Tree Nut Consumption Research Articles

Impact of Mediterranean Diet Pattern Adherence on the Physical Component of Health-Related Quality of Life in Middle-Aged and Older Active Adults.

Background/Objectives: The Mediterranean dietary pattern (MedDiet) has numerous health benefits, particularly in preventing chronic diseases and improving well-being. Given the ageing population, understanding its impact on older adults' physical health is essential. This study examines how adherence to the MedDiet influences the physical component (Comp-p) of health-related quality of life (HRQoL) across various age groups, providing insights for tailored dietary interventions. Methods: A cross-sectional study was conducted with active adults aged 41-80, categorised into four age groups (41-50, n = 116; 51-60, n = 225; 61-70, n = 135; 71-80, n = 44). Data were collected using the SF-36 and MEDAS questionnaires. Com-p scores were analysed based on MedDiet adherence (poor or good) and age. Results: In the 71-80 age group, a significant correlation was found between Comp-P and MedDiet adherence (r = 0.367, p = 0.014), with significantly higher Com-P scores in the good adherence group (50.10 ± 7.39) compared to the poor group (44.46 ± 7.73; p = 0.015; d = 0.74). The loss of adherence to the Mediterranean diet in this age group was attributed to low consumption of vegetables (36.36%), tree nuts (47.73%), legumes (50.00%), fish (52.27%), and fruit (56.82%). Conclusions: In individuals aged 71-80, lower adherence to the Mediterranean diet is associated with a decline in self-perceived physical health, attributed to the reduced intake of fresh vegetables, legumes, fish, and fruit. These findings emphasise the importance of promoting Mediterranean dietary adherence in later life to maintain optimal physical well-being.

Unveiling the "hidden quality" of the walnut pellicle: a precious source of bioactive lipids.

Tree nut consumption has been widely associated with various health benefits, with walnuts, in particular, being linked with improved cardiovascular and neurological health. These benefits have been attributed to walnuts' vast array of phenolic antioxidants and abundant polyunsaturated fatty acids. However, recent studies have revealed unexpected clinical outcomes related to walnut consumption, which cannot be explained simply with the aforementioned molecular hallmarks. With the goal of discovering potential molecular sources of these unexplained clinical outcomes, an exploratory untargeted metabolomics analysis of the isolated walnut pellicle was conducted. This analysis revealed a myriad of unusual lipids, including oxylipins and endocannabinoids. These lipid classes, which are likely present in the pellicle to enhance the seeds' defenses due to their antimicrobial properties, also have known potent bioactivities as mammalian signaling molecules and homeostatic regulators. Given the potential value of this tissue for human health, with respect to its "bioactive" lipid fraction, we sought to quantify the amounts of these compounds in pellicle-enriched waste by-products of mechanized walnut processing in California. An impressive repertoire of these compounds was revealed in these matrices, and in notably significant concentrations. This discovery establishes these low-value agriculture wastes promising candidates for valorization and translation into high-value, health-promoting products; as these molecules represent a potential explanation for the unexpected clinical outcomes of walnut consumption. This "hidden quality" of the walnut pellicle may encourage further consumption of walnuts, and walnut industries may benefit from a revaluation of abundant pellicle-enriched waste streams, leading to increased sustainability and profitability through waste upcycling.

Association of Tree Nut Consumption with Cardiovascular Disease and Cardiometabolic Risk Factors and Health Outcomes in US Adults: NHANES 2011–2018

BackgroundTree nuts are nutrient dense, and their consumption has been associated with improvements in health outcomes. ObjectiveTo estimate the usual tree nut intake and examine the association between tree nut consumption and cardiometabolic (CM) health outcomes in a nationally representative sample of US adults. MethodsCross-sectional data were analyzed from a sample of 18,150 adults aged ≥ 20y who provided at least one reliable 24-h dietary recall and had complete data for the variables of interest in the NHANES 2011–2018. Tree nut consumers were defined as those consuming ≥ ¼ ounce/d (7.09 g). The National Cancer Institute Method was used to estimate the usual tree nut intake among consumers. Measurement error calibrated regression models were used to assess the association between tree nut consumption and each health outcome of interest. ResultsApproximately 8% of all participants (n = 1238) consumed tree nuts and had a mean ± SE usual intake of 39.5 ± 1.8 g/d. Tree nut consumers were less likely to have obesity (31% vs. 40%, P < 0.001) and low high-density lipoprotein cholesterol (22% vs. 30%, P < 0.001) compared with nonconsumers. Moreover, tree nut consumers had a lower mean waist circumference (WC) (97.1 ± 0.7 vs. 100.5 ± 0.3 cm, P < 0.001) and apolipoprotein B (87.5 ± 1.2 vs. 91.8 ± 0.5 mg/dL, P = 0.004) than nonconsumers. After adjusting models for demographics and lifestyle covariates, the difference in WC between average intake (33.7 g/d) and low threshold intake (7.09/g) of tree nuts was -1.42 ± 0.58 cm (P = 0.005). ConclusionsMost US adults do not consume tree nuts, yet modest consumption was associated with decreased prevalence of cardiovascular disease and CM risk factors and improvement for some health outcome measures.

Tree Nut and Peanut Consumption and Risk of Cardiovascular Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Cardiovascular disease (CVD) is the leading cause of death globally. Habitual consumption of tree nuts and peanuts is associated with cardioprotective benefits. Food-based dietary guidelines globally recommend nuts as a key component of a healthy diet. This systematic review and meta-analysis were conducted to examine the relationship between tree nut and peanut consumption and risk factors for CVD in randomized controlled trials (RCTs) (PROSPERO: CRD42022309156). MEDLINE, PubMed, CINAHL, and Cochrane Central databases were searched up to 26 September, 2021. All RCT studies that assessed the effects of tree nut or peanut consumption of any dose on CVD risk factors were included. Review Manager software was used to conduct a random effect meta-analysis for CVD outcomes from RCTs. Forest plots were generated for each outcome, between-study heterogeneity was estimated using the I2 test statistic and funnel plots and Egger's test for outcomes with ≥10 strata. The quality assessment used the Health Canada Quality Appraisal Tool, and the certainty of the evidence was assessed using grading of recommendations assessment, development, and evaluation (GRADE). A total of 153 articles describing 139 studies (81 parallel design and 58 cross-over design) were included in the systematic review, with 129 studies in the meta-analysis. The meta-analysis showed a significant decrease for low-density lipoprotein (LDL) cholesterol, total cholesterol (TC), triglycerides (TG), TC:high-density lipoprotein (HDL) cholesterol, LDL cholesterol:HDL cholesterol, and apolipoprotein B (apoB) following nut consumption. However, the quality of evidence was "low" for only 18 intervention studies. The certainty of the body of evidence for TC:HDL cholesterol, LDL cholesterol:HDL cholesterol, and apoB were "moderate" because of inconsistency, for TG were "low," and for LDL cholesterol and TC were "very low" because of inconsistency and the likelihood of publication bias. The findings of this review provide evidence of a combined effect of tree nuts and peanuts on a range of biomarkers to create an overall CVD risk reduction.

U.S. Consumer Practices of Homemade Nut-based Dairy Analogs and Soaked Nuts

Tree nuts, a low-moisture food, are typically perceived as being a low risk for foodborne illness. In the past five decades, the consumption of tree nuts (dry, soaked, or as nut-based dairy analogs [NBDA]) has increased along with corresponding foodborne illness outbreaks and recalls associated with these products. We developed an online survey to assess tree nut handling practices of U.S. consumers, and to select study participants who have soaked tree nuts and/or made NBDA at home. We distributed our initial survey questions in October 2021 to a convenience sample (n = 12) to test for clarity and comprehension. In January 2022, participants (n = 981) who met the criteria completed the survey. The most popular soaked tree nuts were almonds (54%), followed by cashews (36%), walnuts (32%), and pistachios (22%). Participants soaked tree nuts for direct consumption (67%) and during the preparation of NBDA (80%). Participants soaked tree nuts under refrigerated conditions for 1–24 h (22%), on the countertop at room temperature (est. 65–75°F [18–24°C]) for 1–5 h (21%), or at room temperature for 12 h or more (6%); 16% used a hot or boiling water, short time treatment. Some participants added acid (28%) or salt (25%) to the soaking water. Among those participants who dried their tree nuts after soaking (63%), 89% reported drying at a temperature lower than 46°C (115°F). Some participants (34%) used their tree nuts to make fermented dairy analogs (e.g., “cheese” or “yogurt”) by adding “probiotics” (56–86%) or a yogurt starter culture (37–99%), respectively, and then, most frequently, holding at or below 20°C (68°F) for 12 h or less (29%). The safety of many of these practices has not been adequately investigated, but the findings of this study will inform future risk assessment and risk modeling studies on tree nut food safety in home kitchen settings.

Characteristics of tree nut, peanut, and seed consumption in the eastern Mediterranean region

Nuts and seeds are among the most common causes of food allergy (FA), and consumption differences across cultures and geographic regions are thought to account for the diversity of these allergies. Caregivers of infants (age 12-24 months) with or without FA were questioned in face-to-face interviews to identify the nut and seed consumption practices in the household, during pregnancy, breastfeeding, and early childhood. Of the 171 infants (median age: 17.3 months) included in the study, 75 were healthy and 96 had FA. More than two-thirds of the infants in the whole group started to be fed with walnuts, sesame/tahini, hazelnuts, almonds, and sunflower seeds. The percentages of healthy infants who were not fed with tree nuts, seeds, and peanuts were 4%, 4%, and 49.3%, respectively, for the healthy infants, and 11.8%, 11.8%, and 67.8% for those with FA. In the FA group, sesame and peanut consumption was initiated at a younger age, and walnut, hazelnut, and almond consumption at an older age compared to the healthy infants (p < 0.05 for each). Walnuts and sesame/tahini were the most consumed nuts at home, and peanuts and pumpkin seeds were the least consumed. Mothers reported that they increased tree nut consumption during pregnancy due to their positive effect on health and sesame/tahini consumption during breastfeeding to increase breast milk, respectively. The uniqueness of Turkish culinary culture is characterized by the frequent consumption of tree nuts and seeds, with further increases during pregnancy/lactation and early introduction to the diet of infants.

Mixed Nuts as Healthy Snacks: Effect on Tryptophan Metabolism and Cardiovascular Risk Factors.

We recently demonstrated that the consumption of mixed tree nuts (MTNs) during caloric restriction decreased cardiovascular risk factors and increased satiety. Tryptophan (Trp) metabolism has been indicated as a factor in cardiovascular disease. Here, we investigated the effect of MTNs on Trp metabolism and the link to cardiovascular risk markers. Plasma and stool were collected from 95 overweight individuals who consumed either MTNs (or pretzels) daily as part of a hypocaloric weight loss diet for 12 weeks followed by an isocaloric weight maintenance program for an additional 12 weeks. Plasma and fecal samples were evaluated for Trp metabolites by LC-MS and for gut microbiota by 16S rRNA sequencing. Trp-kynurenine metabolism was reduced only in the MTNs group during weight loss (baseline vs. week 12). Changes in Trp-serotonin (week 24) and Trp-indole (week 12) metabolism from baseline were increased in the MTNs group compared to the pretzel group. Intergroup analysis between MTN and pretzel groups does not identify significant microbial changes as indicated by alpha diversity and beta diversity. Changes in the relative abundance of genus Paludicola during intervention are statistically different between the MTNs and pretzel group with p < 0.001 (q = 0.07). Our findings suggest that consumption of MTNs affects Trp host and microbial metabolism in overweight and obese subjects.

The Effects of Tree Nut and Peanut Consumption on Energy Compensation and Energy Expenditure: A Systematic Review and Meta-Analysis.

Nut consumption is not associated with a higher body weight, and potential energy-regulating mechanisms may include a reduced subsequent energy intake and increased EE. The aim of this study was to examine the effect of tree nut and peanut consumption on energy intake, compensation, and expenditure. PubMed, MEDLINE, CINAHL, Cochrane, and Embase databases were searched from inception to June 2, 2021. Human studies with adults aged ≥18 y older were included. Energy intake and compensation studies were restricted to acute effects (intervention duration of ≤24 h), whereas intervention duration was not limited for EE studies. Random effects meta-analyses were conducted to explore weighted mean differences in REE. Twenty-eight articles from 27 studies (16 energy intake studies, 10 EE studies, and 1 study investigating both) with 1121 participants were included in this review, with a variety of nut types addressed (almonds, Brazil nuts, cashews, chestnuts, hazelnuts, peanuts, pistachios, walnuts, and mixed nuts). Energy compensation occurred after nut-containing loads (range: -280.5% to +176.4%) and the degree of compensation varied depending on the form (whole and chopped) and how they were consumed (alone and within a meal). The meta-analyses identified a nonsignificant increase in REE associated with nut consumption (weighted mean difference: 28.6 kcal/d; 95% CI: -10.7, 67.8 kcal/d). This study provided support for energy compensation as a potential mechanism for a lack of association between nut consumption and body weight, whereas no evidence was found for EE as an energy-regulating mechanism of nuts. This review was registered at PROSPERO as CRD42021252292.

The effects of tree nut and peanut consumption on energy compensation and energy expenditure: a systematic review and meta-analysis

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Mixed Tree Nuts, Cognition, and Gut Microbiota: A 4-Week, Placebo-Controlled, Randomized Crossover Trial in Healthy Nonelderly Adults

Beneficial effects of nut supplementation on cognitive function have previously been demonstrated in young and older adults. Alterations to gut microbiota have also been shown following tree nut consumption. However, no data exists on the effects of nuts on cognition and intestinal microbial communities assessed within the same study. The study aimed to examine the effects of daily consumption of tree nuts for 4 wk on cognitive function (primary outcome), mood, metabolomics, and gut microbial species (secondary outcomes) in healthy, nonelderly adults. This randomized, placebo-controlled, double-blind, counterbalanced crossover study assessed the effects of 4 wk of supplementation with 30 g/d mixed tree nuts versus placebo on cognition and mood in 79 healthy adults aged 18-49 y. Metabolic responses, gut bacterial community structure, and the potential for these to impact cognition were explored using a multi-omic approach. Bacterial community analysis was conducted in Quantitative Insights Into Microbial Ecology 2 (QIIME2). Mixed model analysis indicated that nut consumption led to significant improvements to accuracy (placebo M = 92.2% compared with NUTS M = 94.5%; P = 0.019) and speed of response (placebo M = 788 ms compared with NUTS M = 757 ms; P = 0.004) on a picture recognition task. No significant changes to bacterial community α or β diversity were observed when comparing nut consumption to the placebo arm. However, an unclassified Lachnospiraceae amplicon sequence variant (ASV) was significantly enriched in participants when supplemented with nuts (P = 0.015). No correlations were observed between the changes to picture recognition and the changes to the unclassified Lachnospiraceae ASV. There were no significant changes to the urinary metabolome. These findings indicate a positive effect of nut on cognition following only 4 wk of consumption in a healthy nonelderly sample, as well as upregulation of a microbial taxa associated with gut health. The effects appear to be independent of one another, but further exploration is required in those experiencing cognitive decline and/or gut dysbiosis.

Processing it all: Starch residues on Jomon Period ground stone from southern Hokkaido, Japan

For the Jomon Period, ground stone technology related to processing activities, such as handstones and querns, are commonly associated with plant foods. In many cases, these tools are considered to be an indicator for the consumption of tree nuts. In this study, ground stone artifacts from 15 sites across southern Hokkaido were analyzed for starchy residues to examine the relationship between grinding tools and economic plant taxa in Jomon daily practices. Overall, 24 of the 76 artifacts examined here had observable starch grains, meaning a large percentage of tools did not appear to have been in contact with starchy plants. The starch types commonly found in underground storage organs (USOs) were the most prominent component of the observed grains, indicating the use of yams, lilies, and other roots or tubers. The evidence for Poaceae grasses, legumes, and nuts is less clear, but present alongside the USO starch granules. These results suggest that grinding implements were not limited to processing plant foods, and would not have been restricted to specific resources, such as nuts.

Differentiated responsibilities of US citizens in the country’s sustainable dietary transition

If widely adopted, the ‘planetary health diet’ (PHD), proposed by the EAT-Lancet Commission, would help to meet ambitious sustainability goals currently jeopardised by excessive and resource intensive food demand. To date, convergence of nations to the PHD has been assessed using average food consumption patterns, overlooking the influence of different consumers within this context. Using self-reported dietary intake data from a snapshot survey of the US we reveal the differentiated responsibilities of US citizens within the country’s adoption of the PHD otherwise hidden by use of country averaged dietary intake data. We show how such a granular analysis of food consumption patterns is critical to identify levers in the sustainable food transition of nations. By combining 7418 individual food intake reports from a representative cross section of the United States (US) with commodity-level impact data we estimate the overshoot of US dietary patterns in relation to the PHD and their impacts across the climate, water and land system. The net environmental impacts of PHD adoption across the US population are quantified based on realistic dietary shifts. We estimate that US overshoot of the PHD is responsible for 70% of the US dietary greenhouse gas (GHG) footprint. However, over 60% of this burden could be eliminated by just 10% of the US population following the PHD. Although we estimate PHD adoption will more than half the US dietary GHG footprint and land footprint, we find it may have unintended consequences on water demand due to increased tree nut consumption. Across almost all food categories, we show that the food choices of the top tier of consumers in the US create, and must bridge the PHD gap. As such, actions by these consumers will be of major consequences to the speed and direction of the country’s sustainable dietary transition. To avoid environmental trade-offs, dietary policies must be scrutinised across multiple sustainability criteria.

Mixed Nuts as Healthy Snack: Effect on Gut Microbiota and Tryptophan Metabolism

ObjectivesWe recently demonstrated that the consumption of mixed tree nuts (MTNs) as part of a hypocaloric diet decreased heart rate and increased satiety. MTNs can be categorized as a high tryptophan (Trp) food and disturbed Trp metabolism has been associated with cardiovascular disease. The fiber and polyphenol content of MTNs have been suggested to affect human health in part through the gut microbiome. Here, we aim to investigate the effect of MTNs on Trp metabolism and the gut microbiome and the link to cardiovascular markers and satiety.MethodsStool and plasma samples at baseline, week 12 and 24 from our recent randomized, controlled, two-arm study were studied. In the study 95 overweight individuals consuming 1.5 oz. of MTNs (n = 56) or pretzel snack (n = 38) daily as part of a hypocaloric (−500 kcal) weight loss diet for 12 weeks followed by an isocaloric weight maintenance program for additional 12 weeks. Trp metabolites kynurenine (KYN), kynurenic acid (KYNA), Trp, indole sulfate (IS), indole propionate (IPA) and indole acetate (IAA) were analyzed by LC-MS and HPLC. Gut microbiota will be analyzed by 16S rRNA sequencing.ResultsAt baseline, a positive correlation was observed between heart rate and serum KYN levels and KYN/Trp ratio, as well as between BMI and KYN/Trp ratio. Compared to baseline, KYN levels were significantly reduced in the MTN group at the end of 12 week weight loss phase (P = 0.04) and returned to baseline concentration after 12 weeks of isocaloric weight maintenance program (baseline vs. week 12 vs. week 24: 357 ± 124 vs. 339 + 103 vs. 362 ± 137 ng/mL), but not in pretzel group (418 + 431 vs. 347 ± 150 vs. 375 + 171 ng/mL). Other Trp metabolites evaluatedwere not changed during intervention in either groups. The gut microbiome analysis is ongoing.ConclusionsWe identified a positive association between Try-KYN metabolism and heart rate and BMI in overweight individuals. MTN consumption may directly affect Trp-KYN metabolism.Funding SourcesInternational Tree Nut Council Nutrition Research and Education Foundation.

Tree Nuts and Peanuts as a Source of Beneficial Compounds and a Threat for Allergic Consumers: Overview on Methods for Their Detection in Complex Food Products.

Consumption of tree nuts and peanuts has considerably increased over the last decades due to their nutritional composition and the content of beneficial compounds. On the other hand, such widespread consumption worldwide has also generated a growing incidence of allergy in the sensitive population. Allergy to nuts and peanuts represents a global relevant problem, especially due to the risk of the ingestion of hidden allergens as a result of cross-contamination between production lines at industrial level occurring during food manufacturing. The present review provides insights on peanuts, almonds, and four nut allergens—namely hazelnuts, walnuts, cashew, and pistachios—that are likely to cross-contaminate different food commodities. The paper aims at covering both the biochemical aspect linked to the identified allergenic proteins for each allergen category and the different methodological approaches developed for allergens detection and identification. Attention has been also paid to mass spectrometry methods and to current efforts of the scientific community to identify a harmonized approach for allergens quantification through the detection of allergen markers.

Changes in body weight in response to pecan-enriched diets with and without substitution instructions: a randomised, controlled trial.

Substantial evidence suggests that regular tree nut consumption does not lead to changes in body weight (BW). However, these studies used a variety of dietary substitution instructions which may confound the interpretation of prior BW outcomes. The purpose of the present study was to examine the impact of daily pecan consumption, with or without isocaloric substitution instructions, on BW and composition. This was an 8-week randomised, controlled trial with three treatments: a nut-free control group (n 32) and two pecan groups. ADD (n 30) consumed pecans (68 g/d) as part of a free-living diet, and SUB (n 31) substituted the pecans (68 g/d) for isocaloric foods from their habitual diet. BW and total body fat percentage (BF) were measured, and theoretical changes in these outcomes if pecans were consumed without compensation were determined. BW increased in all groups across the intervention, and there was a trend (P = 0⋅09) for an increase in ADD (1⋅1 ± 0⋅2 kg) and SUB (0⋅9 ± 0⋅3 kg) compared to control (0⋅3 ± 0⋅2 kg). In addition, there was increased BF in SUB (1⋅0 ± 0⋅3 %; P = 0⋅005) but not ADD (0⋅1 ± 0⋅2 %) or control (-0⋅2 ± 0⋅3 %) There was a large difference in the actual v. theoretical change in BW regardless of pecan treatment (actual: 1⋅1 ± 0⋅2 and 0⋅9 ± 0⋅3 v. theoretical: 3⋅3 ± 0⋅0 and 3⋅2 ± 0⋅0 kg in ADD and SUB, respectively; P < 0⋅001). Furthermore, there was a difference in actual v. theoretical change in BF in ADD (0⋅1 ± 0⋅2 v. 1⋅2 ± 0⋅1 %; P = 0⋅002) but not SUB or control. In conclusion, daily pecan consumption for 8 weeks did not result in significant weight gain, regardless of dietary substitution instructions.

Pistachio Nuts (Pistacia vera L.): Production, Nutrients, Bioactives and Novel Health Effects.

Epidemiological and clinical studies have indicated positive outcomes related to tree nut consumption. Here, we review the production, nutrient, phytochemical composition and emerging research trends on the health benefits of pistachio nuts (Pistacia vera L.). Pistachios are a good source of protein, fiber, monounsaturated fatty acids, minerals and vitamins, as well as carotenoids, phenolic acids, flavonoids and anthocyanins. Polyphenols in pistachios are important contributors to the antioxidant and anti-inflammatory effect, as demonstrated in vitro and in vivo through animal studies and clinical trials. The antimicrobial and antiviral potential of pistachio polyphenols has also been assessed and could help overcome drug resistance. Pistachio consumption may play a role in cognitive function and has been associated with a positive modulation of the human gut microbiota and beneficial effects on skin health. Pistachio polyphenol extracts may affect enzymes involved in glucose regulation and so type 2 diabetes. Taken together, these data demonstrate the health benefits of including pistachios in the diet. Further studies are required to investigate the mechanisms involved.

Tree nut consumption is associated with a lower risk of hyperestrogenism in men

Hyperestrogenism may affect 2% to 8% of men globally. Previous studies indicate that tree nut consumption is associated with sex hormones in women. Whether this is the case in men remains unknown. This study hypothesized that consumption of tree nuts was inversely associated with circulating estradiol and prevalence of hyperestrogenism in men. This cross-sectional study included 3340 men aged ≥20 years from the US National Health and Nutrition Examination Survey from 2013 to 2016. Associations of tree nut consumption with circulating estradiol and prevalence of hyperestrogenism were assessed using weighted linear regression and binary logistic regression, respectively. Among the 3340 men, 207 consumed tree nuts. The mean usual intake of tree nuts among tree nut consumers was 34.2 g/d. Amounts of usual intake of tree nuts were inversely associated with bioavailable estradiol (β=-0.032, P=.037) after adjustment for all confounders. Usual intake of tree nuts of ≥ 30 g/d (vs <30 g/d) or ≥42.52 g/d (vs <42.52 g/d) was associated with a 24% or 7% lower multivariate-adjusted risk of hyperestrogenism, respectively. Further analyses showed that usual intake of tree nuts was positively associated with circulating folate, and the latter was inversely associated with circulating estradiol. In conclusion, higher tree nut consumption was independently associated with lower circulating levels of bioavailable estradiol and a lower risk of hyperestrogenism in men. Further research is needed to verify the effectiveness of using tree nuts to treat hyperestrogenism in men.

Tree nut consumption and prevalence of carotid artery plaques: The National Heart, Lung, and Blood Institute Family Heart Study.

While tree nut consumption has been shown to be cardioprotective, a few studies have examined the relationship between tree nut consumption and carotid atherosclerosis. We tested the hypothesis that tree nut consumption would be inversely related with carotid atherosclerosis in adults. We cross-sectionally analyzed data from 4536 participants of the National Heart, Lung, and Blood Institute (NHLBI) Family Heart Study conducted in the United States. Dietary patterns among participants were variable, tree nut consumption was self-reported using the Food Frequency Questionnaire (FFQ), and B-mode ultrasound of the carotid arteries was used to assess for the presence of carotid artery plaques (primary outcome) and carotid intima media thickness (cIMT). Multivariable logistic regression was used to estimate odds ratio (95% confidence interval) of prevalent carotid artery plaques and linear regression was used to estimate adjusted mean cIMT across categories of nut consumption. The mean age was 52.3years (SD = 13.6), 95.6% of the participants were white, and 54% were female. The median tree nut intake was 1-3 servings/month. Odds ratios (95% CI) for prevalent carotid artery plaques were 1.0 (reference), 1.03 [0.86, 1.4], 0.89 [0.70, 1.13], and 0.96 [0.73, 1.26] for tree nut consumption of almost never, 1-3 times/month, 1/week, and 2+/week, respectively, adjusting for age, sex, race, field center, BMI, smoking status, alcohol consumption, creatinine, energy intake, fruit and vegetable consumption, exercise, and education. In secondary analysis, there was a suggestive inverse association of tree nut consumption with cIMT in the internal carotid artery, but not the common carotid or bifurcation. Our data showed no association between tree nut consumption and prevalence of carotid artery plaques in adults.

Tree nut consumption is associated with higher sex hormone-binding globulin levels in premenopausal US women

Low levels of sex hormone-binding globulin (SHBG) are associated with many diseases including hypertension, diabetes, and polycystic ovarian syndrome. Walnuts increased circulating SHBG in 31 women complicated with polycystic ovarian syndrome. However, whether tree nuts increase SHBG in women in a general population is unknown. It was hypothesized in this study that consumption of tree nuts was positively associated with SHBG levels in women in a general population. This cohort study included 2699 adult women from the 2013- to 2016 US National Health and Nutrition Examination Survey. Tree nut consumers were defined as those who consumed tree nuts on either of the 2 24-hours recall days. Associations of tree nut consumption with SHBG were assessed using least squares regression. Among the 2699 women, 234 were consuming tree nuts. The median SHBG concentrations were 67.1 and 59.3 nmol/L among tree nut consumers and non-consumers, respectively. Tree nut consumption was positively associated with circulating SHBG (β=0.041, P=.018) but not testosterone nor estradiol after adjustment for all tested confounders. Sub-analyses showed that the positive association of tree nuts with SHBG presented in premenopausal women but not in postmenopausal women. Tree nut consumption remained independently associated with higher circulating levels of SHBG in premenopausal women when tree nut consumption was expressed as percentage of energy derived from tree nuts or when tree nut consumption was defined as a tree nut intake of ≥0.25 ounce per day. Future research will verify the effectiveness of using tree nuts to treat low SHBG in premenopausal women in the general population.

The Relationship of Tree Nuts and Peanuts with Adiposity Parameters: A Systematic Review and Network Meta-Analysis.

The network meta-analysis and systematic review conducted aim to comparatively assess the effects of tree nuts and peanuts on body weight (BW), body mass index (BMI), waist circumference (WC), and body fat percentage (BF%). A systematic search up to 31 December 2020 was performed. A random-effects network meta-analysis was conducted following the PRISMA-NMA statement. A total of 105 randomized controlled trials (RCTs) with measures of BW (n = 6768 participants), BMI (n = 2918), WC (n = 5045), and BF% (n = 1226) were included. The transitivity assumption was met based on baseline characteristics. In the comparisons of nut consumption versus a control diet, there was no significant increase observed in any of the adiposity-related measures examined except for hazelnut-enriched diets, which raised WC. Moreover, almond-enriched diets significantly reduced WC compared to the control diet and to the pistachio-, mixed nuts-, and hazelnut-enriched diets. In subgroup analyses with only RCTs, designed to assess whether nut consumption affected weight loss, almonds were associated with reduced BMI and walnuts with reduced %BF. The evidence supports that: (1) tree nut and peanut consumption do not influence adiposity, and (2) compared to a control diet, the consumption of almond-enriched diets was associated with a reduced waist circumference.