IJCS | Volume 32, Nº2, May/June 2019

276 Table 2 - Effects of nut consumption on cardiovascular risk factors Study population Intervention Duration Main outcomes American adults (14,386) 8 ≥ ¼ ounce/day of tree nuts (almonds, Brazil nuts, cashews, hazelnuts, macadamias, pecans, pine nuts, pistachios and walnuts) 2 multiple pass 24-h dietary recalls Decreased body mass index, waist circumference, blood pressure, insulin resistance Increased HDL-c Lowered chances of obesity and overweight CAD patients with optimal LDL-c and low HDL-c (37) 9 10 g/day of Pakistan or American almonds 6 weeks Increased HDL-c Decreased TG, LDL-c, VLDL-c, TC/HDL-c and LDL/HDL-c ratio and atherogenic index Indian dyslipidemic adults (60) 10 80 g/day of pistachios in shell, roasted and salted 12 weeks Increased HDL-c Decreased LDL-c, TC/HDL-c ratio and fasting blood glucose Improved vascular function Adults with well-controlled type 2 diabetes (30) 11 Roasted pistachios that provided 20% of daily energy (59 to 128 g) 4 weeks Decreased TC, TC/HDL-c ratio, TG and fructosamine Hypercholesterolemic patients (18) 12 Virgin olive oil (35 to 50 g/day), almonds (50 to 75 g/day) and walnuts (40 to 6 g/day) 4 weeks Decreased TC, LDL-c, LDL/HDL-c ratio (results were more expressive with the almonds supplementation, possibly due to the greater content of phytosterol) Adults with metabolic syndrome (50) 17 Mixed raw nuts with skin (15 g/day of walnuts, 7.5 g/day of almonds, 7.5 g/day of hazelnuts) 12 weeks Decreased DNA damage (measured by 8-oxo-dG urinary excretion), inflammatory biomarker (IL-6) Subjects at increased cardiovascular risk (22) 19 300 g of walnut paste-enriched meat/ week (containing 20% walnut paste) 5 weeks Decreased sVCAM, sICAM and Leukotriene B4 Hypercholesterolemic volunteers (21) 20 49 to 86 g/day hazelnut enriched diet 4 weeks Decreased CRP and sVCAM Improved endothelial dysfunction HDL-c: high-density lipoprotein cholesterol; TG: trygliceridies; LDL-c: low-density lipoprotein cholesterol; VLDL-c: very low-density lipoprotein cholesterol; TC: total cholesterol; IL-6: interleukin 6; sVCAM: soluble vascular cell adhesion molecule, sICAM: soluble intercellular cell adhesion molecule; CRP: C-reactive protein. Silva et al. Nuts and cardiovascular diseases Int J Cardiovasc Sci. 2019;32(3)274-282 Review Article showed to have the greatest hypocholesterolemic effect, which could be explained by the presence the higher content of phytosterol in almonds compared with olive oil and walnuts. 12 One of the hypothesis for the hypocholesterolemic effect of nuts is their high amounts of phytosterols. Phytosterols are non-nutritive components of plants that play an important structural role in membranes, where they serve to stabilize phospholipid bilayers just as cholesterol does in animal cell membranes. 6 These compounds are able to displace cholesterol from intestinal micelles thereby reducing its absorption and leading to a reduction in LDL-c and TC (Figure 1). 4,13 Nuts are also an important factor to modulate hypertension, since MUFA and PUFA are able to reduce serum levels of thromboxane A2, which is a vasoconstrictor. 4 In addition, the mineral content of nuts develops a key role in hypertension, as magnesium found in nuts stimulates the production of nitrous oxide, a vasodilator, and blocks the calcium channels, promoting vasodilatation. Furthermore, potassium can modulate the extracellular fluid volume reducing peripheral vascular resistance (Figure 1). 4,14 A review study investigating the association between nut consumption, hypertension and endothelial dysfunction showed that there are insufficient epidemiological data associating nuts with the prevention of hypertension, 14 which was reported in only two prospective studies. The first study was a prospective cohort conducted by Djousse et al., 15 with participants from the Physicians Health Study I, who were free of hypertension at