The gut microbiota metabolism of pomegranate or walnut ellagitannins yields two urolithin-metabotypes that correlate with cardiometabolic risk biomarkers: comparison between normoweight, overweight-obesity and metabolic syndrome.
BACKGROUND & AIMS: Urolithins are microbial metabolites produced after consumption of ellagitannin-containing foods such as pomegranates and walnuts. Parallel to isoflavone-metabolizing phenotypes, ellagitannin-metabolizing phenotypes (urolithin metabotypes A, B and 0; UM-A, UM-B and UM-0, respectively) can vary among individuals depending on their body mass index (BMI), but correlations between urolithin metabotypes (UMs) and cardiometabolic risk (CMR) factors are unexplored. We investigated the association between UMs and CMR factors in individuals with different BMI and health status. METHODS: UM was identified using UPLC-ESI-qToF-MS in individuals consuming pomegranate or nuts. The associations between basal CMR factors and the urine urolithin metabolomic signature were explored in 20 healthy normoweight individuals consuming walnuts (30 g/d), 49 healthy overweight-obese individuals ingesting pomegranate extract (450 mg/d) and 25 metabolic syndrome (MetS) patients consuming nuts (15 g-walnuts, 7.5 g-hazelnuts and 7.5 g-almonds/d). RESULTS: Correlations between CMR factors and urolithins were found in overweight-obese individuals. Urolithin-A (mostly present in UM-A) was positively correlated with apolipoprotein A-I (P ≤ 0.05) and intermediate-HDL-cholesterol (P ≤ 0.05) while urolithin-B and isourolithin-A (characteristic from UM-B) were positively correlated with total-cholesterol, LDL-cholesterol (P ≤ 0.001), apolipoprotein B (P ≤ 0.01), VLDL-cholesterol, IDL-cholesterol, oxidized-LDL and apolipoprotein B:apolipoprotein A-I ratio (P ≤ 0.05). In MetS patients, urolithin-A only correlated inversely with glucose (P ≤ 0.05). Statin-treated MetS patients with UM-A showed a lipid profile similar to that of healthy normoweight individuals while a poor response to lipid-lowering therapy was observed in MB patients. CONCLUSIONS: UMs are potential CMR biomarkers. Overweight-obese individuals with UM-B are at increased risk of cardiometabolic disease, whereas urolithin-A production could protect against CMR factors. Further research is warranted to explore these associations in larger cohorts and whether the effect of lipid-lowering drugs or ellagitannin-consumption on CMR biomarkers depends on individuals' UM.
Acute Peanut Consumption Alters Postprandial Lipids and Vascular Responses in Healthy Overweight or Obese Men.
Background: Postprandial hyperlipidemia is associated with impaired endothelial function. Peanut consumption favorably affects the lipid and lipoprotein profile; however, the effects on endothelial function remain unclear. Objective: The purpose of the study was to evaluate the effects of acute peanut consumption as part of a high-fat meal on postprandial endothelial function. Methods: We conducted a randomized, controlled, crossover postprandial study to evaluate the effect of acute peanut consumption on postprandial lipids and endothelial function as assessed by flow-mediated dilatation (FMD) of the brachial artery in 15 healthy overweight or obese men [mean age: 26.7 y; mean body mass index (in kg/m2): 31.4]. Participants consumed, in a randomized order, a peanut meal containing 3 ounces (85 g) ground peanuts (1198 kcal; 40.0% carbohydrate, 47.7% fat, 19.4% saturated fat, 13.2% protein) and a control meal matched for energy and macronutrient content. Meals were in the form of a shake, scheduled ≥1 wk apart. Lipids, lipoproteins, glucose, and insulin were measured at baseline (0 min) and at 30, 60, 120, and 240 min after shake consumption. FMD was measured at baseline and at 240 min. Results: Acute peanut consumption blunted the serum triglyceride (TG) response 120 and 240 min after consumption compared with the control meal (means ± SEMs—120 min: 188.9 ± 19.4 compared with 197.5 ± 20.7 mg/dL; 240 min: 189.9 ± 24.3 compared with 197.3 ± 18.4 mg/dL; P < 0.05 for both). Total, LDL, and HDL cholesterol and glucose and insulin responses were similar between the test meals. Compared with baseline, only the control meal significantly decreased FMD at 240 min (control: −1.2% ± 0.5%; P = 0.029; peanut: −0.6% ± 0.5%; P = 0.3). Participants with higher baseline total (>150 mg/dL) and LDL (>100 mg/dL)-cholesterol concentrations showed a significant decrease in FMD after the control meal (−1.8%, P = 0.017; −2.0%, P = 0.038), whereas the peanut meal maintained endothelial function in all participants irrespective of total- and LDL-cholesterol concentrations. Conclusion: The inclusion of 85 g peanuts (3 ounces) as part of a high-fat meal improved the postprandial TG response and preserved endothelial function in healthy overweight or obese men. This trial was registered at clinicaltrials.gov as NCT01405300.
Food groups and risk of type 2 diabetes mellitus: a systematic review and meta-analysis of prospective studies.
The aim of this systematic review and meta-analysis was to synthesize the knowledge about the relation between intake of 12 major food groups and risk of type 2 diabetes (T2D). We conducted a systematic search in PubMed, Embase, Medline (Ovid), Cochrane Central, and Google Scholar for prospective studies investigating the association between whole grains, refined grains, vegetables, fruits, nuts, legumes, eggs, dairy, fish, red meat, processed meat, and sugar-sweetened beverages (SSB) on risk of T2D. Summary relative risks were estimated using a random effects model by contrasting categories, and for linear and non-linear dose-response relationships. Six out of the 12 food-groups showed a significant relation with risk of T2D, three of them a decrease of risk with increasing consumption (whole grains, fruits, and dairy), and three an increase of risk with increasing consumption (red meat, processed meat, and SSB) in the linear dose-response meta-analysis. There was evidence of a non-linear relationship between fruits, vegetables, processed meat, whole grains, and SSB and T2D risk. Optimal consumption of risk-decreasing foods resulted in a 42% reduction, and consumption of risk-increasing foods was associated with a threefold T2D risk, compared to non-consumption. The meta-evidence was graded "low" for legumes and nuts; "moderate" for refined grains, vegetables, fruit, eggs, dairy, and fish; and "high" for processed meat, red meat, whole grains, and SSB. Among the investigated food groups, selecting specific optimal intakes can lead to a considerable change in risk of T2D.
Prediction of cashew nut allergy in sensitised children.
As an alternative to the costly, time-consuming and possibly stressful double-blind, placebo-controlled challenge (DBPCFC) test, a model to predict the risk of cashew nut allergy was studied incorporating patient characteristics, standard diagnostic parameters (specific IgE (sIgE) and Skin Prick Test (SPT)) as well as component resolved diagnosis (CRD).
A healthier US diet could reduce greenhouse gas emissions from both the food and health care systems.
The standard US diet contributes to greenhouse gas emissions (GHGE) from both the food system, and from the health system through its contribution to non-communicable diseases. To estimate the potential for diet change to reduce GHGE and improve public health, we analyzed the effect of adopting healthier model diets in the USA on the risk of disease, health care costs, and GHGE. We found that adoption of healthier diets reduced the relative risk of coronary heart disease, colorectal cancer, and type 2 diabetes by 20–45%, US health care costs by US$B 77–93 per year, and direct GHGE by 222–826 kg CO2e capita−1 year−1 (69–84 kg from the health care system, 153–742 kg from the food system). Emission reductions were equivalent to 6–23% of the US Climate Action Plan’s target of a 17% reduction in 2005 GHGE by 2020, and 24–134% of California’s target of 1990 GHGE levels by 2020. However, there is potential for investment of health care savings to result in rebound up to and greater than 100%, which would increase net GHGE. Given the urgency of improving public health and of mitigating GHGE over the short term, the potential contribution of diet change, and the options for reducing rebound, deserve more research in support of policy.
Consumption of nuts and seeds and telomere length in 5,582 men and women of the National Health and Nutrition Examination Survey (NHANES).
OBJECTIVES: Consumption of nuts and seeds is associated favorably with all-cause mortality. Nuts and seeds could reduce disease and prolong life by influencing telomeres. Telomere length is a good indicator of the senescence of cells. The purpose of the present study was to determine the relationship between nuts and seeds intake and leukocyte telomere length, a biomarker of biologic aging. DESIGN: Cross-sectional. SETTING AND PARTICIPANTS: A total of 5,582 randomly selected men and women from the National Health and Nutrition Examination Survey (NHANES), 1999-2002, were studied. MEASUREMENTS: DNA was obtained via blood samples. Telomere length was assessed using the quantitative polymerase chain reaction method. A validated, multi-pass, 24-h recall dietary assessment, administered by NHANES, was employed to quantify consumption of nuts and seeds. RESULTS: Nuts and seeds intake was positively and linearly associated with telomere length. For each 1-percent of total energy derived from nuts and seeds, telomere length was 5 base pairs longer (F=8.6, P=0.0065). Given the age-related rate of telomere shortening was 15.4 base pairs per year (F=581.1, P<0.0001), adults of the same age had more than 1.5 years of reduced cell aging if they consumed 5% of their total energy from nuts and seeds. CONCLUSIONS: Consumption of nuts and seeds accounts for meaningful decreases in biologic aging and cell senescence. The findings reinforce the recommendations of the 2015-2020 Dietary Guidelines for Americans, which encourage the consumption of nuts and seeds as part of a healthy diet.
Characteristics of tree nut challenges in tree nut allergic and tree nut sensitized individuals.
BACKGROUND: Characteristics and outcomes of tree nut (TN) oral food challenges (OFCs) in patients with TN allergy or sensitization alone are poorly studied. OBJECTIVE: To determine the relation between TN sensitization levels and OFC outcomes. METHODS: Open TN OFCs performed from 2007 through 2015 at a referral center were analyzed to compare outcome based on skin prick test (SPT) wheal size, food-specific immunoglobulin E (sIgE), peanut co-allergy, and TN sensitization only vs TN allergy with sensitization to other TNs. Delayed OFC was defined as longer than 12 months from the time of an sIgE level lower than 2 kUA/L. RESULTS: Overall passage rate was 86% for 156 TN OFCs in 109 patients (54 almond, 28 cashew, 27 walnut, 18 hazelnut, 14 pecan, 13 pistachio, and 2 Brazil nut). Passage rates were 76% (n = 67) in patients with a history of TN allergy who were challenged to another TN to which they were sensitized and 91% (n = 65) in those with TN sensitization only (mean sIgE 1.53 kUA/L; range 0.35-9.14). Passage rates were 89% (n = 110 of 124) for a TN sIgE level lower than 2 kUA/L and 69% (11 of 16) for a TN sIgE level of at least 2 kUA/L. In 44 challenges in patients with peanut allergy and TN co-sensitization, the TN OFC passage rate was 96%. In 41 TN OFCs with a TN SPT wheal size of at least 3 mm, 61% passed, with a mean wheal size of 4.8 mm (range 3-11) in those passing vs 9 mm (range 3-20) in those failing. CONCLUSION: TN challenges are frequently passed in patients with TN sensitization with or without a history of TN reactivity despite a TN SPT wheal of at least 3 mm or a TN sIgE level of at least 2 kUA/L. Nearly all patients with peanut allergy and TN co-sensitization passed the TN challenge, questioning the clinical relevance of "co-allergy."
Dried Plums, Prunes and Bone Health: A Comprehensive Review.
The 2015-2020 Dietary Guidelines for Americans advocate for increasing fruit intake and replacing energy-dense foods with those that are nutrient-dense. Nutrition across the lifespan is pivotal for the healthy development and maintenance of bone. The National Osteoporosis Foundation estimates that over half of Americans age 50+ have either osteoporosis or low bone mass. Dried plums, also commonly referred to as prunes, have a unique nutrient and dietary bioactive profile and are suggested to exert beneficial effects on bone. To further elucidate and summarize the potential mechanisms and effects of dried plums on bone health, a comprehensive review of the scientific literature was conducted. The PubMed database was searched through 24 January 2017 for all cell, animal, population and clinical studies that examined the effects of dried plums and/or extracts of the former on markers of bone health. Twenty-four studies were included in the review and summarized in table form. The beneficial effects of dried plums on bone health may be in part due to the variety of phenolics present in the fruit. Animal and cell studies suggest that dried plums and/or their extracts enhance bone formation and inhibit bone resorption through their actions on cell signaling pathways that influence osteoblast and osteoclast differentiation. These studies are consistent with clinical studies that show that dried plums may exert beneficial effects on bone mineral density (BMD). Long-term prospective cohort studies using fractures and BMD as primary endpoints are needed to confirm the effects of smaller clinical, animal and mechanistic studies. Clinical and prospective cohort studies in men are also needed, since they represent roughly 29% of fractures, and likewise, diverse race and ethnic groups. No adverse effects were noted among any of the studies included in this comprehensive review. While the data are not completely consistent, this review suggests that postmenopausal women may safely consume dried plums as part of their fruit intake recommendations given their potential to have protective effects on bone loss.
Association of Clinical Reactivity with Sensitization to Allergen Components in Multifood-Allergic Children.
BACKGROUND: Thirty percent of children with food allergies have multiple simultaneous allergies; however, the features of these multiple allergies are not well characterized serologically or clinically. OBJECTIVE: We comprehensively evaluated 60 multifood-allergic patients by measuring serum IgE to key allergen components, evaluating clinical histories and medication use, performing skin tests, and conducting double-blind, placebo-controlled food challenges (DBPCFCs). METHODS: Sixty participants with multiple food allergies were characterized by clinical history, DBPCFCs, total IgE, specific IgE, and component-resolved diagnostics (IgE and IgG4) data. The food allergens tested were almond, egg, milk, sesame, peanut, pecan, walnut, hazelnut, cashew, pistachio, soy, and wheat. RESULTS: Our data demonstrate that of the reactions observed during a graded DBPCFC, gastrointestinal reactions occurred more often in boys than in girls, as well as in individuals with high levels of IgE to 2S albumins from cashew, walnut, and hazelnut. Certain food allergies often occurred concomitantly in individuals (ie, cashew/pistachio and walnut/pecan/hazelnut). IgE testing to components further corroborated serological relationships between and among these clustered food allergies. CONCLUSIONS: Associations of certain food allergies were shown by DBPCFC outcomes as well as by correlations in IgE reactivity to structurally related food allergen components. Each of these criteria independently demonstrated a significant association between allergies to cashew and pistachio, as well as among allergies to walnut, pecan, and hazelnut.
The need to revisit ochratoxin A risk in light of diabetes, obesity, and chronic kidney disease prevalence.
Ochratoxin A (OTA) is a mycotoxin, or fungal toxin, that contaminates multiple foodstuffs worldwide. Affected commodities include oats, wheat, maize, barley, raisins and other dried vine fruits, wine, beer, coffee, and cocoa. Although OTA has been shown to cause kidney disease, including kidney cancer, in multiple animal species, the impact of dietary OTA on human health from a global perspective has been less clear. Several epidemiological studies suggest an association between OTA exposure and human kidney disease, but evidence of causality has been limited. Nonetheless, because OTA is common in so many foodstuffs and may play a role in kidney disease, we consider it important to improve the body of evidence surrounding OTA's adverse effects to humans, as well as human dietary exposures in different parts of the world. This is especially true in the light of increasing type 2 diabetes and obesity prevalence worldwide; both conditions frequently lead to chronic kidney disease (CKD), and may synergize with dietary OTA exposure to increase CKD risk.