Archive

Research Area: Metabolic Syndrome

Effects of supplementing the usual diet with a daily dose of walnuts for two years on metabolic syndrome and its components in an elderly cohort.

Al Abdrabalnabi, A., S. Rajaram, E. Bitok, K. Oda, W.L. Beeson, A. Kaur, M. Cofán, M. Serra-Mir, I. Roth, E. Ros, J. Sabaté, 2020. Effects of supplementing the usual diet with a daily dose of walnuts for two years on metabolic syndrome and its components in an elderly cohort. Nutrients. 11;12(2). pii: E451. doi: 10.3390/nu12020451.

Accumulating evidence links nut consumption with an improved risk of metabolic syndrome (MetS); however, long-term trials are lacking. We examined the effects of a daily dose of walnuts for two years on MetS in a large elderly cohort. A total of 698 healthy elderly participants were randomly assigned to either a walnut supplemented or a control diet. The participants in the walnut group were provided with packaged walnuts (1, 1.5, or 2 oz. or ~15% of energy) and asked to incorporate them into their daily habitual diet. The participants in the control group were asked to continue with their habitual diet and abstain from eating walnuts and other tree nuts. Intake of n-3 fatty acid supplements was not permitted in either group. Fasting blood chemistries, blood pressure, and anthropometric measurements were obtained at baseline and at the end of intervention. A total of 625 participants (67% women, mean age 69.1 y) completed this two-year study (90% retention rate). Triglycerides decreased in both walnut (-.94 mg/dl) and control (-0.96 mg/dl) groups, with no significant between-group differences. There was a non-significant decrease in systolic and diastolic blood pressure in the walnut group (-1.30 and -0.71 mm Hg, respectively) and no change in the control group. Fasting blood glucose decreased by ~1 point in both the walnut and control groups. There were no significant between-group differences in the development or reversion of MetS. In conclusion, supplementing the diet of older adults with a daily dose of walnuts had no effect on MetS status or any of its components, although the walnut group tended to have lower blood pressure.

Metabolic syndrome features and excess weight were inversely associated with nut consumption after 1-year follow-up in the PREDIMED-Plus study.

Julibert, A., M. del Mar Bibiloni, L. Gallardo-Alfaro, M. Abbate, M.Á. Martínez-González, J. Salas-Salvadó, D. Corella, M. Fitó, J.A. Martínez, Á.M. Alonso-Gómez, J. Wärnberg, J. Vioque, D. Romaguera, J. Lopez-Miranda, R. Estruch, F.J. Tinahones, J. Lapetra, L. Serra-Majem, N. Cano-Ibañez, V. Martín-Sánchez, X. Pintó, J.J. Gaforio, P. Matía-Martín, J. Vidal, C. Vázquez, L. Daimiel, E. Ros, C. Sayon-Orea, N. Becerra-Tomás, I.M. Gimenez-Alba, O. Castañer, I. Abete, L. Tojal-Sierra, J. Pérez-López, L. Notario-Barandiaran, A. Colom, A. Garcia-Rios, S. Castro-Barquero, R. Bernal, J.M. Santos-Lozano, C.I. Fernández-Lázaro, P. Hernández-Alonso, C. Saiz, M.D. Zomeño, M.A. Zulet, M.C. Belló-Mora, J. Basterra-Gortari, S. Canudas, A. Goday, J.A. Tur, PREDIMED-PLUS investigators, 2020. Metabolic syndrome features and excess weight were inversely associated with nut consumption after 1-year follow-up in the PREDIMED-Plus study. J Nutr. 00:1–10.

Background: High nut consumption has been previously associated with decreased prevalence of metabolic syndrome (MetS) regardless of race and dietary patterns. Objectives: The aim of this study was to assess whether changes in nut consumption over a 1-y follow-up are associated with changes in features of MetS in a middle-aged and older Spanish population at high cardiovascular disease risk. Methods: This prospective 1-y follow-up cohort study, conducted in the framework of the PREvención con DIeta MEDiterránea (PREDIMED)-Plus randomized trial, included 5800 men and women (55-75 y old) with overweight/obesity [BMI (in kg/m2) ≥27 and <40] and MetS. Nut consumption (almonds, pistachios, walnuts, and other nuts) was assessed using data from a validated FFQ. The primary outcome was the change from baseline to 1 y in features of MetS [waist circumference (WC), glycemia, HDL cholesterol, triglyceride (TG), and systolic and diastolic blood pressure] and excess weight (body weight and BMI) according to tertiles of change in nut consumption. Secondary outcomes included changes in dietary and lifestyle characteristics. A generalized linear model was used to compare 1-y changes in features of MetS, weight, dietary intakes, and lifestyle characteristics across tertiles of change in nut consumption. Results: As nut consumption increased, between each tertile there was a significant decrease in WC, TG, systolic blood pressure, weight, and BMI (P < 0.05), and a significant increase in HDL cholesterol (only in women, P = 0.044). The interaction effect between time and group was significant for total energy intake (P < 0.001), adherence to the Mediterranean diet (MedDiet) (P < 0.001), and nut consumption (P < 0.001). Across tertiles of increasing nut consumption there was a significant increase in extra virgin olive oil intake and adherence to the MedDiet; change in energy intake, on the other hand, was inversely related to consumption of nuts. Conclusions: Features of MetS and excess weight were inversely associated with nut consumption after a 1-y follow-up in the PREDIMED-Plus study cohort. This trial was registered at isrctn.com as ISRCTN89898870.

Health benefits of pistachios consumption.

Terzo, S., S. Baldassano, G.F. Caldara, V. Ferrantelli, G. Lo Dico, F. Mulè, A. Amato, 2019. Health benefits of pistachios consumption. Nat Prod Res. 33(5):715-726.

The health benefits of nuts, mainly in relation to the improvement of dysmetabolic conditions such as obesity, type 2 diabetes mellitus and the related cardiovascular diseases, have been widely demonstrated. Compared to other nuts, pistachios have a lower fat and caloric content, and contain the highest levels of unsaturated fatty acids, potassium, γ-tocopherol, phytosterols and xanthophyll carotenoids, all substances that are well known for their antioxidant and anti-inflammatory actions. This variety of nutrients contributes to the growing body of evidence that the consumption of pistachios improves health, leading to a greater potential of healthy antioxidant and anti-inflammatory activity, glycemic control, and endothelial function. The present review examines the nutrients and phytochemicals present in pistachios as well as the potential health benefits of including pistachios in a diet.

Identification of plasma lipid metabolites associated with nut consumption in US men and women.

Malik, V.S., M. Guasch-Ferre, F.B. Hu, M.K. Townsend, O.A. Zeleznik, A.H. Eliassen, S.S. Tworoger, E.W. Karlson, K.H. Costenbader, A. Ascherio, K.M. Wilson, L.A. Mucci, E.L. Giovannucci, C.S. Fuchs, Y. Bao, 2019. Identification of plasma lipid metabolites associated with nut consumption in US men and women. J Nutr 149:1215–1221.

BACKGROUND: Intake of nuts has been inversely associated with risk of type 2 diabetes and cardiovascular disease, partly through inducing a healthy lipid profile. How nut intake may affect lipid metabolites remains unclear. OBJECTIVE: The aim of this study was to identify the plasma lipid metabolites associated with habitual nut consumption in US men and women. METHODS: We analyzed cross-sectional data from 1099 participants in the Nurses’ Health Study (NHS), NHS II, and Health Professionals Follow-up Study. Metabolic profiling was conducted on plasma by LC-mass spectrometry. Nut intake was estimated from food-frequency questionnaires. We included 144 known lipid metabolites that had CVs ≤25%. Multivariate linear regression was used to assess the associations of nut consumption with individual plasma lipid metabolites. RESULTS: We identified 17 lipid metabolites that were significantly associated with nut intake, based on a 1 serving (28 g)/d increment in multivariate models [false discovery rate (FDR) P value <0.05]. Among these species, 8 were positively associated with nut intake [C24:0 sphingomyelin (SM), C36:3 phosphatidylcholine (PC) plasmalogen-A, C36:2 PC plasmalogen, C24:0 ceramide, C36:1 PC plasmalogen, C22:0 SM, C34:1 PC plasmalogen, and C36:2 phosphatidylethanolamine plasmalogen], with changes in relative metabolite level (expressed in number of SDs on the log scale) ranging from 0.36 to 0.46 for 1 serving/d of nuts. The other 9 metabolites were inversely associated with nut intake with changes in relative metabolite level ranging from -0.34 to -0.44. In stratified analysis, 3 metabolites were positively associated with both peanuts and peanut butter (C24:0 SM, C24:0 ceramide, and C22:0 SM), whereas 6 metabolites were inversely associated with other nuts (FDR P value <0.05). CONCLUSIONS: A panel of lipid metabolites was associated with intake of nuts, which may provide insight into biological mechanisms underlying associations between nuts and cardiometabolic health. Metabolites that were positively associated with intake of nuts may be helpful in identifying potential biomarkers of nut intake.

Daily walnut intake improves metabolic syndrome status and increases circulating adiponectin levels: randomized controlled crossover trial.

Hwang, H.J., Y. Liu, H.S. Kim, H. Lee, Y. Lim, H. Park, 2019. Daily walnut intake improves metabolic syndrome status and increases circulating adiponectin levels: randomized controlled crossover trial. Nutr Res Pract. 13(2):105–114.

Background/Objectives: Several previous studies have investigated whether regular walnut consumption positively changes heart-health-related parameters. The aim of this study was to investigate the effects of daily walnut intake on metabolic syndrome (MetS) status and other metabolic parameters among subjects with MetS. Materials/Methods: This study was a two-arm, randomized, controlled crossover study with 16 weeks of each intervention (45 g of walnuts or iso-caloric white bread) with a 6-week washout period between interventions. Korean adults with MetS (n = 119) were randomly assigned to one of two sequences; 84 subjects completed the trial. At each clinic visit (at 0, 16, 22, and 38 weeks), MetS components, metabolic parameters including lipid profile, hemoglobin A1c (HbA1c), adiponectin, leptin, and apolipoprotein B, as well as anthropometric and bioimpedance data were obtained. Results: Daily walnut consumption for 16 weeks improved MetS status, resulting in 28.6%-52.8% reversion rates for individual MetS components and 51.2% of participants with MetS at baseline reverted to a normal status after the walnut intervention. Significant improvements after walnut intake, compared to control intervention, in high-density lipoprotein cholesterol (HDL-C) (P = 0.028), fasting glucose (P = 0.013), HbA1c (P = 0.021), and adiponectin (P = 0.019) were observed after adjustment for gender, age, body mass index, and sequence using a linear mixed model. Conclusion: A dietary supplement of 45 g of walnuts for 16 weeks favorably changed MetS status by increasing the concentration of HDL-C and decreasing fasting glucose level. Furthermore, consuming walnuts on a daily basis changed HbA1c and circulating adiponectin levels among the subjects with MetS.

Effects of almond consumption on metabolic and liver function in overweight and obese adults with elevated fasting blood glucose: A randomized controlled trial.

Bowen, J., N.D. Luscombe-Marsh, W. Stonehouse, C. Tran, G.B. Rogers, N. Johnson, C.H. Thompson, G.D. Brinkworth, 2019. Effects of almond consumption on metabolic and liver function in overweight and obese adults with elevated fasting blood glucose: A randomized controlled trial. Clin. Nutr. ESPEN 30:10-18.

Background: Almonds are a rich source of bioactive components. This study examined the effects of daily almond consumption on glycaemic regulation, liver fat concentration and function, adiposity, systemic inflammation and cardiometabolic health. Methods: 76 adults with elevated risk of type 2 diabetes (T2D) or T2D (age: 60.7 ± 7.7 years, body mass index: 33.8 ± 5.6 kg/m2) were randomly assigned to daily consumption of either 2 servings of almonds (AS:56 g/day) or an isocaloric, higher carbohydrate biscuit snack (BS) for 8 weeks. Glycosylated haemoglobin (HbA1c), glycaemic variability (GV), liver fat, serum aminotransferases, body weight and composition, markers of cardio-metabolic risk and systemic inflammation were assessed at baseline and week 8. Results: No group differential effects were observed on HbA1c, GV, body weight and composition, liver fat and aminotransferases, cardio-metabolic health and inflammatory markers (all P > 0.05). For serum TC/HDL-C ratio a significant gender × treatment × time interaction occurred (P < 0.01), such that in women TC/HDL-C ratio was significantly reduced after AS compared to BS (-0.36 [0.26] mmol/L [n = 14] vs. -0.14 [0.32] mmol/L [n = 17]; P = 0.05), but not in men (P = 0.52). Conclusions: Compared to BS, AS consumed between meals did not substantially alter glycaemic regulation, liver fat or function, adiposity, and metabolic health and inflammatory markers. Serum TC/HDL-C ratio improved in women, but not in men with AS; but as this sub-analysis was not defined a priori the results should be interpreted with caution. Further research should examine the longer-term health effects of regular almond consumption and differential gender responses.

Lipid lowering effect of almonds (Prunus Dulcis) in healthy adults.

Tahir, F.N., M. Danyal, S.I.A. Shah, J.A. Qureshi, 2019. Lipid lowering effect of almonds (Prunus Dulcis) in healthy adults. Pakistan Journal of Medical and Health Sciences. 12(4):1356-1358.

Background: Almonds (Prunus dulcis) are low in saturated fats and cholesterol and high in unsaturated fatty acids. Almonds also contain high concentrations of other nutrients like vitamin E, plant sterols, phytochemicals and dietary fibers. Almonds are associated with a reduced risk of cardiovascular disorders (CVD) by having a potentially beneficial impact of on serum lipids due to their nutrient composition. Aim: To investigate the effect of regular almond consumption on the serum lipid profile of normolipidemic adults. Methods: In this non-randomized prospective study, 19 normolipidemic adults (10 males, 9 females) with an age range from 21 to 60 years consumed 50 grams of raw almonds for 30 days. Fasting blood samples were collected from each participant at baseline and on the 31st day for lipid profile analysis. Results: Marked decreases in serum total cholesterol level (p-value= 0.000) and serum low-density lipoprotein (LDL) level (p-value= 0.047) were observed from baseline values following almond treatment for a month. An increase in high density lipoprotein (HDL) level was also seen but it was not statistically significant (p-value=0.081). Conclusion: Regular intake of almonds can help maintain a normal lipid profile in healthy adults and reduce the risk of CVD. Almond consumption should be encouraged in the local healthy population for improved metabolic and cardiovascular health outcomes.

The association between metabolic syndrome and peanuts, pine nuts, almonds consumption: The Ansan and Ansung Study.

Jung, J.Y., S.K. Park, C.-M. Oh, J.-M. Choi, J.-H. Ryoo, J. Kim, M.K. Kim, 2019. The association between metabolic syndrome and peanuts, pine nuts, almonds consumption: The Ansan and Ansung Study. Endocrine. 65(2):270-277.

Background: Previous studies reported an inverted relationship between nut consumption and the incidence of metabolic syndrome (MetS). The present study investigated the incidental risk for MetS according to peanut, almond, and fine nut consumption in the Korean population. Methods: In a community-based Korean cohort, 5306 Korean adults were divided into four groups according to their peanut, almond, and pine nut intake (<1/month, 1/month-0.5/week, 0.5-1/week, and ≥1/week, in which one serving = 15 g) and were followed-up for 10 years. A Cox proportional hazard model was used to evaluate the hazard ratios (HRs) with confidence intervals (CI) for MetS in each study group. Age subgroup (≥50 or <50 years) analysis was also conducted. Results: The age and multivariable-adjusted HRs with 95% CIs for MetS showed a significant inverse dose-response relationship between peanut, almond, and pine nut intake and the incidence of MetS in men and women (multivariable-adjusted HRs [95% CI] in men; 0.91 [0.76-1.09] in 1/month-0.5/week, 1.03 [0.80-1.31] in 0.5-1/week, 0.72 [0.56-0.93] in ≥1/week and in women; 0.81 [0.65-1.003] in 1/month-0.5/week, 0.76 [0.54-1.07] in 0.5-1/week, 0.57 [0.41-0.79] ≥1/week)). Subgroup analysis showed a significant difference in middle-aged men (≥1/week) and old-aged women (≥0.5/week). Conclusion: The results of the present study suggested that peanut, almond, and pine nut intake (≥15 g/week) may be inversely related to incidence risk of MetS in the Korean general population. Additionally, the association between nut consumption and MetS incidence risk may differ in sex and age subgroups.

The effect of nuts on markers of glycemic control: a systematic review and meta-analysis of randomized controlled trials.

Tindall, A.M., E.A. Johnston, P.M. Kris-Etherton, K.S. Petersen, 2019. The effect of nuts on markers of glycemic control: a systematic review and meta-analysis of randomized controlled trials. Am J Clin Nutr. 109:297–314.

Background: Observational evidence suggests higher nut consumption is associated with better glycemic control; however, it is unclear if this association is causal. Objectives: We aimed to conduct a systematic review and meta-analysis of randomized controlled trials to examine the effect of tree nuts and peanuts on markers of glycemic control in adults. Methods: A systematic review and meta-analysis of randomized controlled trials was conducted. A total of 1063 potentially eligible articles were screened in duplicate. From these articles, 40 were eligible for inclusion and data from these articles were extracted in duplicate. The weighted mean difference (WMD) between the nut intervention and control arms was determined for fasting glucose, fasting insulin, glycated hemoglobin (HbA1c), and homeostasis model assessment of insulin resistance (HOMA-IR) using the DerSimonian and Laird random-effects method. For outcomes where a limited number of studies were published, a qualitative synthesis was presented. Results: A total of 40 randomized controlled trials including 2832 unique participants, with a median duration of 3 mo (range: 1–12 mo), were included. Overall consumption of tree nuts or peanuts had a favorable effect on HOMA-IR (WMD: −0.23; 95% CI: −0.40, −0.06; I2=51.7%) and fasting insulin (WMD: −0.40μIU/mL;95% CI: −0.73, −0.07μ IU/mL; I2 = 49.4%). There was no significant effect of nut consumption on fasting blood glucose (WMD: −0.52 mg/dL;95% CI: −1.43,0.38mg/dL; I2 =53.4%) o rHbA1c (WMD: 0.02%; 95% CI: −0.01%, 0.04%; I2 =51.0%). Conclusions: Consumption of peanuts or tree nuts significantly decreased HOMA-IR and fasting insulin; there was no effect of nut consumption on HbA1c or fasting glucose. The results suggest that nut consumption may improve insulin sensitivity. In the future, well-designed clinical trials are required to elucidate the mechanisms that account for these observed effects.

A pecan-rich diet improves cardiometabolic risk factors in overweight and obese adults: A randomized controlled trial.

McKay, D.L., M. Eliasziw, C.Y.O. Chen, J.B. Blumberg, 2018. A pecan-rich diet improves cardiometabolic risk factors in overweight and obese adults: A randomized controlled trial. Nutrients. 2018, 10, 339; doi:10.3390/nu10030339.

Evidence from observational and intervention studies has shown a high intake of tree nuts is associated with a reduced risk of cardiovascular disease (CVD), mortality from type 2 diabetes (T2DM), and all-cause mortality. However, there is limited data regarding their effects on indicators of cardiometabolic risk other than hypercholesterolemia, and little is known about the demonstrable health benefits of pecans (Carya illinoensis (Wangenh.) K.Koch). We conducted a randomized, controlled feeding trial to compare the effects of a pecan-rich diet with an isocaloric control diet similar in total fat and fiber content, but absent nuts, on biomarkers related to CVD and T2DM risk in healthy middle-aged and older adults who are overweight or obese with central adiposity. After 4 weeks on a pecan-rich diet, changes in serum insulin, insulin resistance (HOMA-IR) and beta cell function (HOMA-β) were significantly greater than after the control diet (p < 0.05). Pecan consumption also lowered the risk of cardiometabolic disease as indicated by a composite score reflecting changes in clinically relevant markers. Thus, compared to the control diet, the pecan intervention had a concurrent and clinically significant effect on several relevant markers of cardiometabolic risk.