Oral Food Challenge in Children with Tree Nut and Peanut Allergy: The Predictive Value of Diagnostic Tests
Food allergy (FA) affects approximately 6-8% of young children, with a peak prevalence at approximately one year of age. Tree nut and peanut allergies are among the main causes of anaphylaxis in the world. The gold standard for the diagnosis of FAs is the oral food challenge (OFC). Other diagnostic tests used in the clinical practice are skin prick tests (SPTs) and laboratory tests to measure out the presence of serum specific IgE (sIgE). In this narrative review, we collect the current evidence of the predictive value (PV) of SPTs and sIgE for the outcome of the OFCs. In literature, data are conflicting as to whether increasing sIgE concentration and wheal size in SPTs correlate with OFC outcomes. Most studies included in our review have shown that in vivo and in vitro tests may predict OFC outcomes with variable PV, but data are not conclusive; therefore, the OFC currently remains the gold standard for FA diagnosis. https://doi.org/10.3390/diagnostics14182069
Peanut allergen characterization and allergenicity throughout development
Introduction: Peanut allergy (PA) in children is a major concern. There is a need for better biological material for both diagnosis and oral immunotherapy (OIT) treatments. The unique state of seeds at early reproductive stages may affect the allergenicity of storage proteins, and impact clinical diagnostic and OIT protocols. The objective of this study was to evaluate the major allergen content in sequential seed developmental stages and monitor allergenicity via specific IgE binding quantification and skin prick testing. Methods: Seeds were collected from peanut plants and sorted into five developmental stages: initial (S1), developing (S2), full-size without coloration (S3), full-size with coloration (S4), and fully mature (S5) seeds. Samples were characterized by RNA-Seq, ELISA, and immunohistochemistry. Lyophilized, ground preparations were used for evaluation of skin test responses in sixty challenge-proven PA children. Results: Gene expression, protein content, and specific IgE binding of allergenic proteins increased throughout seed maturation and development. An expression bias towards the less allergenic A-genome copy of the major allergen Ara h 2 was found in earlier stages, especially in stage S2. Immunohistochemical staining showed that Ara h 2 is more dispersed in the cell and less accumulated within organized bodies at stage S2 versus stage S4. Significant differences were found in mean wheal responses between the commercial peanut extract (equivalent to stage S5) and stages S1 and S2, but not with stage S4, upon skin prick testing in subjects with PA. Discussion: The observed decrease in peanut-specific IgE binding of immature peanut seeds may be a result not only of decreased amounts of allergenic proteins, but also of profound changes in seed composition and conformation. This may be significant for developing a safer and more effective peanut OIT protocol. https://doi.org/10.3389/falgy.2024.1395834
Epicutaneous immunotherapy for the treatment of peanut allergy
Peanut allergy treatment options remain limited, but novel approaches are being studied, including epicutaneous immunotherapy (EPIT). EPIT uses the cutaneous immune system to promote tolerance to food allergens. Viaskin™ Peanut, an approach to EPIT in late-stage clinical development uses an occlusive patch with a condensation chamber that enables natural epidermal water loss to solubilize dry antigen on the patch, which is then absorbed and captured by skin Langerhans cells. This form of EPIT does not require disruption of the skin barrier, thus avoiding a proinflammatory cytokine response by targeting the nonvascularized epidermis and limiting systemic allergen exposure. Extensive preclinical research suggests that Viaskin Peanut has a distinct mechanism of desensitization, including the potential for disease modification, driven by a unique population of regulatory T cells. Numerous clinical studies of Viaskin Peanut have demonstrated desensitization and reductions in reaction severity, particularly in children aged 1 through 11 years, as well as a favorable safety profile with mostly mild-to-moderate skin reactions that were observed to decrease over time. EPIT with Viaskin Peanut may be a potential therapeutic option for peanut allergy that is clinically practical with long-term efficacy and tolerability. https://doi.org/10.1111/all.16324
Safety and feasibility of peanut, tree nut, and sesame oral immunotherapy in infants and toddlers in a real-world setting
Background: Oral immunotherapy (OIT) for food allergy has been largely studied in older children within the context of clinical trials, and its availability has historically been limited for younger patients with food allergy. Data has shown that the most impact may actually be seen with the use of OIT in younger infants and toddlers. Objective: To evaluate the safety and feasibility of OIT in subjects younger than 24 months in a real-world setting using commercially available food products. Methods: This was a retrospective study of subjects 24 months and younger initiated on OIT for peanut, tree nut, or sesame allergy within the Scripps Clinic allergy department. Medical records were reviewed for data regarding initial oral food challenges (OFCs), OIT, and adverse outcomes. Results: Fifty-two subjects under 24 months of age were initiated on OIT. Most subjects (84.6%) were on single food OIT, some (15.4%) were on multi-food OIT. No increased adverse outcomes were observed on multi-food OIT. Of the 59 initial OFCs, objective reactions occurred during 42 challenges, the majority being low grade reactions. During initial OFCs, 86.1% of peanut allergic children tolerated 1/8 of one Bamba stick with no reaction. The majority (73.1%) of subjects up-dosed at home and most (51.9%) had no reactions while up-dosing. Some had low grade cutaneous reactions, none requiring epinephrine or emergency evaluation. Conclusion: OIT in infants is safe and feasible to perform in a real-world setting using commercially available food products with at home up-dosing, thus increasing the availability of OIT for patients. https://doi.org/10.1016/j.jaip.2024.09.025
Brazil Nut (Bertholletia excelsa H.B.K.) Consumption in Energy-Restricted Intervention Decreases Proinflammatory Markers and Intestinal Permeability of Women with Overweight/Obesity: A Controlled Trial (Brazilian Nuts Study)
Background: Obesity is associated with low-grade inflammation and increased intestinal permeability (IP). The Brazil nut (BN) (Bertholletia excelsa H.B.K.) appears to be a promising dietary intervention to control inflammation by enhancing antioxidant defenses. Objectives: We aimed to assess the effect of daily BN consumption on inflammatory biomarkers and IP in the context of an energy-restricted intervention. Furthermore, we evaluated the correlation between the changes in these inflammatory markers and the changes in serum selenium and IP. Methods: In this 8-wk nonrandomized controlled trial, 56 women with overweight or obesity were allocated into 2 groups, both following an energy-restricted diet (-500 kcal/d). The control group (CO) consumed a nut-free diet, while the BN group consumed 8 g BN/d, providing 347.2 μg selenium (Se). Inflammatory cytokines were analyzed in plasma and Se in serum. IP was assessed using the lactulose/mannitol test (LM ratio). Results: Forty-six women completed the intervention. Both groups achieved similar energy restriction (CO Δ= -253.7 ± 169.4 kcal/d; BN Δ= -265.8 ± 141.8 kcal/d) and weight loss (CO Δ= -2.5 ± 0.5 kg; BN Δ= -3.5 ± 0.5 kg). The BN group showed lower values of C-reactive protein, tumor necrosis factor, interleukin (IL)1-β, IL-8, percentage lactulose excretion, and LM ratio than the CO group. Additionally, changes in serum Se concentration were predictive of changes in IL-8 concentration (β: -0.054; adjusted R2: 0.100; 95% confidence interval [CI]: -0.100; -0.007; P = 0.025), and changes in IL-8 were predictive of changes in the LM ratio (β: 0.006; adjusted R2: 0.101; 95% CI: 0.001, 0.011; P = 0.024). Conclusions: Regular intake of BNs can be a promising complementary dietary strategy for controlling low-grade inflammation and improving IP in women with overweight/obesity undergoing energy-restricted treatment. However, the effects of BNs seem to be Se status-dependent. This trial was registered at the Brazilian Registry of Clinical Trials (ReBEC: https://ensaiosclinicos.gov.br/rg/RBR-3ntxrm/). https://doi.org/10.1016/j.tjnut.2024.07.016
Prunes may blunt adverse effects of oral contraceptives on bone health in young adult women: a randomized clinical trial
Background: Oral contraceptives (OCs) may promote bone loss, thereby leading to suboptimal bone health later in life. Research is needed to determine whether dietary interventions can blunt OC-related bone loss; prune consumption, shown to be effective in improving bone density in previous studies, could provide a safe and inexpensive solution. Objectives: The purpose of this study was to determine whether 12 mo of consuming 50 g of prunes daily would prevent bone loss or increase bone accrual in young (18–25 y) OC users. Methods: Ninety women were randomly assigned to a control group not using OCs (non-OC), an OC group not consuming prunes (OC), and an OC group consuming 50 g prunes daily (OC+P) for 12 mo. Bone mineral density (BMD) was measured at baseline and after 12 mo via dual-energy X-ray absorptiometry (at all sites) and peripheral quantitative computed tomography (at tibia). Blood samples were collected at baseline and after 6 and 12 mo to assess biomarkers. Results: There were no significant differences between groups for dietary intake, physical activity, serum tartrate-resistant acid phosphatase-5b, or bone alkaline phosphatase concentrations. Baseline serum C-reactive protein and vitamin D concentrations were higher (P < 0.001) for OC and OC+P groups than those in the non-OC group. Serum parathyroid hormone was higher for non-OC group than OC group at both baseline (P = 0.049) and final (P = 0.032). BMD measured by dual-energy X-ray absorptiometry at all sites did not change among groups. Ultradistal radius BMD increased over time (P < 0.05) within non-OC and OC+P groups. Trabecular density of the distal tibia as measured by peripheral quantitative computed tomography decreased from baseline to 12 mo within the OC group only (P = 0.016). Conclusions: OC use tended to promote minor negative effects on bone and consuming prunes tended to provide a potential protective effect on trabecular density of the distal tibia and ultradistal radius. https://doi.org/10.1016/j.cdnut.2024.104417
Nut consumption, gut microbiota, and body fat distribution: results of a large, community-based population study
Objective: We aimed to investigate the relationships among nut consumption, gut microbiota, and body fat distribution. Methods: We studied 2255 Chinese adults in the Lanxi Cohort living in urban areas in Lanxi City, China. Fat distribution was assessed by dual-energy x-ray absorptiometry, and nut consumption was assessed using food frequency questionnaires. 16S ribosomal RNA (rRNA) sequencing was performed on stool samples from 1724 participants. Linear regression and Spearman correlation were used in all analyses. A validation study was performed using 1274 participants in the Lanxi Cohort living in rural areas. Results: Nut consumption was beneficially associated with regional fat accumulation. Gut microbial analysis suggested that a high intake of nuts was associated with greater microbial α diversity. Six genera were found to be associated with nut consumption, and the abundance of genera Anaerobutyricum, Anaerotaenia, and Fusobacterium was significantly associated with fat distribution. Favorable relationships between α diversity and fat distribution were also observed. Similar relationships between gut microbiota and fat distribution were obtained in the validation analysis. Conclusions: We have shown that nut consumption is beneficially associated with body fat distribution and gut microbiota diversity and taxonomy. Furthermore, the microbial features related to high nut intake are associated with a favorable pattern of fat distribution. https://doi.org/10.1002/oby.24099
Regulation of Intestinal Inflammation by Walnut-Derived Bioactive Compounds
Walnuts (Juglans regia L.) have shown promising effects in terms of ameliorating inflammatory bowel disease (IBD), attributed to their abundant bioactive compounds. This review comprehensively illustrates the key mechanisms underlying the therapeutic potential of walnuts in IBD management, including the modulation of intestinal mucosa permeability, the regulation of inflammatory pathways (such as NF-kB, COX/COX2, MAPCK/MAPK, and iNOS/NOS), relieving oxidative stress, and the modulation of gut microbiota. Furthermore, we highlight walnut-derived anti-inflammatory compounds, such as polyunsaturated fatty acids (PUFA; e.g., ω-3 PUFA), tocopherols, phytosterols, sphingolipids, phospholipids, phenolic compounds, flavonoids, and tannins. We also discuss unique anti-inflammatory compounds such as peptides and polysaccharides, including their extraction and preparation methods. Our review provides a theoretical foundation for dietary walnut supplementation in IBD management and provides guidance for academia and industry. In future, research should focus on the targeted isolation and purification of walnut-derived anti-inflammatory compounds or optimizing extraction methods to enhance their yields, thereby helping the food industry to develop dietary supplements or walnut-derived functional foods tailored for IBD patients. https://doi.org/10.3390/nu16162643
NUTS 2025 to Be Held at INC Headquarters
The meeting will bring together renowned health researchers from across the globe
After the success of NUTS 2022, another historic gathering of top health researchers is on the horizon. From October 9-10, 2025, the INC’s headquarters in Reus, Spain, will host NUTS 2025, a conference that will bring together some of the world’s top health researchers.
The aims of the NUTS 2025 conference are to summarize all the scientific evidence on the beneficial effects of nuts and dried fruit on health; to define new topics, needs and opportunities in research; to share knowledge with the food industry and set new primary objectives; and to prepare a white paper on the most important research developments for publication in a scientific journal.
The conference is being organized by Rovira i Virgili University and sponsored by the INC. Prof. Jordi Salas-Salvadó, Distinguished Professor of Nutrition at Rovira i Virgili University and Chairman of the INC World Forum for Nutrition Research and Dissemination, will serve as Chairman of the event. The Scientific Program Committee is chaired by Prof. Salas-Salvadó and also includes Prof. Joan Sabaté (Loma Linda, USA), Dr. Emilio Ros (Barcelona, Spain), Dr. Marta Guasch-Ferré (Copenhagen, Denmark) and Dr. Cyril Kendall (Toronto, Canada). The International Advisory Council consists of Prof. Cesarettin Alasalvar (Gebze, Türkiye), Dr. John Sievenpiper (Toronto, Canada), Prof. Penny Kris-Etherton (Pennsylvania, USA), Dr. Viswanathan Mohan (Chennai, India), Prof. Gang Liu (Wuhan, China) and Prof. Frank Hu (Boston, USA).
Further information about NUTS 2025 is available on the website.
Regular Intake of Brazil Nuts Shows Promise for Women With Overweight or Obesity
Eating Brazil nuts may control inflammation by enhancing antioxidant defenses
A new study published in the Journal of Nutrition assessed the effect of daily Brazil nut intake on inflammation and intestinal permeability in overweight and obese women following an energy-restricted diet.
In this non-randomized controlled trial, 56 women with overweight or obesity were allocated into one of two groups. Both groups followed an energy-restricted diet (−500 kcal/d) for eight weeks. The control group consumed a nut-free diet, while the Brazil nut group consumed 8 grams of Brazil nuts per day. Inflammatory cytokines were analyzed in plasma and intestinal permeability was assessed using the lactulose/mannitol ratio.
Both groups achieved similar weight loss. The Brazil nut group showed lower values of C-reactive protein, tumor necrosis factor, interleukin-1β, interleukin-8, percentage lactulose excretion, and lactulose/mannitol ratio than the control group.
The findings suggest that regular intake of Brazil nuts may be a promising complementary dietary strategy for controlling low-grade inflammation and improving intestinal permeability in overweight or obese women undergoing energy-restricted treatment.
Silveira, B. K. S., Silva, A. D., Rocha, D. M. U. P., Waskow, K., Martino, H. S. D., Bressan, J., & Hermsdorff, H. H. M. (2024). Brazil Nut (Bertholletia excelsa H.B.K.) Consumption in Energy-Restricted Intervention Decreases Proinflammatory Markers and Intestinal Permeability of Women with Overweight/Obesity: A Controlled Trial (Brazilian Nuts Study). The Journal of Nutrition, 154(9), 2670–2679.