Archive

Research Area: Metabolic Syndrome

Consuming tree nuts daily as between-meal snacks reduces food cravings and improves diet quality in American young adults at high metabolic syndrome risk.

Lillegard, K., A. Widmer, J.R. Koethe, H.J. Silver, 2025. Consuming tree nuts daily as between-meal snacks reduces food cravings and improves diet quality in American young adults at high metabolic syndrome risk. Nutrients. 17, 3778. https://doi.org/10.3390/nu17233778.

Background: Daily energy intake from snacking behaviors has increased over the past few decades, during which the prevalence of obesity and metabolic syndrome has risen to epidemic proportions. There remains considerable room for improvement in the overall quality of dietary intakes of the U.S. population when compared to national recommendations. Food cravings may contribute to the types of snacks chosen for consumption, and thus, the frequency of foods and food groups consumed, and the overall nutritional quality of the diet. Methods: Eighty-four young (28.5 ± 4.3 years) adults with at least one metabolic syndrome risk factor participated in a parallel-arm single-blind randomized trial designed to compare effects of consuming a mix of tree nuts versus typical high-carbohydrate food items as between-meal snacks for 16 weeks. Cravings for 28 common foods via the Food Craving Inventory, short-term dietary intakes via 24 h multi-pass methodology, food group frequency via the Rapid Eating Assessment for Participants, usual hunger and fullness via visual analog scales, appetite-regulating hormones, and diet quality via the Healthy Eating Index-2015 were measured at baseline and end of study. Results: Participants in the TNsnack group had significant decreases in cravings for high sweet items and fast-food items, which were associated with decreased frequency of desserts and salty foods along with increased intake of higher protein items. In contrast, no significant reductions in food cravings or preference for sweets were observed in the CHOsnack group. Decreased cravings for sweets by TNsnack participants were associated with increased total GLP-1 levels: cake (r = −0.35, p = 0.03), brownies (r = −0.44, p = 0.02), candy (r = −0.36, p = 0.03) and ice cream (r = −0.33, p = 0.04). Overall, the total diet quality score improved by 19% among TNsnack participants. Conclusions: Replacing more typical between-meal snacks with tree nuts may reduce food cravings, particularly for sweeter food items that are likely to be nutrient poor and energy dense. By reducing cravings and frequency of intake, consuming tree nuts as snacks could facilitate having a higher quality, more nutrient-dense diet and mitigate potential negative effects of snacking on metabolic health in young adults.

Association between nut consumption and metabolic syndrome in Korean adults.

Shin, S., 2025. Association between nut consumption and metabolic syndrome in Korean adults. J Lipid Atheroscler. 14(2):219-228. https://doi.org/10.12997/jla.2025.14.2.219

Objective: Although nuts have been reported to lower the risk of multiple diseases, evidence regarding their effect on metabolic syndrome (MetS) in Asian populations is limited. Therefore, this study aimed to clarify the association between nut consumption and the risk of MetS. Methods: A cross-sectional analysis was conducted using data from the seventh Korea National Health and Nutrition Examination Survey (2016–2018). MetS was defined according to the guidelines of the National Cholesterol Education Program Adult Treatment Panel III. Responses to a single 24-hour dietary recall from 4,365 younger adults (19–39 years), 7,498 middle-aged adults (40–64 years), and 4,378 older adults (≥65 years) were analyzed using multivariable logistic regression models. Results: In this study, based on the culinary definition, nuts included tree nuts and peanuts. Approximately 25% of Korean adults were found to consume nuts. After adjusting for confounding variables, including age, body mass index, total energy intake, household income, alcohol consumption, smoking, aerobic exercise, and energy from carbohydrates, nut consumption was associated with a lower risk of MetS among middle-aged men (40–64 years; odds ratio [OR], 0.68; 95% confidence interval [CI], 0.53–0.88), older men (≥65 years; OR, 0.72; 95% CI, 0.53–0.98), and older women (≥65 years; OR, 0.69; 95% CI, 0.53–0.89). Conclusion: These results suggest that consuming nuts may exert protective effects against MetS in middle-aged Korean men and older Korean adults.

Novel proteomic signatures may indicate MRI-assessed intrahepatic fat state and changes: The DIRECT PLUS clinical trial.

Goldberg, D.T., A. Yaskolka Meir, G. Tsaban, E. Rinott, A. Kaplan, H. Zelicha, N. Klöting, U. Ceglarek, B. Iserman, I. Shelef, P. Rosen, M. Blüher, M. Stumvoll, O. Etzion, M.J. Stampfer, F.B. Hu, I. Shai, 2025. Novel proteomic signatures may indicate MRI-assessed intrahepatic fat state and changes: The DIRECT PLUS clinical trial. Hepatology. 81(1):198-211.   

Background and aims: We demonstrated in the randomized 18-month DIRECT PLUS trial (n = 294) that a Mediterranean (MED) diet, supplemented with polyphenol-rich Mankai duckweed, green tea, and walnuts and restricted in red/processed meat, caused substantial intrahepatic fat (IHF%) loss compared with 2 other healthy diets, reducing NAFLD by half, regardless of similar weight loss. Here, we investigated the baseline proteomic profile associated with IHF% and the changes in proteomics associated with IHF% changes induced by lifestyle intervention. Approach and results: We calculated IHF% by proton magnetic resonance spectroscopy (normal IHF% <5% and abnormal IHF% ≥5%). We assayed baseline and 18-month samples for 95 proteomic biomarkers. Participants (age = 51.3 ± 10.8 y; 89% men; and body mass index = 31.3 ± 3.9 kg/m 2) had an 89.8% 18-month retention rate; 83% had eligible follow-up proteomics measurements, and 78% had follow-up proton magnetic resonance spectroscopy. At baseline, 39 candidate proteins were significantly associated with IHF% (false discovery rate <0.05), mostly related to immune function pathways (e.g., hydroxy acid oxidase 1). An IHF% prediction based on the DIRECT PLUS by combined model (R2 = 0.47, root mean square error = 1.05) successfully predicted IHF% (R2 = 0.53) during testing and was stronger than separately inputting proteins/traditional markers (R2 = 0.43/0.44). The 18-month lifestyle intervention induced changes in 18 of the 39 candidate proteins, which were significantly associated with IHF% change, with proteins related to metabolism, extracellular matrix remodeling, and immune function pathways. Thrombospondin-2 protein change was higher in the green-MED compared to the MED group, beyond weight and IHF% loss (p = 0.01). Protein principal component analysis revealed differences in the third principal component time distinct interactions across abnormal/normal IHF% trajectory combinations; (p < 0.05 for all). Conclusions: Our findings suggest novel proteomic signatures that may indicate MRI-assessed IHF state and changes during lifestyle intervention. Specifically, carbonic anhydrase 5A, hydroxy acid oxidase 1, and thrombospondin-2 protein changes are independently associated with IHF% change, and thrombospondin-2 protein change is greater in the green-MED/high polyphenols diet.

Consumption of tree nuts as snacks stimulates changes in plasma fatty acid profiles and adipose tissue gene expression in young adults at risk for metabolic syndrome

Widmer, A., K. Lillegard, K. Wood, M. Robles, R. Fan, F. Ye, J.R. Koethe, H.J. Silver, 2025. Consumption of tree nuts as snacks stimulates changes in plasma fatty acid profiles and adipose tissue gene expression in young adults at risk for metabolic syndrome. Clinical Nutrition. (48)25 – 34. https://doi.org/10.1016/j.clnu.2025.03.002.

Background and aims: The prevalence of metabolic syndrome has been increasing in young adults, concomitant with the occurrence of increased abdominal adiposity. We previously reported that consuming tree nuts, as replacement for typical high-carbohydrate snacks, reduces visceral fat and waist circumference in young adults who have one or more metabolic syndrome risk factors. We aimed to investigate the effects of tree nuts snack consumption on plasma and adipose tissue fatty acid profiles along with changes in the expression of adipose tissue genes involved in thermogenesis, glycemia, adipocyte signaling, lipolysis, and immunity. Methods: A randomized parallel-arm 16-week intervention trial was conducted in 84 adults aged 22-36 years. Participants in both groups were provided with caloric goals for weight maintenance, daily menus, and pre-portioned snacks at every other week visits with study registered dietitians. Changes in dietary fatty acid intakes, plasma and abdominal subcutaneous adipose tissue (SAT) triglycerides fatty acid profiles using gas-liquid chromatography, and the expression of 241 genes in abdominal SAT were evaluated. Results: Consuming tree nuts snacks increased mono- and polyunsaturated fatty acid intakes yielding a 9-fold greater dietary unsaturated to saturated fat ratio. The tree nuts snack group also had significantly greater improvements in plasma 16:1/16:0 ratio; plasma phospholipids oleic and gamma linolenic acid content; plasma diglycerides, triglycerides, and cholesterol esters oleic acid content; and total plasma monounsaturated fatty acids. While abdominal SAT only showed trends for increased oleic acid content and unsaturated to saturated fat ratio, the tree nuts snacks participants had altered expression of 13 genes in abdominal SAT that have roles in nutrient sensing, energy homeostasis, and vulnerability to obesity. Conclusions: Replacing typical high-carbohydrate snacks with tree nuts results in more favorable dietary, plasma, and adipose tissue fatty acid profiles that could aid in preventing the development of excess adiposity and cardiometabolic disease states including metabolic syndrome.