Archive

Research Area: Cardiovascular Health

Pecans and human health: distinctive benefits of an American nut.

Sandhu, A.K., I. Edirisinghe, B. Burton-Freeman, 2025. Pecans and human health: distinctive benefits of an American nut. Nutrients. 17, 3686. https://doi.org/10.3390/nu17233686

Pecans are a tree nut native to America with a rich content of unsaturated fatty acids, minerals, fiber, and a diverse array of bioactive components, including polyphenols, tocopherols, and phytosterols. This review summarizes variations in the phenolic composition of pecans from various parts of the world based on cultivar, maturity stage, postharvest storage, and processing. Additionally, the review delves into the bio-accessibility and bioavailability of bioactive components from pecans and their potential influence on diet quality, body weight, satiety, cardiometabolic, brain and gut health. Data from human clinical trials suggest that replacing foods/snacks with pecans improves overall diet quality and lipid profiles. However, inconsistent effects are observed on vascular function, glycemia, and inflammation. Body weight changes after pecan intake are reported as neutral, with promising results on satiety peptides and appetite regulation. Cognition and gut health are emerging areas of research with very limited data from both human and preclinical models, warranting further investigation. Overall, the current literature supports the cardiometabolic benefits of pecans within healthy dietary patterns. Future research should focus on well-controlled studies targeting at-risk populations to understand mechanistic endpoints such as metabolomics, microbiome, and vascular function assessments to substantiate the role of pecans in dietary guidance.

Effect of premeal pistachio supplementation on cardiometabolic risk factors among Asian Indian adults with prediabetes: A randomized controlled trial.

Ashwini, K., K. Abirami, R. Gayathri, S. Sasikala, V. Sudha, S. Shobana, R.G. Jeevan, K. Krishnaswamy, V. Deepika, M. Rajalakshmi, R.M.R. Bai, K. Parkavi, S. Padmavathi, R.M. Anjana, R. Unnikrishnan, F.B. Hu, W.C. Willett, J. Salas-Salvadó, S.N. Bhupathiraju, V. Mohan, 2025. Effect of premeal pistachio supplementation on cardiometabolic risk factors among Asian Indian adults with prediabetes: A randomized controlled trial. J Nutr. 155(3):899-909. https://doi.org/10.1016/j.tjnut.2024.12.005

Background: Asian Indians are susceptible to developing type 2 diabetes at a lower age and often consume diets that are high in glycemic load and low in healthy fats. Objectives: This study aimed to evaluate the effect of 30g prebreakfast and 30g predinner supplementation of pistachios for 12 wk on glycated hemoglobin (HbA1c), other glycemic markers, anthropometry, and lipid profile of Asian Indians with prediabetes. Methods: In a 12-wk parallel arm, randomized controlled trial, we recruited 120 participants with prediabetes based on American Diabetes Association criteria. The intervention group (n = 60) consumed 60g pistachios (30g prebreakfast and predinner) whereas the control group (n = 60) followed a routine diet that excluded nuts. At baseline and 12 wk, we collected blood samples for biochemical analysis, anthropometrics, and 24-h recalls. Participants wore a continuous glucose monitoring (CGM) sensor during the trial’s first and last 2 wk. Urinary N-methyl-trans-4-hydroxy-l-proline (MHP) was measured as a marker of pistachio consumption. Results: A total of 109 participants completed the study (follow-up rate = 90.8%). Compared with participants in the control group, those in the intervention group had significant reductions in HbA1c (mean between-group difference: −0.2; 95% confidence interval: −0.3, −0.1; P < 0.001] with no significant changes in fasting or 2-h post glucose load plasma glucose. Compared with the control group, the intervention group had significant reductions in serum triglyceride, waist circumference, lipid accumulation product, visceral adiposity index, and atherogenic index. Urinary MHP (mg/g creatinine) showed a 62% increase in the intervention compared with the control group (P < 0.05). CGM data revealed significant decreases in the incremental area under the curve, 2-h after breakfast (28%, p=0.01) and after dinner (17%, P = 0.002) in the intervention group compared to the control group. Conclusions: A 12-wk, premeal load of 60g pistachios lowers HbA1c and improves cardiometabolic profile among Asian Indians with prediabetes. This is among the first studies to investigate these effects in this ethnic group.

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.

Consuming pecans as a snack improves lipids/lipoproteins and diet quality compared with usual diet in adults at increased risk of cardiometabolic diseases: a randomized controlled trial.

Hart, T.L., P.M. Kris-Etherton, K.S. Petersen, 2025. Consuming pecans as a snack improves lipids/lipoproteins and diet quality compared with usual diet in adults at increased risk of cardiometabolic diseases: a randomized controlled trial. Amer J Clin Nutr. ISSN 0002-9165,doi.org/10.1016/j.ajcnut.2025.01.024.

Background: The vascular and cardiometabolic effects of pecans are relatively understudied. Objectives: The aim was to examine how substitution of usual snack foods with 57g/d of pecans affects vascular health, risk factors for cardiometabolic diseases, and diet quality, compared with continuing usual intake in individuals at risk of cardiometabolic diseases. Methods: A 12-wk single-blinded, parallel, randomized controlled trial was conducted. Adults with ≥1 criterion for metabolic syndrome who were free from cardiovascular disease and type 2 diabetes were included. Participants were provided with 57g/d of pecans and instructed to replace the snacks usually consumed with the provided pecans. The control group was instructed to continue consuming their usual diet. Flow-mediated dilation (FMD),primary outcome, along with blood pressure, carotid-femoral pulse wave velocity (cf-PWV), lipids/lipoproteins, and glycemic control were measured at baseline and following the intervention. Participants completed 3 24-h recalls at 3 time points (baseline, week 6, and week 12) during the study (9 recalls in total). The Healthy Eating Index-2020 (HEI-2020) was calculated to assess diet quality. Results: In total, 138 participants (mean ± SD; 46 ± 13 y, 29.8 ± 3.7 kg/m2) were randomly assigned (69 per group). No between-group differences in FMD, cf-PWV, or blood pressure were observed. Compared with the usual diet group, pecan intake reduced total cholesterol (− 8.1 mg/dL; 95% confidence interval [CI]: −14.5, −1.7), LDL cholesterol ( −7.2 mg/dL; 95% CI −12.3, −2.1), non-HDL-cholesterol (− 9.5 mg/dL; 95% CI −15.3, −3.7), and triglycerides concentrations ( −16.4 mg/dL; 95% CI −30.0, −2.9). Weight tended to increase in the pecan group compared with the usual diet group (0.7 kg; 95% CI −0.1, 1.4). The HEI-2020 increased by 9.4 points (95% CI 5.0, 13.7) in the pecan group compared with the usual diet group. Conclusions: Replacing usual snacks with 57 g/d of pecans for 12-wk improves lipids/lipoproteins and diet quality but does not affect vascular health in adults at risk of cardiometabolic disease.