Associations between nut consumption and inflammatory biomarkers.
Background: Increased nut consumption has been associated with reduced risk of cardiovascular disease and type 2 diabetes, as well as a healthy lipid profile. However, the associations between nut consumption and inflammatory biomarkers are unclear. Objective: We investigated habitual nut consumption in relation to inflammatory biomarkers in 2 large cohorts of US men and women. Design: We analyzed cross-sectional data from 5013 participants in the Nurses’ Health Study (NHS) and Health Professionals Follow-Up Study (HPFS) who were free of diabetes. Nut intake, defined as intake of peanuts and other nuts, was estimated from food frequency questionnaires, and cumulative averages from 1986 and 1990 in the NHS and from 1990 and 1994 in the HPFS were used. Plasma biomarkers were collected in 1989–1990 in the NHS and 1993–1995 in the HPFS. Multivariate linear regression was used to assess the associations of nut consumption with fasting plasma C-reactive protein (CRP, n = 4941), interleukin 6 (IL-6, n = 2859), and tumor necrosis factor receptor 2 (TNFR2, n = 2905). Results: A greater intake of nuts was associated with lower amounts of a subset of inflammatory biomarkers, after adjusting for demographic, medical, dietary, and lifestyle variables. The relative concentrations (ratios) and 95% CIs comparing subjects with nut intake of ≥5 times/wk and those in the categories of never or almost never were as follows: CRP: 0.80 (0.69, 0.90), P-trend = 0.0003; and IL-6: 0.86 (0.77, 0.97), P-trend = 0.006. These associations remained significant after further adjustment for body mass index. No significant association was observed with TNFR2. Substituting 3 servings of nuts/wk for 3 servings of red meat, processed meat, eggs, or refined grains/wk was associated with significantly lower CRP (all P , 0.0001) and IL-6 (P ranges from 0.001 to 0.017). Conclusion: Frequent nut consumption was associated with a healthy profile of inflammatory biomarkers.
Greater Adherence to the Alternative Healthy Eating Index Is Associated with Lower Incidence of Physical Function Impairment in the Nurses' Health Study.
BACKGROUND: Physical function is integral to healthy aging, in particular as a core component of mobility and independent living in older adults, and is a strong predictor of mortality. Limited research has examined the role of diet, which may be an important strategy to prevent or delay a decline in physical function with aging. OBJECTIVE: We prospectively examined the association between the Alternative Healthy Eating Index-2010 (AHEI-2010), a measure of diet quality, with incident impairment in physical function among 54,762 women from the Nurses' Health Study. METHODS: Physical function was measured by the Medical Outcomes Short Form-36 (SF-36) physical function scale and was administered every 4 y from 1992 to 2008. Cumulative average diet was assessed using food frequency questionnaires, administered approximately every 4 y. We used multivariable Cox proportional hazards models to estimate the HRs of incident impairment of physical function. RESULTS: Participants in higher quintiles of the AHEI-2010, indicating a healthier diet, were less likely to have incident physical impairment than were participants in lower quintiles (P-trend < 0.001). The multivariable-adjusted HR of physical impairment for those in the top compared with those in the bottom quintile of the AHEI-2010 was 0.87 (95% CI: 0.84, 0.90). For individual AHEI-2010 components, higher intake of vegetables (P-trend = 0.003) and fruits (P-trend = 0.02); lower intake of sugar-sweetened beverages (P-trend < 0.001), trans fats (P-trend = 0.03), and sodium (P-trend < 0.001); and moderate alcohol intake (P-trend < 0.001) were each significantly associated with reduced rates of incident physical impairment. Among top contributors to the food components of the AHEI-2010, the strongest relations were found for increased intake of oranges, orange juice, apples and pears, romaine or leaf lettuce, and walnuts. However, associations with each component and with specific foods were generally weaker than the overall score, indicating that overall diet pattern is more important than individual parts. CONCLUSIONS: In this large cohort of older women, a healthier diet was associated with a lower risk of developing impairments in physical function.
More pistachio nuts for improving the blood lipid profile. Systematic review of epidemiological evidence.
Recent evidence suggests that regular intake of nuts may be associated with reduction of all-cause mortality, especially cardiovascular deaths. Among all types of nuts, pistachio displays the most favorable dietary composition. Therefore, we searched Medline and ISI Web of Science to identify interventional studies which evaluated changes of conventional blood lipids after replacing part of normal caloric intake with pistachio nuts in humans. Overall, 9 studies were finally included in our systematical literature review (4 randomized crossover, 3 randomized controlled and 3 prospective). In 6/9 (67%) interventional studies total cholesterol and low-density lipoprotein cholesterol (LDL-C) decreased, whereas high-density lipoprotein cholesterol (HDL-C) increased. In all studies total cholesterol/HDL-C ratio (7/7; 100%) and LDL-C/HDL-C ratio (6/6; 100%) decreased after replacing caloric intake with pistachio nuts for not less than 3 weeks. A significant reduction of triglycerides could only be observed in 2 out of 8 studies (25%). Even more importantly, in no interventional study the intake of pistachio nuts was associated with unfavorable changes of the lipid profile. The results of our literature search provide solid evidence that intake of pistachio nuts may exerts favorable effects on the traditional blood profile, provided that their consumption does not increase the habitual or recommended daily caloric intake. It seems also reasonable to suggest that further studies aimed to investigate the favorable effects of nuts on human diseases should distinguish between one type and the others, since the different nuts exhibit unique dietary composition and may hence produce distinctive biological effects in humans.
Effects of walnut consumption on colon carcinogenesis and microbial community structure.
Walnuts are comprised of a complex array of biologically active constituents with individual cancer-protective properties. Here, we assessed the potential benefit of whole walnut consumption in a mouse tumor bioassay using azoxymethane (AOM). In study 1, a modest reduction (1.3-fold) in tumor numbers was observed in mice fed a standard diet (AIN-76A) containing 9.4% walnuts (15% of total fat). In Study 2, the effects of walnut supplementation were tested in the Total Western Diet (TWD). There was a significant reduction (2.3-fold; p<0.02) in tumor numbers in male mice fed TWD containing 7% walnuts (10.5% of total fat). Higher concentrations of walnuts lacked inhibitory effects, particularly in female mice, indicating there may be optimal levels of dietary walnut intake for cancer prevention. Since components of the Mediterranean diet have been shown to affect the gut microbiome, the effects of walnuts were therefore tested in fecal samples using 16S rRNA gene sequencing. Carcinogen treatment reduced the diversity and richness of the gut microbiome, especially in male mice, which exhibited lower variability and greater sensitivity to environmental changes. Analysis of individual operational taxonomic units (OTUs) identified specific groups of bacteria associated with carcinogen exposure, walnut consumption and/or both variables. Correlation analysis also identified specific OTU-clades that were strongly associated with the presence and number of tumors. Taken together, our results indicate that walnuts afford partial protection to the colon against a potent carcinogenic insult, and this may be due in part to walnut-induced changes to the gut microbiome.
Toxic and essential elements in five tree nuts from Hangzhou market, China.
In this study a total of thirty-five tree nut samples of walnut, pecan, pine seed, hickory nut and torreya were obtained from 5 farm product markets in Hangzhou, China and investigated for essential (Cr, Mn, Fe, Mo, Cu, Zn, Se, and Sr) and toxic (Al, As, Cd and Pb) elements by inductively coupled plasma-mass spectroscopy (ICP-MS). Mean elemental concentrations of different tree nuts were in the following ranges: Cr 0.26 - 0.78 mg kg-1, Mn 42.1 - 174 mg kg-1, Fe 33.7 - 43.9 mg kg-1, Mo 0.11- 0.48 mg kg-1, Cu 10.3 - 17.6 mg kg-1, Zn 21.6 - 56.1 mg kg-1, Se 0.015 - 0.051 mg kg-1, Al 1.44-37.6 mg kg-1, As 0.0062-0.047 mg kg-1, Cd 0.016-0.18 mg kg-1 and Pb 0.0069-0.029 mg kg-1. The estimated provisional tolerable daily intake of Al, As, Cd and Pb was much lower than the provisional tolerable daily intake (PTDI).
A Comparison of Flavor Differences between Pecan Cultivars in Raw and Roasted Forms.
The objective of this research was to explore sensory differences among 8 different pecan cultivars ("Pawnee," "Witte," "Kanza," "Major," "Lakota," "Giles," "Maramec," "Chetopa") in raw and roasted forms. The cultivars were collected from 2 growing seasons (2013 and 2014) and evaluated separately. Trained panelists evaluated each cultivar from each season in raw and roasted forms, measuring intensities of 20 flavor attributes using descriptive analysis. The intensities of 10 of the 20 flavor attributes were higher for the roasted pecans across all cultivars. These included pecan ID, overall nutty, nutty-woody, nutty-grainlike, nutty-buttery, brown, caramelized, roasted, overall sweet, and sweet. The cultivars exhibited significant differences from one another for 8 attributes: pecan ID, nutty-buttery, caramelized, acrid, woody, oily, astringent, and bitter. Each of the cultivars displayed unique flavor profiles with some demonstrating extremes of certain attributes, for example the high astringency of "Lakota" or the buttery characteristics of "Pawnee." These results may help pecan growers and pecan product manufacturers understand flavor differences between different varieties of pecans, both in raw and roasted states, and the changes that occur during this process.
Modeling the survival kinetics of Salmonella in tree nuts for use in risk assessment.
Salmonella has been shown to survive in tree nuts over long periods of time. This survival capacity and its variability are key elements for risk assessment of Salmonella in tree nuts. The aim of this study was to develop a mathematical model to predict survival of Salmonella in tree nuts at ambient storage temperatures that considers variability and uncertainty separately and can easily be incorporated into a risk assessment model. Data on Salmonella survival on raw almonds, pecans, pistachios and walnuts were collected from the peer reviewed literature. The Weibull model was chosen as the baseline model and various fixed effect and mixed effect models were fit to the data. The best model identified through statistical analysis testing was then used to develop a hierarchical Bayesian model. Salmonella in tree nuts showed slow declines at temperatures ranging from 21°C to 24°C. A high degree of variability in survival was observed across tree nut studies reported in the literature. Statistical analysis results indicated that the best applicable model was a mixed effect model that included a fixed and random variation of δ per tree nut (which is the time it takes for the first log10 reduction) and a fixed variation of ρ per tree nut (parameter which defines the shape of the curve). Higher estimated survival rates (δ) were obtained for Salmonella on pistachios, followed in decreasing order by pecans, almonds and walnuts. The posterior distributions obtained from Bayesian inference were used to estimate the variability in the log10 decrease levels in survival for each tree nut, and the uncertainty of these estimates. These modeled uncertainty and variability distributions of the estimates can be used to obtain a complete exposure assessment of Salmonella in tree nuts when including time-temperature parameters for storage and consumption data. The statistical approach presented in this study may be applied to any studies that aim to develop predictive models to be implemented in a probabilistic exposure assessment or a quantitative microbial risk assessment.
The extraction of different proteins in selenium enriched peanuts and their antioxidant properties.
In this study, the selenium enriched peanuts and the different solubility proteins extracted from them were investigated. The dried defatted selenium enriched peanuts (SeP) powder (0.3147 μg/g) had a 2.5-fold higher mean total selenium concentration than general peanuts (GP) power (0.1233 μg/g). The SeP had higher concentration of selenium, manganese and zinc than that of GP, but less calcium. The rate of extraction of protein was 23.39% for peanuts and alkali soluble protein was the main component of protein in SeP, which accounted for 92.82% of total soluble protein and combined selenium was 77.33% of total selenium protein. In different forms of proteins from SeP, the WSePr due to higher concentration of selenium had higher DPPH free-radical scavenging activity, higher reducing activity and longer induction time than other proteins.
Development of a Drinkable, Peanut-Based Dietary Supplement and Comparison of Its Nutritional and Microbiological Qualities with Commercial Products.
This study was undertaken to formulate, using peanuts as a major ingredient, a beverage which will benefit older adults who are at a high risk of protein-energy malnutrition and other health complications, and to compare its nutritional and microbiological qualities to commercial products. Peanuts, rice flour, and flaxseed meal in a ratio of 48.0:49.8:2.2 were mixed with water (20% solids) and cooked into gruel which was sequentially treated with BAN® , (480 KNU-B/g, 75 °C 1 h), Alcalase® (2.4 AU-A/g, 60 °C 1 h), and Flavourzyme® (1000 LAPU/g, 55 °C 1 h) to predigest starch and protein, respectively. The degree of hydrolysis and product viscosity during hydrolysis was measured. The nutritional and microbiological qualities of the product were compared to 10 commercial products. Results indicate that 60% of starch was hydrolyzed while a total of 1.62% protein hydrolysis was observed. Product viscosity reduced from 228.55 to 3.60 cP at the end of hydrolysis. The formulation had no cholesterol and low sodium which was a functional property that was absent in the commercial products. Results of this study suggest that the formulation can be further optimized into a unique product that could cater for the protein needs and other nutritional requirements of older adults.
Use of Cold Atmospheric Plasma to Detoxify Hazelnuts from Aflatoxins.
Aflatoxins, produced by Aspergillus flavus and A. parasiticus, can contaminate different foodstuffs, such as nuts. Cold atmospheric pressure plasma has the potential to be used for mycotoxin detoxification. In this study, the operating parameters of cold atmospheric pressure plasma were optimized to reduce the presence of aflatoxins on dehulled hazelnuts. First, the effect of different gases was tested (N₂, 0.1% O₂ and 1% O₂, 21% O₂), then power (400, 700, 1000, 1150 W) and exposure time (1, 2, 4, and 12 min) were optimized. In preliminary tests on aflatoxin standard solutions, this method allowed to obtain a complete detoxification using a high power for a few minutes. On hazelnuts, in similar conditions (1000 W, 12 min), a reduction in the concentration of total aflatoxins and AFB₁ of over 70% was obtained. Aflatoxins B₁ and G₁ were more sensitive to plasma treatments compared to aflatoxins B₂ and G₂, respectively. Under plasma treatment, aflatoxin B₁ was more sensitive compared to aflatoxin G₁. At the highest power, and for the longest time, the maximum temperature increment was 28.9 °C. Cold atmospheric plasma has the potential to be a promising method for aflatoxin detoxification on food, because it is effective and it could help to maintain the organoleptic characteristics.