Sabate´, J., K. Oda, E. Ros, 2010. Nut Consumption and Blood Lipid Levels A Pooled Analysis of 25 Intervention Trials. Arch Intern Med. 170(9):821-827.
Background: Epidemiological studies have consistently associated nut consumption with reduced risk for coronary heart disease. Subsequently, many dietary intervention trials investigated the effects of nut consumption on blood lipid levels. The objectives of this study were to estimate the effects of nut consumption on blood lipid levels and to examine whether different factors modify the effects. Methods: We pooled individual primary data from 25 nut consumption trials conducted in 7 countries among 583 men and women with normolipidemia and hypercholesterolemia who were not taking lipid-lowering medications. In a pooled analysis, we used mixed linear models to assess the effects of nut consumption and the potential interactions. Results: With a mean daily consumption of 67 g of nuts, the following estimated mean reductions were achieved: total cholesterol concentration (10.9 mg/dL [5.1% change]), low-density lipoprotein cholesterol concentration (LDL-C) (10.2 mg/dL [7.4% change]), ratio of LDL-C to high-density lipoprotein cholesterol concentration (HDL-C) (0.22 [8.3% change]), and ratio of total cholesterol concentration to HDL-C (0.24 [5.6% change]) (P<.001 for all) (to convert all cholesterol concentrations to millimoles per liter, multiply by 0.0259). Triglyceride levels were reduced by 20.6 mg/dL (10.2%) in subjects with blood triglyceride levels of at least 150 mg/dL (P<.05) but not in those with lower levels (to convert triglyceride level to millimoles per liter, multiply by 0.0113). The effects of nut consumption were dose related, and different types of nuts had similar effects on blood lipid levels. The effects of nut consumption were significantly modified by LDL-C, body mass index, and diet type: the lipid-lowering effects of nut consumption were greatest among subjects with high baseline LDL-C and with low body mass index and among those consuming Western diets. Conclusion: Nut consumption improves blood lipid levels in a dose-related manner, particularly among subjects with higher LDL-C or with lower BMI.
Torabian S., E. Haddad, Z. Cordero-MacIntyre, J. Tanzman, M.L. Fernandez, J. Sabate, 2010. Long-term walnut supplementation without dietary advice induces favorable serum lipid changes in free-living individuals. Eur J Clin Nutr. 64(3):274-9.
BACKGROUND/OBJECTIVES: Walnuts have been shown to reduce serum lipids in short-term well-controlled feeding trials. Little information exists on the effect and sustainability of walnut consumption for longer duration in a free-living situation. SUBJECTS/METHODS: A randomized crossover design in which 87 subjects with normal to moderate high plasma total cholesterol were initially assigned to a walnut-supplemented diet or habitual (control) diet for a 6-month period, then switched to the alternate dietary intervention for a second 6-month period. Each subject attended seven clinics 2 months apart. At each clinic, body weight was measured, and in five clinics (months 0, 4, 6, 10 and 12), a blood sample was collected. RESULTS: Our study showed that supplementing a habitual diet with walnuts (12% of total daily energy intake equivalent) improves the plasma lipid profile. This beneficial effect was more significant in subjects with high plasma total cholesterol at baseline. Significant changes in serum concentrations of total cholesterol (P=0.02) and triglycerides (P=0.03) were seen and nearly significant changes in low-density lipoprotein cholesterol (LDL-C) (P=0.06) were found. No significant change was detected in either high-density lipoprotein (HDL) cholesterol LDL to HDL ratio. CONCLUSIONS: Including walnuts as part of a habitual diet favorably altered the plasma lipid profile. The lipid-lowering effects of walnuts were more evident among subjects with higher lipid baseline values, precisely those people with greater need of reducing plasma total and LDL-C.
Razquin, C., J.A. Martínez, M.A. Martínez-González, J. Salas-Salvadó, R. Estruch, A. Marti, 2010. A 3-year Mediterranean-style dietary intervention may modulate the association between adiponectin gene variants and body weight change. Eur J Nutr. 49(5):311-9.
Purpose Adiponectin gene variations have been associated with obesity. There are few interventional studies analyzing this association. The aim of this study was to analyze the effects of a nutritional intervention with Mediterranean-style diet and three (-4034A/C, +45T/G, and +276 G/T) adiponectin gene variants on 3-year body weight changes in high cardiovascular risk patients. Subjects and methods A total of 737 participants, aged 55–80 at high cardiovascular risk were assigned to a low-fat diet or to a Mediterranean-style diet (MD) groups, one with high intake of virgin olive oil (VOO) and the other with high intake of nuts. Anthropometric parameters were taken at baseline and after 3-year follow-up, and the genotyping of the -4034A/C, +45T/G, and +276 G/T polymorphisms was done. Results GG genotype of the +45T/G polymorphism was associated with 3-year higher body weight gain (B = 1.399; B = 0.043). TT genotype of the +276G/T polymorphism was linked to the highest 3-year body weight gain in men. Both Mediterranean diets appeared to reverse this effect (p for interaction = 0.053). Conclusion Adiponectin gene variation appeared to be associated with 3-year body weight changes in a high cardiovascular risk population. This association may be modulated by a nutritional intervention with a Mediterranean-style diet.
Sala-Vila, A., M. Cofán, A. Pérez-Heras, I. Núñez, R. Gilabert, M. Junyent, R. Mateo-Gallego, A. Cenarro, F. Civeira, E. Ros, 2010. Fatty acids in serum phospholipids and carotid intima-media thickness in Spanish subjects with primary dyslipidemia. Am J Clin Nutr. 92:186-193.
Background: Low rates of incident ischemic heart disease (IHD) and cardiac death occur in Spain despite a high prevalence of cardiovascular risk factors. High consumption of unsaturated fatty acid–rich foods, such as olive oil, nuts, and seafood, might underlie this paradox. Objective: We investigated whether serum phosphatidylcholine enrichment in oleic, linoleic, α-linolenic, and n-3 (omega-3) long-chain polyunsaturated fatty acids (as biomarkers of olive oil, seed oil, walnut, and fish intake, respectively) relate to carotid atherosclerosis in Spanish subjects at risk of IHD. Design: In a cross-sectional study, we measured fatty acid concentrations in serum phosphatidylcholine and measured carotid intima-media thickness (IMT) by using ultrasound in 451 asymptomatic subjects (261 men, 190 women; mean age: 45 y) with primary dyslipidemia. Main and secondary outcomes were mean and maximum IMT in the common carotid artery (CCA) and other carotid segments, respectively. Results: Phosphatidylcholine fatty acid composition was similar to that reported for other Spanish populations. Multiple regression analyses showed that proportions of oleic and docosahexaenoic acids were inversely related to mean CCA IMT (P < 0.02, all) after adjustment for several confounders. In similar models, a-linolenic acid related inversely to mean and maximum internal carotid artery IMT (P < 0.05 for all). Linoleic and eicosapentaenoic acids were unrelated to IMT. Conclusions: Higher phospholipid proportions of oleic, α-linolenic, and docosahexaenoic acids showed inverse associations with IMT at specific carotid segments in subjects with primary dyslipidemia. High intakes of healthy fats might explain, in part, the Spanish paradox of low IHD rates in the face of a high burden of cardiovascular risk factors.
Sala-Vila, A., M. Cofán, I. Núñez, R. Gilabert, M. Junyent, E. Ros, 2010. Carotid and femoral plaque burden is inversely associated with the α-linolenic acid proportion of serum phospholipids in Spanish subjects with primary dyslipidemia. Atherosclerosis. 214:209-214.
Objective: α-Linolenic acid (ALA), the vegetable n-3fatty acid, appears to have antiatherosclerotic prop- erties akin to those of marine n-3 fatty acids. A prior study in a US population with low fish intake showed an inverse association between ALA intake and carotid plaque. We examined the association between the ALA status and advanced carotid and femoral atherosclerosis in subjects at high cardiovascular disease risk from Spain, a country with low coronary heart disease (CHD) rates and high fish consumption. Methods: Cross-sectional study of 211 patients with primary dyslipidemia, with determination of fatty acid composition of serum phosphatidylcholine by gas chromatography and plaque outcomes (frequency, number, maximum height and sum of plaque heights) in carotid and femoral arteries by sonography. Results: In multivariate regression analyses after adjusting for age, gender, lipid genotype, BMI, smoking, hypertension, diabetes mellitus, APOE4 genotype, prior statin treatment, and serum proportions of other unsaturated fatty acids known to relate to atherosclerosis, the proportion of ALA showed an inverse association with the risk of carotid plaque (OR [95%CI] 0.66 [0.44–0.91]) and concomitant carotid and femoral artery plaque (0.57 [0.38–0.86]). Conclusion: The inverse relationship between ALA in serum phosphatidylcholine and plaque burden in carotid and femoral arteries supports its antiatherosclerotic effect independently of fish-derived n-3 fatty acids. However, whether ALA enrichment in phospholipids is beneficial per se or is a surrogate of the consumption of bioactive compounds in parent foods deserves further research.
Ros, E., L.C. Tapsell, J. Sabaté, 2010. Nuts and berries for heart health. Curr Atheroscler Rep. 12:397–406.
Nuts are nutrient-dense foods with complex matrices rich in unsaturated fatty acids and other bioactive compounds, such as L-arginine, fiber, minerals, tocopherols, phytosterols, and polyphenols. By virtue of their unique composition, nuts are likely to beneficially impact heart health. Epidemiologic studies have associated nut consumption with a reduced incidence of coronary heart disease in both genders and diabetes in women. Limited evidence also suggests beneficial effects on hypertension and inflammation. Interventional studies consistently show that nut intake has a cholesterol-lowering effect and there is emerging evidence of beneficial effects on oxidative stress, inflammation, and vascular reactivity. Blood pressure, visceral adiposity, and glycemic control also appear to be positively influenced by frequent nut consumption without evidence of undue weight gain. Berries are another plant food rich in bioactive phytochemicals, particularly flavonoids, for which there is increasing evidence of benefits on cardiometabolic risk that are linked to their potent antioxidant power.
Jalali-Khanabadi, B-A., H. Mozaffari-Khosravi, N. Parsaeyan, 2010. Effects of almond dietary supplementation on coronary heart disease lipid risk factors and serum lipid oxidation parameters in men with mild hyperlipidemia. The Journal of Alternative and Complementary Medicine. 16(12):1–5.
Objectives: Oxidation and level of plasma lipids are closely implicated in the development of coronary heart disease (CHD). Dietary almond supplementation may participate in beneficial effects on CHD lipid risk factor levels and their susceptibility to oxidative modification. The aim of this study was to evaluate the effects of dietary supplementation with almond on serum lipid levels and their relation to lipid oxidation parameters in men with mild hyperlipidemia. Design: Thirty (30) healthy volunteer men (age 45.57 ± 7.14 years and body–mass index 24.29 ± 2.15 g/m2) with mild hyperlipidemia received 60 g almond daily for 4 weeks. Outcome measures: Overnight fasting blood samples were obtained before and after supplementation. Serum levels of lipids, lipoproteins, and apolipoproteins and copper-induced serum lipid oxidation were determined. Lipid oxidation was followed by monitoring of the change of conjugated dienes in diluted serum after addition of Cu2+. A number of quantitative parameters including lag-time, maximal rate of oxidation (V-max), and maximal amount of lipid peroxide products (OD-max) were evaluated. Results: After 4 weeks, almond supplementation significantly decreased low-density lipoprotein cholesterol, total cholesterol (TC), and apolipoprotein B100 (apo-B100). At baseline, there was little correlation between lipid risk factors and lipid oxidation parameters, but a positive correlation was observed between TC and lag-time (r = 0.6, p = 0.001), negative correlation between TC with V-max and OD-max (r = -0.65, p<0.001 and r = -0.61, p = 0.001), and also positive correlation between apo-B100 with V-max and OD-max (r = 0.48, p = 0.01 and R = 0.54, p = 0.003) after almond supplementation. Conclusions: These results demonstrated that almond supplementation, in addition to lowering effects on serum levels of CHD lipid risk factors, may contribute to a dramatic change in the relation of lipid risk factors and susceptibility of serum lipids to oxidative modification. This may be due to the distribution of different almond phenolic antioxidants in different components of serum including nonlipoprotein molecules such as serum albumin.
Kay, C.D., S.K. Gebauer, S.G. West, P.M. Kris-Etherton, 2010. Pistachios increase serum antioxidants and lower serum oxidized-LDL in hypercholesterolemic adults. J. Nutr. doi: 10.3945/jn.109.117366.
Pistachios are high in lutein, b-carotene, and g-tocopherol relative to other nuts; however, studies of the effects of pistachios on oxidative status are lacking. We conducted a randomized, crossover controlled-feeding study to evaluate 2 doses of pistachios on serum antioxidants and biomarkers of oxidative status in 28 hypercholesterolemic adults (LDL cholesterol ≥2.86 mmol/L). Participants consumed 3 isoenergetic diets for 4 wk each after a 2-wk baseline Western diet.
Experimental diets included a lower-fat control diet without pistachios (25% total fat) with 1 serving/d (i.e. 32–63 g/d; energy adjusted) of pistachios (1 PD; 10% energy from pistachios; 30% total fat) or with 2 servings/d (63–126g/d; energy adjusted) of pistachios (2 PD; 20% energy from pistachios; 34% total fat). When participants consumed the pistachioenriched diets, they had higher plasma lutein (P<0.0001), α-carotene, and β-carotene (P<0.01) concentrations than after the baseline diet. After consuming the pistachio diets, participants had greater plasma lutein (P<.001) and g-tocopherol (P<0.05; 2 PD only) relative to the lower-fat control diet. After the 2 PD diet period, participants also had lower serum oxidized-LDL concentrations than following the baseline diet period (P<0.05). After both the 1 PD and 2 PD diet periods, they had lower serum oxidized-LDL concentrations than after the control diet period (P<0.05). The change in oxidized-LDL from baseline correlated positively with the change in LDL-cholesterol across all treatments (r = 0.42; P<0.005). After controlling for the change in serum LDL-cholesterol as a covariate, increases in serum lutein and g-tocopherol following the 2 PD period were still modestly associated with decreases in oxidized-LDL (r = 20.36, P = 0.06 and r =20.35, P = 0.08, respectively). This suggests that a heart-healthy diet including pistachios contributes to the decrease in the serum oxidized-LDL concentration through cholesterol-lowering and may provide an added benefit as a result of the antioxidants the pistachios contain.
Li, S.-C., Y.-H. Liu, W.-H. Chang, C.-M. Chen, C.-Y. O. Chen, J.-F. Liu. 2010. Almond consumption improved glycemic control and lipid profiles in patients with type 2 diabetes. Metabolism.doi:10.1016/j.metabol.2010.04.009.
Almond consumption is associated with ameliorations in obesity, hyperlipidemia, hypertension, and hyperglycemia. The hypothesis of this 12-week randomized crossover clinical trial was that almond consumption would improve glycemic control and decrease the risk for cardiovascular disease in 20 Chinese patients with type 2 diabetes mellitus (T2DM) (9 male, 11 female; 58 years old; body mass index, 26 kg/m(2)) with mild hyperlipidemia. After a 2-week run-in period, patients were assigned to either a control National Cholesterol Education Program step II diet (control diet) or an almond diet for 4 weeks, with a 2-week washout period between alternative diets. Almonds were added to the control diet to replace 20% of total daily calorie intake. Addition of approximately 60 g almonds per day increased dietary intakes of fiber, magnesium, polyunsaturated fatty acid, monounsaturated fatty acid, and vitamin E. Body fat determined with bioelectrical impedance analysis was significantly lower in patients consuming almonds (almonds vs control: 29.6% vs 30.4%). The almond diet enhanced plasma alpha-tocopherol level by a median 26.8% (95% confidence intervals, 15.1-36.6) compared with control diet. Furthermore, almond intake decreased total cholesterol, low-density lipoprotein cholesterol, and the ratio of low-density lipoprotein cholesterol to high-density lipoprotein cholesterol by 6.0% (1.6-9.4), 11.6% (2.8-19.1), and 9.7% (0.3-20.9), respectively. Plasma apolipoprotein (apo) B levels, apo B/apo A-1 ratio, and nonesterified fatty acid also decreased significantly by 15.6% (5.1-25.4), 17.4% (2.8-19.9), and 5.5% (3.0-14.4), respectively. Compared with subjects in the control diet, those in the almond diet had 4.1% (0.9-12.5), 0.8% (0.4-6.3), and 9.2% (4.4-13.2) lower levels of fasting insulin, fasting glucose, and homeostasis model assessment of insulin resistance index, respectively. Our results suggested that incorporation of almonds into a healthy diet has beneficial effects on adiposity, glycemic control, and the lipid profile, thereby potentially decreasing the risk for cardiovascular disease in patients with type 2 diabetes mellitus.
López-Uriarte P, R. Nogués, G. Saez, M. Bulló, M. Romeu, L. Masana, C. Tormos, P. Casas-Agustench, J. Salas-Salvadó, 2010. Effect of nut consumption on oxidative stress and the endothelial function in metabolic syndrome. Clin Nutr. 29(3):373-80.
BACKGROUND & AIMS: Oxidative stress has a key role in atherosclerosis, cancer and other chronic diseases. Some bioactive compounds in nuts have been implicated in antioxidant activities. OBJECTIVE: We assessed how nut consumption affected several markers of oxidation and endothelial function (EF) in metabolic syndrome (MetS) patients. PATIENTS AND METHODS: A randomized, controlled, parallel feeding trial was conducted on 50 MetS adults who were recommended a healthy diet supplemented or not with 30 g of mixed nuts (Nut and Control groups, respectively) every day for 12 weeks. The plasma antioxidant capacity (AC), oxidized LDL (oxLDL), conjugated diene (CD) formation, urine 8-isoprostanes, DNA damage assessed by yield of urine 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxo-dG), and EF assessed by peripheral artery tonometry (PAT) and biochemical markers, were measured at baseline and the end of the intervention. RESULTS: No significant differences in changes between groups were observed in AC, oxLDL, CD, 8-isoprostanes or EF during the intervention, whereas the reduction in DNA damage was significant in the Nut group compared to Control group (P < 0.001). CONCLUSION: Nut consumption has no deleterious effect on lipid oxidation. The decrease in DNA damage observed in this study could contribute to explain the beneficial effects of regular nut consumption on some MetS features and several chronic diseases.
