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Research Area: Cardiovascular Health

The effect of almonds consumption on blood pressure: A systematic review and dose-response meta-analysis of randomized control trials.

Li, Z., A.S. Bhagavathula, M. Batavia, C. Clark, H.M. Abdulazeem, J. Rahmani, F. Yin, 2020. The effect of almonds consumption on blood pressure: A systematic review and dose-response meta-analysis of randomized control trials. 32(2):1757-1763.

Almond is rich in antioxidants and phytochemicals such as methylquercetin, protocatechuic acid, catechin, flavonoids, p-hydroxybenzoic acid, resveratrol, vanillic acid, and kaempferol. The aim of the present study was to systematically review and dose-response meta-analyses the effects of almond consumption on systolic and diastolic blood pressure (SBP/DBP), respectively, in Randomized Controlled Trials (RCTs). A systematic search was performed in PubMed/MEDLINE, web of sciences and SCOPUS by 2 researchers, independently to identify randomised controlled trials up to July 2019. There were no time or language restrictions. PRISMA guidelines were followed in conducting this meta-analysis. Fifteen studies with 21 arms, containing 853 participants, reported SBP as an outcome measure. Pooled results showed significant reduction in SBP (WMD: -0.90 mmHg, 95% CI: -1.74, -0.06, Pheterogeneity = 0.94) by almond intervention. There is no significant effect from almond consumption on DBP (WMD: 0.67 mmHg, 95% CI: -1.93, 0.60, Pheterogeneity = 0.001). Meta-regression analysis showed dose of used almond (g/d) as source of heterogeneity between results of DBP. In conclusion results of this meta-analysis showed reduce effect of almonds on systolic blood pressure.

Snacking on whole almonds for six weeks increases heart rate variability during mental stress in healthy adults: A randomized controlled trial.

Dikariyanto, V., L. Smith, P.J. Chowienczyk, S.E. Berry, W.L. Hall, 2020. Snacking on whole almonds for six weeks increases heart rate variability during mental stress in healthy adults: A randomized controlled trial. Nutrients. 12,1828; doi:10.3390/nu12061828.

Cardiac autonomic regulation can be indirectly measured by heart rate variability (HRV). Low HRV, which can be induced by mental stress, is a predictor of risk of sudden cardiac death. Few studies have investigated cause-and-effect relationships between diet and HRV. Nut consumption is associated with CVD risk reduction, but the impact on HRV, particularly in response to stress, is unclear. Men and women (30–70 y) with above average risk of developing CVD were randomly assigned in a 6-week randomized, controlled, parallel arm trial to consume either whole almond or isocaloric control snacks (20% of daily estimated energy requirement). Control snacks contained the average nutrient profile of UK snacks. Five-minute periods of supine heart rate (HR) and HRV were measured at resting and during mental stress (Stroop color-word test) at baseline and six weeks. High frequency (HF) power, which reflects parasympathetic regulation of HR, was increased following almonds during the mental stress task relative to control (mean difference between groups 124 ms2; 95% CI 11, 237; p = 0.031, n = 105), but other indices were unaffected. Snacking on whole almonds instead of typical snacks may reduce risk of CVD partly by ameliorating the suppression of HRV during periods of mental stress.

Snacking on whole almonds for 6 weeks improves endothelial function and lowers LDL cholesterol but does not affect liver fat and other cardiometabolic risk factors in healthy adults: the ATTIS study, a randomized controlled trial.

Dikariyanto, V., L. Smith, L. Francis, M. Robertson, E. Kusaslan, M. O’Callaghan-Latham, C. Palanche, M. D’Annibale, D. Christodoulou, N. Basty, B. Whitcher, H. Shuaib, G. Charles-Edwards, P.J. Chowienczyk, P.R. Ellis, S.E.E. Berry, W.L. Hall, 2020. Snacking on whole almonds for 6 weeks improves endothelial function and lowers LDL cholesterol but does not affect liver fat and other cardiometabolic risk factors in healthy adults: the ATTIS study, a randomized controlled trial. Am J Clin Nutr. 00:1– 12.

Background: There is convincing evidence that daily whole almond consumption lowers blood LDL cholesterol concentrations, but effects on other cardiometabolic risk factors such as endothelial function and liver fat are still to be determined. Objectives: We aimed to investigate whether isoenergetic substitution of whole almonds for control snacks with the macronutrient profile of average snack intakes, had any impact on markers of cardiometabolic health in adults aged 30–70 y at above-average risk of cardiovascular disease (CVD). Methods: The study was a 6-wk randomized controlled, parallel-arm trial. Following a 2-wk run-in period consuming control snacks (mini-muffins), participants consumed either whole roasted almonds (n = 51) or control snacks (n = 56), providing 20% of daily estimated energy requirements. Endothelial function (flow-mediated dilation), liver fat (MRI/magnetic resonance spectroscopy), and secondary outcomes as markers of cardiometabolic disease risk were assessed at baseline and end point. Results: Almonds, compared with control, increased endothelium-dependent vasodilation (mean difference 4.1%-units of measurement; 95% CI: 2.2, 5.9), but there were no differences in liver fat between groups. Plasma LDL cholesterol concentrations decreased in the almond group relative to control (mean difference −0.25 mmol/L; 95% CI: −0.45, −0.04), but there were no group differences in triglycerides, HDL cholesterol, glucose, insulin, insulin resistance, leptin, adiponectin, resistin, liver function enzymes, fetuin-A, body composition, pancreatic fat, intramyocellular lipids, fecal SCFAs, blood pressure, or 24-h heart rate variability. However, the long-phase heart rate variability parameter, very-low-frequency power, was increased during nighttime following the almond treatment compared with control (mean difference 337 ms2; 95% CI: 12, 661), indicating greater parasympathetic regulation. Conclusions: Whole almonds consumed as snacks markedly improve endothelial function, in addition to lowering LDL cholesterol, in adults with above-average risk of CVD. This trial was registered at clinicaltrials.gov as NCT02907684.

Whole almond consumption is associated with better diet quality and cardiovascular disease risk factors in the UK adult population: National Diet and Nutrition Survey (NDNS) 2008–2017.

Dikariyanto, V., S.E. Berry, L. Francis, L. Smith, W.L. Hall, 2020. Whole almond consumption is associated with better diet quality and cardiovascular disease risk factors in the UK adult population: National Diet and Nutrition Survey (NDNS) 2008–2017. Eur J Nutr. 60(2):643-654.

Purpose: This work aimed to estimate whole almond consumption in a nationally representative UK survey population and examine associations with diet quality and cardiovascular disease (CVD) risk. Methods: Four-day food record data from the National Diet and Nutrition Survey (NDNS) 2008–2017 (n = 6802, age≥19 year) were analyzed to investigate associations between whole almond consumption and diet quality, measured by the modified Mediterranean Diet Score (MDS) and modified Healthy Diet Score (HDS), and CVD risk markers, using survey-adjusted multivariable linear regression. Results: Whole almond consumption was reported in 7.6% of the population. Median intake in whole almond consumers was 5.0 g/day (IQR 9.3). Consumers had higher diet quality scores relative to non-consumers; higher intakes of protein, total fat, monounsaturated, n-3 and n-6 polyunsaturated fats, fiber, folate, vitamin C, vitamin E, potassium, magnesium, phosphorus, and iron; and lower intakes of trans-fatty acids, total carbohydrate, sugar, and sodium. BMI and WC were lower in whole almond consumers compared to non-consumers: 25.5 kg/m2 (95% CI 24.9, 26.2) vs 26.3 kg/m2 (25.9, 26.7), and 88.0 cm (86.2, 89.8) vs 90.1 cm (89.1, 91.2), respectively. However, there were no dose-related fully adjusted significant associations between increasing almond intake (g per 1000 kcal energy intake) and lower CVD risk markers. Conclusions: Almond intake is low in the UK population, but consumption was associated with better dietary quality and lower CVD risk factors. Habitual consumption of whole almonds should be encouraged as part of a healthy diet.