mortality was similar across subgroups of smoking intensity, years of smoking, alcohol consumption, trial supplementation, and duration of follow-up. The association was, however, significantly modified by baseline age and body mass index, with stronger inverse associations for younger men and men with a lower body mass index ( P_interaction≤0.006).

CONCLUSIONS

In this long-term prospective cohort study, higher baseline serum α-tocopherol biochemical status was associated with lower risk of overall mortality and mortality from all major causes. Our data support the long-term health benefits of higher serum α-tocopherol for overall and chronic disease mortality and should be replicated in other more diverse populations.

Non-Targeted HPLC-UV Fingerprinting as Chemical Descriptors for the Classification and Authentication of Nuts by Multivariate Chemometric Methods

Recently, the authenticity of food products has become a great social concern. Considering the complexity of the food chain and that many players are involved between production and consumption; food adulteration practices are rising as it is easy to conduct fraud without being detected. This is the case for nut fruit processed products, such as almond flours, that can be adulterated with cheaper nuts (hazelnuts or peanuts), giving rise to not only economic fraud but also important effects on human health. Non-targeted HPLC-UV chromatographic fingerprints were evaluated as chemical descriptors to achieve nut sample characterization and classification using multivariate chemometric methods. Nut samples were extracted by sonication and centrifugation, and defatted with hexane; extracting procedure and conditions were optimized to maximize the generation of enough discriminant features. The obtained HPLC-UV chromatographic fingerprints were then analyzed by means of principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) to carry out the classification of nut samples. The proposed methodology allowed the classification of samples not only according to the type of nut but also based on the nut thermal treatment employed (natural, fried or toasted products).

Adherence to a healthy dietary pattern is associated with less severe depressive symptoms among adolescent girls

There is growing interest on the impact of diet on depressive disorders. However, there are limited data on the association between dietary patterns and depression symptoms among Iranian adolescents. The aim of this study was to evaluate the association between dietary patterns and depression score among Iranian adolescent girls. Data were obtained from 750 adolescent girls, who were recruited from several schools using a random cluster sampling. Dietary data were collected using a valid and reliable food frequency questionnaire (FFQ). Beck's depression inventory (BDI-II) was used to assess depression severity score. The prevalence of girls diagnosed with depression was 29.1%. Three major dietary patterns were identified in the study based on factor analysis: "Healthy", "Traditional" and "Western". The multivariate-adjusted odds ratio of having depressive symptoms was 0.55 (95% confidence intervals, 0.34-0.89) for the highest versus lowest quartile of the healthy dietary pattern score. However, there were no significant associations between the Traditional and Western dietary patterns and depression symptoms. Our results indicate that adherence to a Healthy dietary pattern characterized by high intakes of fruits, vegetables, fish and dairy products is associated with a lower probability of having depressive symptoms among Iranian adolescent girls.

Assessment of Antioxidant Capacity and Putative Healthy Effects of Natural Plant Products Using Soybean Lipoxygenase-Based Methods. An Overview

In the last decades, increasing demand of antioxidant-rich foods and growing interest in their putative role in prevention of degenerative diseases have promoted development of methods for measuring Antioxidant Capacity (AC). Nevertheless, most of these assays use radicals and experimental conditions far from the physiological ones, and are able to estimate only one or a few antioxidant mechanisms. On the other hand, the novel LOX/RNO and LOX⁻FL methods, based on secondary reactions between the soybean lipoxygenase (LOX)-1 isoenzyme and either 4-nitroso-N,N-dimethylaniline (RNO) or fluorescein (FL), may provide a more comprehensive AC evaluation. In fact, they are able to detect simultaneously many antioxidant functions (scavenging of some physiological radical species, iron ion reducing and chelating activities, inhibition of the pro-oxidant apoenzyme) and to highlight synergism among phytochemicals. They are applied to dissect antioxidant properties of several natural plant products: food-grade antioxidants, cereal and pseudocereal grains, grain-derived products, fruits. Recently, LOX⁻FL has been used for ex vivo AC measurements of human blood samples after short- and long-term intakes of some of these foods, and the effectiveness in improving serum antioxidant status was evaluated using the novel Antioxidant/Oxidant Balance (AOB) parameter, calculated as an AC/Peroxide Level ratio. An overview of data is presented.

Intestinal Absorption and Antioxidant Activity of Grape Pomace Polyphenols

The absorption and antioxidant activity of polyphenols from grape pomace (GP) are important aspects of its valorization as a feed additive in the diet of weaned piglets. This study aimed to evaluate the presence of polyphenols from GP both in vitro in IPEC cells and in vivo in the duodenum and colon of piglets fed with diets containing or not 5% GP and also to compare and correlate the aspects of their in vitro and in vivo absorption. Total polyphenolic content (TPC) and antioxidant status (TAS, CAT, SOD and GPx enzyme activity, and lipid peroxidation-TBARS level) were assessed in duodenum and colon of piglets fed or not a diet with 5% GP. The results of UV-Vis spectroscopy demonstrated that in cellular and extracellular medium the GP polyphenols were oxidized (between λmax = 276 nm and λmax = 627.0 nm) with the formation of o-quinones and dimers. LC-MS analysis indicated a procyanidin trimer possibly C2, and a procyanidin dimer as the major polyphenols identified in GP, 12.8% of the procyanidin trimer and 23% of the procyanidin dimer respectively being also found in the compound feed. Procyanidin trimer C2 is the compound accumulated in duodenum, 73% of it being found in the colon of control piglets, and 62.5% in the colon of GP piglets. Correlations exist between the in vitro and in vivo investigations regarding the qualitative evaluation of GP polyphenols in the cells (λmax at 287.1 nm) and in the gut (λmax at 287.5 nm), as oxidated metabolic products. Beside the presence of polyphenols metabolites this study shows also the presence of the unmetabolized procyanidin trimers in duodenum and colon tissue, an important point in evaluating the benefic actions of these molecules at intestinal level. Moreover the in vivo study shows that a 5% GP in piglet’s diet increased the total antioxidant status (TAS) and decreased lipid peroxidantion (TBARS) in both duodenum and colon, and increased SOD activity in duodenum and CAT and GPx activity in colon. These parameters are modulated by the different polyphenols absorbed, mainly by the procyanidin trimers and catechin on one side and the polyphenols metabolites on the other side.

Nut consumption and total and cause-specific mortality: results from the Golestan Cohort Study

Background

A number of prospective studies have observed inverse associations between nut consumption and chronic diseases. However, these studies have predominantly been conducted in Western countries, where nut consumption tends to be more common among individuals with healthier lifestyles. It is important to examine the association in other parts of the world, and particularly among populations with different patterns of disease, socioeconomic status, lifestyles and disease risk factors. Our objective was to examine the association between nut consumption and mortality in a population whose nut consumption does not track with a healthy lifestyle.

Methods

We examined the association between nut consumption and all-cause and cause-specific mortality in the 50 045 participants of the Golestan Cohort Study. Participants were aged 40 and older at baseline in 2004, and have been actively followed since that time. Dietary data were collected using a validated semi-quantitative food frequency questionnaire that was administered at baseline.

Results

During 349 677 person-years of follow-up, 3981 cohort participants died, including 1732 women and 2249 men. Nut consumption was associated inversely with all-cause mortality. The pooled multivariate adjusted hazard ratios for death among participants who ate nuts, as compared with those who did not, were 0.89 [95% confidence interval (CI), 0.82-0.95] for the consumption of less than one serving of nuts per week, 0.75 (95% CI, 0.67-0.85) for one to less than three servings per week and 0.71 (95% CI, 0.58-0.86) for three or more servings per week ( P < 0.001 for trend). Among specific causes, significant inverse associations were observed between nut consumption and deaths due to cardiovascular disease, all cancers and gastrointestinal cancers.

Conclusions

This study provides evidence for an inverse association between nut consumption and mortality in a developing country, where nut consumption does not track with a healthy lifestyle. Further work is needed to establish the underlying mechanisms responsible for this association.

Dietary Supplementation of Almond Prevents Oxidative Stress by Advocating Antioxidants and Attenuates Impaired Aversive Memory in Male Rats

Scopolamine, an anti-muscarinic agent, has been shown to induce amnesia and oxidative stress similar to that observed in the older age. The present study was designed to determine the relationship between the oxidative status and memory improvement in scopolamine injected rats pre-administered with almonds. Rats (n = 8) in the almond group were administered orally with 400 mg/kg almond suspension for 28 days daily before the intraperitoneal injection of scopolamine (0.5 mg/kg). Passive avoidance task (PAT) was used to assess memory function at the end of treatment. The present study revealed that scopolamine injection significantly impaired the memory function in rats pre-treated with saline which was accompanied by increased oxidative stress as evident by increased brain malondialdehyde (MDA) levels and reduced activities of antioxidant enzymes as compared to healthy controls. Pre-treatment with almond significantly ameliorated scopolamine-induced oxidative stress and memory dysfunction. These findings suggest that dietary supplementation with almonds may have a beneficial effect in reducing the risk of oxidative stress-induced memory loss and delaying or preventing the onset of age-related memory impairment.

Nut Consumption and Survival in Patients With Stage III Colon Cancer: Results From CALGB 89803 (Alliance)

Purpose

Observational studies have reported increased colon cancer recurrence and mortality in patients with states of hyperinsulinemia, including type 2 diabetes, obesity, sedentary lifestyle, and high glycemic load diet. Nut intake has been associated with a lower risk of type 2 diabetes, metabolic syndrome, and insulin resistance. However, the effect of nut intake on colon cancer recurrence and survival is not known.

Patients and Methods

We conducted a prospective, observational study of 826 eligible patients with stage III colon cancer who reported dietary intake on food frequency questionnaires while enrolled onto a randomized adjuvant chemotherapy trial. Using Cox proportional hazards regression, we assessed associations of nut intake with cancer recurrence and mortality.

Results

After a median follow-up of 6.5 years, compared with patients who abstained from nuts, individuals who consumed two or more servings of nuts per week experienced an adjusted hazard ratio (HR) for disease-free survival of 0.58 (95% CI, 0.37 to 0.92; P_trend = .03) and an HR for overall survival of 0.43 (95% CI, 0.25 to 0.74; P_trend = .01). In subgroup analysis, the apparent benefit was confined to tree nut intake (HR for disease-free survival, 0.54; 95% CI, 0.34 to 0.85; P_trend = .04; and HR for overall survival, 0.47; 95% CI, 0.27 to 0.82; P_trend = .04). The association of total nut intake with improved outcomes was maintained across other known or suspected risk factors for cancer recurrence and mortality.

Conclusion

Diets with a higher consumption of nuts may be associated with a significantly reduced incidence of cancer recurrence and death in patients with stage III colon cancer.

Effects of dietary almond- and olive oil-based docosahexaenoic acid- and vitamin E-enriched beverage supplementation on athletic performance and oxidative stress markers

Functional beverages based on almonds and olive oil and enriched with α-tocopherol and docosahexaenoic acid (DHA) could be useful in modulating oxidative stress and enhancing physical performance in sportsmen. The aim of this work was to evaluate the effects of supplementation with functional beverages on physical performance, plasma and erythrocyte fatty acids' and polyphenol handling, oxidative and nitrative damage, and antioxidant and mitochondrial gene expression in young and senior athletes. Athletes performed maximal exercise tests before and after one month of dietary supplementation and blood samples were taken immediately before and one hour after each test. The beverages did not alter performance parameters during maximal exercise. Supplementation increased polyunsaturated and reduced saturated plasma fatty acids while increasing the DHA erythrocyte content; it maintained basal plasma and blood polyphenol levels, but increased the blood cell polyphenol concentration in senior athletes. Supplementation protects against oxidative damage although it enhances nitrative damage in young athletes. The beverages enhance the gene expression of antioxidant enzymes in peripheral blood mononuclear cells after exercise in young athletes.

Anti-aging potential of tree nuts with a focus on the phytochemical composition, molecular mechanisms and thermal stability of major bioactive compounds

Tree nuts, complete functional foods, contain macro- and micronutrients of high biological value.

Nuts and Human Health Outcomes: A Systematic Review

There has been increasing interest in nuts and their outcome regarding human health. The consumption of nuts is frequently associated with reduction in risk factors for chronic diseases. Although nuts are high calorie foods, several studies have reported beneficial effects after nut consumption, due to fatty acid profiles, vegetable proteins, fibers, vitamins, minerals, carotenoids, and phytosterols with potential antioxidant action. However, the current findings about the benefits of nut consumption on human health have not yet been clearly discussed. This review highlights the effects of nut consumption on the context of human health.

Walnut extract modulates activation of microglia through alteration in intracellular calcium concentration

Diets supplemented with walnuts have shown to protect brain against oxidative and inflammatory cytotoxicity and promote protective cellular and cognitive function. The current study was undertaken to test the hypothesize that whole walnut extract (WNE) inhibits lipopolysaccharide (LPS)-induced microglial activation by regulating calmodulin (CaM) expression through [Ca²⁺]_i. To test this hypothesis, we used an in vitro model the highly aggressively proliferating immortalized cells, a rat microglial cell line, treated with various concentrations of WNEs. Treatment with WNE (1.5%, 3%, or 6%) induced a slow rise in intracellular calcium in a concentration- and time-dependent manner, and this rise became exaggerated when cells were depolarized with potassium chloride (100 mmol/L). Cells treated with WNE (1%, 3%, or 6%) upregulated CaM protein levels, with 1 hour posttreatment being the peak time, regardless of WNE concentration. Interestingly, this WNE-induced upregulation of CaM was blocked by pretreatment with thapsigargin. Additionally, treatment with WNE (1%, 3%, or 6%) 1 hour prior to LPS treatment was found to be effective in preventing LPS-induced upregulation of inducible nitric oxide synthase expression, upregulation of ionized Ca²⁺-binding adaptor-1, and downregulation of CaM. These findings suggest that bioactive compounds in walnut are capable of modulating microglial activation through regulation of intracellular calcium and CaM expression. Nutritional interventions using walnuts may be effective in the amelioration of chronic inflammation and neurodegeneration.

Different effectiveness of two pastas supplemented with either lipophilic or hydrophilic/phenolic antioxidants in affecting serum as evaluated by the novel Antioxidant/Oxidant Balance approach

Effectiveness in improving serum antioxidant status of two functional pastas was evaluated by the novel Antioxidant/Oxidant Balance (AOB) parameter, calculated as Antioxidant Capacity (AC)/Peroxide Level ratio, assessed here for the first time. In particular, Bran Oleoresin (BO) and Bran Water (BW) pastas, enriched respectively with either lipophilic (tocochromanols, carotenoids) or hydrophilic/phenolic antioxidants extracted from durum wheat bran, were studied. Notably, BO pasta was able to improve significantly (+65%) serum AOB during four hours after intake similarly to Lisosan G, a wheat antioxidant-rich dietary supplement. Contrarily, BW pasta had oxidative effect on serum so as conventional pasta and glucose, thus suggesting greater effectiveness of lipophilic than hydrophilic/phenolic antioxidants under our experimental conditions. Interestingly, no clear differences between the two pastas were observed, when AC measurements of either serum after pasta intake or pasta extracts by in vitro assays were considered, thus strengthening effectiveness and reliability of AOB approach.

Nut consumption and risk of colorectal cancer in women

BACKGROUND/OBJECTIVES

Increasing nut consumption has been associated with reduced risk of obesity and type II diabetes, the risk factors for colorectal cancer. However, the association between nut consumption and colorectal cancer risk is unclear. We aimed to examine the association of long-term nut consumption with risk of colorectal cancer.

SUBJECTS/METHODS

We prospectively followed 75,680 women who were free of cancer at baseline in the Nurses' Health Study, and examined the association between nut consumption and colorectal cancer risk. Nut consumption was assessed at baseline and updated every 2-4 years. Relative risks (RRs) and 95% confidence intervals (95% CIs) were estimated using Cox proportional hazards models.

RESULTS

During 2,103,037 person-years of follow-up, we identified 1503 colorectal cancer cases. After adjustment for other known or suspected risk factors, women who consumed nuts 2 or more times per week (that is, ⩾ 56 g per week) had a 13% lower risk of colorectal cancer compared with those who rarely consumed nuts, but the association was not statistically significant (RR: 0.87; 95% CI: 0.72-1.05; P-trend: 0.06). No association was observed for peanut butter.

CONCLUSIONS

In this large prospective cohort of women, frequent nut consumption was not significantly associated with colorectal cancer risk after adjusting for other risk factors.

Oligonol, a low-molecular-weight polyphenol derived from lychee fruit, protects the pancreas from apoptosis and proliferation via oxidative stress in streptozotocin-induced diabetic rats

We have identified the pancreato-protective effects of Lychee Fruit-Derived Polyphenol Mixture, Oligonol, on diabetes.

New insights into seaweed polyphenols on glucose homeostasis

CONTEXT

Polyphenol-rich marine macroalgae are gaining dietary importance due to their influence over diabetes mellitus and the role as a vital source of high-value nutraceuticals. Their assorted beneficial effects on human health include competitive inhibition of digestive enzymes, varying the activity of hepatic glucose-metabolizing enzymes, lowering the plasma glucose levels, and lipid peroxidation, delaying the aging process.

OBJECTIVE

In this paper, we review the health beneficial effects of polyphenols and phlorotannins from brown seaweeds with special emphasis on their inhibitory effects on carbohydrate-metabolizing enzymes.

METHODS

A survey of literature from databases such as Sciencedirect, Scopus, Pubmed, Springerlink, and Google Scholar from the year 1973 to 2013 was done to bring together the information relating to drug discovery from brown seaweeds as a source for diabetes treatment.

RESULTS

Over the past two decades, 20 different bioactive polyphenols/phlorotannins have been isolated and studied from 10 different brown algae. Discussion of the positive effect on the inhibition of enzymes metabolizing carbohydrates in both in vitro and in vivo experiments are included.

CONCLUSION

Despite the recent advancements in isolating bioactive compounds from seaweeds with potential health benefit or pharmaceutical behavior, studies on the polyphenol effectiveness on glucose homeostasis in human beings are very few in response to their functional characterization. Added research in this area is required to confirm the close connection of polyphenol rich seaweed-based diet consumption with glucose homeostasis and the exciting possibility of prescribing polyphenols to treat the diabetes pandemic.

Fat intake after prostate cancer diagnosis and mortality in the Physicians' Health Study

PURPOSE

Diet after prostate cancer diagnosis may impact disease progression. We hypothesized that consuming saturated fat after prostate cancer diagnosis would increase risk of mortality, and consuming vegetable fat after diagnosis would lower the risk of mortality.

METHODS

This was a prospective study among 926 men with non-metastatic prostate cancer in the Physicians' Health Study who completed a food frequency questionnaire a median of 5 years after diagnosis and were followed for a median of 10 years after the questionnaire. We examined post-diagnostic saturated, monounsaturated, polyunsaturated, and trans fat, as well as animal and vegetable fat, intake in relation to all-cause and prostate cancer-specific mortality. Hazard ratios (HR) and 95 % confidence intervals (CI) were estimated using multivariate Cox proportional hazards regression.

RESULTS

We observed 333 deaths (56 prostate cancer deaths) during follow-up. Men who obtained 5 % more of their daily calories from saturated fat and 5 % less of their daily calories from carbohydrate after diagnosis had a 1.8-fold increased risk of all-cause mortality (HR 1.81; 95 % CI 1.20, 2.74; p value 0.005) and a 2.8-fold increased risk of prostate cancer-specific mortality (HR 2.78; 95 % CI 1.01, 7.64; p value 0.05). Men who obtained 10 % more of their daily calories from vegetable fats and 10 % less of their daily calories from carbohydrates had a 33 % lower risk of all-cause mortality (HR 0.67; 95 % CI 0.47, 0.96; p value 0.03).

CONCLUSIONS

Among men with non-metastatic prostate cancer, saturated fat intake may increase risk of death and vegetable fat intake may lower risk of death.

Tree Nut consumption is associated with better adiposity measures and cardiovascular and metabolic syndrome health risk factors in U.S. Adults: NHANES 2005-2010

INTRODUCTION

Previous research has shown inconsistencies in the association of tree nut consumption with risk factors for cardiovascular disease (CVD) and metabolic syndrome (MetS).

OBJECTIVE

To determine the association of tree nut consumption with risk factors for CVD and for MetS in adults.

METHODS

NHANES 2005-2010 data were used to examine the associations of tree nut consumption with health risks in adults 19+ years (n = 14,386; 51% males). Tree nuts were: almonds, Brazil nuts, cashews, filberts [hazelnuts], macadamias, pecans, pine nuts, pistachios, and walnuts. Group definitions were non-consumers < ¼ ounce/day and consumers of ≥ ¼ ounce/day tree nuts using data from 24-h dietary recalls. Means and ANOVA (covariate adjusted) were determined using appropriate sample weights. Using logistic regression, odds ratios of being overweight (OW)/obese (OB) (body mass index [BMI] >25/<30 and ≥30, respectively) and having CVRF or MetS, were determined.

RESULTS

Tree nut consumption was associated with lower BMI (p = 0.004), waist circumference (WC) (p = 0.008), systolic blood pressure (BP) (p = 0.001), Homeostatic Model Assessment-Insulin Resistance (p = 0.043), and higher high density lipoprotein-cholesterol (p = 0.022), compared with no consumption, and a lower likelihood of OB (-25%), OW/OB (-23%), and elevated WC (-21%).

CONCLUSIONS

Tree nut consumption was associated with better weight status and some CVRF and MetS components.

Meta-analysis of prospective studies on the effects of nut consumption on hypertension and type 2 diabetes mellitus

BACKGROUND

Inconclusive reports have been published on the consumption of nuts and the risk of hypertension and type 2 diabetes mellitus (T2DM). We performed a meta-analysis of prospective studies to assess the effects of nut consumption on hypertension and T2DM risks.

METHODS

A PUBMED and EMBASE database search was performed. Summary relative risks (SRRs) and 95% confidence intervals (CIs) were calculated using a random-effects model. Q and I2 statistics were used to examine between-study heterogeneity.

RESULTS

A total of eight articles with nine prospective cohort studies (three hypertension studies and six T2DM studies) were selected. Using random effects models, we found that compared with never/rare consumers of nuts, those consuming >2 servings per week had an 8% lower risk of hypertension (SRR = 0.92, 95% CI: 0.87-0.97, P(heterogeneity)  = 0.590, I2  = 0%), while consumption of nuts at one serving per week had similar risk (SRR = 0.97, 95% CI: 0.83-1.13). In addition, nuts consumption was not associated with risk of T2DM (SRRs = 0.98, 95% CI: 0.84-1.15; P(heterogeneity)  = 0.008, I2  = 67.7%) on the basis of the highest versus lowest analysis. This null association was also shown in the dose-response analysis.

CONCLUSION

Findings from this meta-analysis indicate that consumption of nuts (>2 servings/week) may be inversely associated with hypertension risk, but not with T2DM risk.

Nut consumption and risk of mortality in the Physicians' Health Study

BACKGROUND

Previous studies have suggested that nut consumption is associated with beneficial cardiovascular outcomes. However, limited data are available on the association between nut intake and all-cause mortality.

OBJECTIVE

Our aim was to test the hypothesis that nut consumption is inversely associated with the risk of all-cause mortality.

DESIGN

In this prospective cohort study in 20,742 male physicians, we assessed nut intake between 1999 and 2002 via a food-frequency questionnaire and ascertained deaths through an endpoint committee. We used Cox regression to estimate multivariable-adjusted HRs for death according to nut consumption. In secondary analyses, we evaluated associations of nut consumption with cause-specific mortality.

RESULTS

During a mean follow-up of 9.6 y, there were 2732 deaths. The mean (±SD) age at baseline was 66.6 ± 9.3 y. Median nut consumption was 1 serving/wk. Multivariable-adjusted HRs (95% CIs) were 1.0 (reference), 0.92 (0.83, 1.01), 0.85 (0.76, 0.96), 0.86 (0.75, 0.98), and 0.74 (0.63, 0.87) for nut consumption of never or <1 serving/mo, 1-3 servings/mo, 1 serving/wk, 2-4 servings/wk, and ≥5 servings/wk, respectively (P-linear trend < 0.0001), after adjustment for age, body mass index, alcohol use, smoking, exercise, prevalent diabetes and hypertension, and intakes of energy, saturated fat, fruit and vegetables, and red meat. In a secondary analysis, results were consistent for cardiovascular disease mortality but only suggestive and non-statistically significant for coronary artery disease and cancer mortality.

CONCLUSION

Our data are consistent with an inverse association between nut consumption and the risk of all-cause and cardiovascular disease mortality in US male physicians.

Resources and biological activities of natural polyphenols

The oxidative stress imposed by reactive oxygen species (ROS) plays an important role in many chronic and degenerative diseases. As an important category of phytochemicals, phenolic compounds universally exist in plants, and have been considered to have high antioxidant ability and free radical scavenging capacity, with the mechanism of inhibiting the enzymes responsible for ROS production and reducing highly oxidized ROS. Therefore, phenolic compounds have attracted increasing attention as potential agents for preventing and treating many oxidative stress-related diseases, such as cardiovascular diseases, cancer, ageing, diabetes mellitus and neurodegenerative diseases. This review summarizes current knowledge of natural polyphenols, including resource, bioactivities, bioavailability and potential toxicity.