Cohen, A.E., C.S. Johnston, 2011. Almond ingestion at mealtime reduces postprandial glycemia and chronic ingestion reduces hemoglobin A1c in individuals with well-controlled type 2 diabetes mellitus. Metabolism Clinical and Experimental. 60:1312–1317.
Cohort studies are equivocal regarding a relationship between regular nut consumption and reduced risk of type 2 diabetes mellitus. Although acute trials show reductions in postprandial glycemia in healthy individuals ingesting 60 to 90 g almonds, trials have not been conducted using a single serving of almonds (28 g) in individuals with type 2 diabetes mellitus. This randomized crossover trial examined the impact of one serving of almonds at mealtime on postprandial glycemia, insulinemia, and plasma glucagon-like peptide–1 in healthy individuals and individuals with type 2 diabetes mellitus. On 2 occasions separated by at least 1 week, 19 adults (including 7 adults with type 2 diabetes mellitus) consumed a standardized evening meal and fasted overnight before ingesting the test meal (bagel, juice, and butter) with or without almonds. A small pilot study (6-7 subjects per group) was also conducted to observe whether chronic almond ingestion (1 serving 5 d/wk for 12 weeks) lowered hemoglobin A1c in individuals with type 2 diabetes mellitus. A standard serving of almonds reduced postprandial glycemia significantly in participants with diabetes (−30%, P = .043) but did not influence glycemia in participants without diabetes (−7%, P = .638). Insulinemia and glucagon-like peptide–1 at 30 minutes postmeal were not impacted by almond ingestion for either group. In the pilot study, regular almond ingestion for 12 weeks reduced hemoglobin A1c by 4% (P = .045 for interaction) but did not influence fasting glucose concentrations. These data show that modest almond consumption favorably improves both short-term and long-term markers of glucose control in individuals with uncomplicated type 2 diabetes mellitus.
Platt, I.D., A.R. Jossea, C.W.C. Kendall, D.J.A. Jenkins, A. El-Sohemya, 2011. Postprandial effects of almond consumption on human osteoclast precursors—an ex vivo study. Metabolism Clinical and Experimental. 60: 923–929.
Consumption of almonds has been associated with increased bone mineral density, but the direct effects of almonds on bone cells are not known. We determined whether serum obtained following the consumption of a meal containing 60 g of almonds affects human osteoclast formation, function, and gene expression in vitro. Human osteoclast precursors were cultured in medium containing 10% serum obtained from 14 healthy subjects at baseline and 4 hours following the consumption of 3 test meals containing almonds, potatoes, and rice and balanced for macronutrient composition. Osteoclast formation was determined by the number of tartrate-resistant acid phosphatase (TRAP)+ multinucleated cells, and osteoclast function was assessed by measuring TRAP activity in the culture medium and calcium released from OsteoAssay (Lonza Walkersville, Walkersville, MD, USA) plates. The expression of cathepsin K, receptor activator of nuclear factor kB, and matrix metalloproteinase–9 genes was measured by real-time reverse transcriptase–polymerase chain reaction. Compared with serum obtained at baseline, serum obtained 4 hours following the consumption of the almond meal reduced osteoclast formation by approximately 20%, TRAP activity by approximately 15%, calcium release by approximately 65%, and the expression of cathepsin K, receptor activator of nuclear factor kB, and matrix metalloproteinase–9 by 13% to 23%. No effects were observed with serum obtained from the other test meals. Serum obtained 4 hours following the consumption of an almond meal inhibits osteoclast formation, function, and gene expression in cultured human osteoclast precursors, and provides evidence for a positive effect of almonds on bone health.
Kalgaonkar, S., R.U. Almario, D. Gurusinghe, E.M. Garamendi, W. Buchan, K. Kim, S.E. Karakas, 2011. Differential effects of walnuts vs almonds on improving metabolic and endocrine parameters in PCOS. European Journal of Clinical Nutrition. 65:386–393.
Background/Objectives: Polycystic ovary syndrome (PCOS) is commonly associated with insulin resistance, dyslipidemia and increased inflammation, which all benefit from dietary intake of monounsaturated and n-3 polyunsaturated fatty acids (MUFA and n-3 PUFA). Our goal was to compare the effects of MUFA-rich almonds vs n-3/n-6 PUFA-rich walnuts on metabolic and endocrine parameters in PCOS. Subjects/Methods: Thirty-one PCOS patients randomly received either walnuts or almonds containing 31 g of total fat per day for 6 weeks. At the beginning and at the end, anthropometric parameters, fasting lipids, phospholipid-fatty acids, inflammatory markers, androgens, oral glucose tolerance tests (OGTT) and frequently sampled intravenous-GTT were obtained. Results: Weight remained stable. Within group, walnuts increased the n-3/n-6 essential PUFA in the diet and plasma phospholipids. Walnuts decreased low-density lipoprotein-cholesterol by 6% from 3.76±0.27 to 3.38±0.22 mmol/l (P=0.05) and apoprotein B by 11% from 0.72±0.04 to 0.64±0.05 g/l (P<0.03). Although almonds also reduced low-density lipoprotein-cholesterol by 10% and apoprotein B by 9%, these were not significant. Walnuts increased insulin response during OGTT by 26% (P<0.02). Both walnuts and almonds increased adiponectin (walnuts from 9.5±1.6 to 11.3±1.8 mg per 100 ml, P=0.0241; almonds from 10.1±1.5 to 12.2±1.4 mg/dl, P=0.0262). Walnuts decreased HgBA1 from 5.7±0.1 to 5.5±0.1% (P=0.0006) with significant intergroup difference from almonds (P=0.0470). Walnuts increased sex hormone-binding globulin from 38.3±4.1 to 43.1±4.3 nmol/l (P=0.0038) and almonds reduced free androgen index from 2.6±0.4 to 1.8±0.3 (P=0.0470). Conclusion: Nut intake exerted beneficial effects on plasma lipids and androgens in PCOS.
Damasceno, N.R.T., A. Pe´rez-Heras, M. Serra, M. Cofa´n, A. Sala-Vila, J. Salas-Salvado´, E. Ros, 2011. Crossover study of diets enriched with virgin olive oil, walnuts or almonds. Effects on lipids and other cardiovascular risk markers. Nutr Metab Cardiovasc Dis. 21 (Suppl 1):S14-20.
Background and aims: Virgin olive oil (VOO) and nuts are basic components of the Mediterranean diet, a heart-healthy dietary pattern. Nuts have well known cholesterol lowering effects, while evidence is unclear for VOO. We designed a study in hypercholesterolemic patients to assess the effects on serum lipids and other intermediate markers of cardiovascular risk of replacing 40% of the fat in the background diet with VOO, walnuts or almonds. Methods and Results: After a 4 week run-in period with a healthy diet, eligible candidates were randomized into three diet sequences in a crossover design, with a common background diet enriched with VOO, walnuts or almonds, lasting 4 weeks each. Outcomes were changes of serum lipids and oxidation and inflammation markers, measured by standard methods. Plasma fatty acids were determined by gas chromatography to assess compliance. In 18 participants completing the study (9 women, mean age 56 y, BMI 25.7 kg/m2), LDL cholesterol was reduced from baseline by 7.3%, 10.8% and 13.4% after the VOO, walnut and almond diets, respectively (P Z 0.001, Friedman test). Total cholesterol and LDL/HDL ratios decreased in parallel. LDL-cholesterol decreases were greater than predicted from dietary fatty acid and cholesterol exchanges among diets. No changes of other lipid fractions, oxidation analytes or inflammatory biomarkers were observed. Plasma fatty acid changes after each diet sequence supported good compliance.
Casas-Agustench, P., M. Bulló, E. Ros, J. Basora, J. Salas-Salvadó; Nureta-PREDIMED investigators. Collaborators: N. Babio, M. Sorli, C. Molina, F. Márquez-Sandoval, N. Izzedin, J. Marimon, D. Gil, T. Basora, R. Pedret, S.G. Rojas, 2011. Cross-sectional association of nut intake with adiposity in a Mediterranean population. Nutr Metab Cardiovasc Dis. 21(7):518-25.
BACKGROUND AND AIMS: Nut intake has been inversely related to body mass index (BMI) in prospective studies. We examined dietary determinants of adiposity in an elderly Mediterranean population with customarily high nut consumption. METHODS AND RESULTS: A cross-sectional study was conducted in 847 subjects (56% women, mean age 67 years, BMI 29.7kg/m(2)) at high cardiovascular risk recruited into the PREDIMED study. Food consumption was evaluated by a validated semi-quantitative questionnaire, energy expenditure in physical activity by the Minnesota Leisure Time Activity questionnaire, and anthropometric variables by standard measurements. Nut intake decreased across quintiles of both BMI and waist circumference (P-trend <0.005; both). Alcohol ingestion was inversely related to BMI (P-trend=0.020) and directly to waist (P-trend=0.011), while meat intake was directly associated with waist circumference (P-trend=0.018). In fully adjusted multivariable models, independent dietary associations of BMI were the intake of nuts inversely (P=0.002) and that of meat and meat products directly (P=0.042). For waist circumference, independent dietary associations were intake of nuts (P=0.002) and vegetables (P=0.040), both inversely, and intake of meat and meat products directly (P=0.009). From the regression coefficients, it was predicted that BMI and waist circumference decreased by 0.78kg/m(2) and 2.1cm, respectively, for each serving of 30g of nuts. Results were similar in men and women. CONCLUSION: Nut consumption was inversely associated with adiposity independently of other lifestyle variables. It remains to be explored whether residual confounding related to a healthier lifestyle of nut eaters might in part explain these results.
Salas-Salvadó, J., M. Bulló, N. Babio, M.Á. Martínez-González, N. Ibarrola-Jurado, J. Basora, R. Estruch, M.I. Covas, D. Corella, F. Arós, V. Ruiz-Gutiérrez, E. Ros, and for the PREDIMED Study Investigators, 2011. Reduction in the incidence of type 2 diabetes with the Mediterranean diet results of the PREDIMED-Reus nutrition intervention randomized trial. Diabetes Care. 34:14–19.
OBJECTIVE: To test the effects of two Mediterranean diet (MedDiet) interventions versus a low-fat diet on incidence of diabetes. RESEARCH DESIGN AND METHODS: This was a three-arm randomized trial in 418 nondiabetic subjects aged 55–80 years recruited in one center (PREDIMED-Reus, northeastern Spain) of the Prevención con Dieta Mediterránea [PREDIMED] study, a large nutrition intervention trial for primary cardiovascular prevention in individuals at high cardiovascular risk. Participants were randomly assigned to education on a low-fat diet (control group) or to one of two MedDiets, supplemented with either free virgin olive oil (1 liter/week) or nuts (30 g/day). Diets were ad libitum, and no advice on physical activity was given. The main outcome was diabetes incidence diagnosed by the 2009 American Diabetes Association criteria. RESULTS: After a median follow-up of 4.0 years, diabetes incidence was 10.1% (95% CI 5.1–15.1), 11.0% (5.9–16.1), and 17.9% (11.4–24.4) in the MedDiet with olive oil group, the MedDiet with nuts group, and the control group, respectively. Multivariable adjusted hazard ratios of diabetes were 0.49 (0.25–0.97) and 0.48 (0.24–0.96) in the MedDiet supplemented with olive oil and nuts groups, respectively, compared with the control group. When the two MedDiet groups were pooled and compared with the control group, diabetes incidence was reduced by 52% (27–86). In all study arms, increased adherence to the MedDiet was inversely associated with diabetes incidence. Diabetes risk reduction occurred in the absence of significant changes in body weight or physical activity. CONCLUSIONS: MedDiets without calorie restriction seem to be effective in the prevention of diabetes in subjects at high cardiovascular risk.
Jenkins, D.J.A., C.W.C. Kendall, M.S. Banach, K. Srichaikul, E. Vidgen, S. Mitchell, T. Parker, S. Nishi, B. Bashyam, R. de Souza, C. Ireland, R.G. Josse, 2011. Nuts as a replacement for carbohydrates in the diabetic diet. Diabetes Care. 34(8):1706-11.
OBJECTIVE: Fat intake, especially monounsaturated fatty acid (MUFA), has been liberalized in diabetic diets to preserve HDL cholesterol and improve glycemic control, yet the exact sources have not been clearly defined. Therefore, we assessed the effect of mixed nut consumption as a source of vegetable fat on serum lipids and HbA1c in type 2 diabetes. RESEARCH DESIGN AND METHODS: A total of 117 type 2 diabetic subjects were randomized to one of three treatments for 3 months. Supplements were provided at 475 kcal per 2,000-kcal diet as mixed nuts (75 g/day), muffins, or half portions of both. The primary outcome was change in HbA1c. RESULTS: The relative increase in MUFAs was 8.7% energy on the full-nut dose compared with muffins. Using an intention-to-treat analysis (n = 117), full-nut dose (mean intake 73 g/day) reduced HbA1c (−0.21% absolute HbA1c units, 95% CI −0.30 to −0.11, P < 0.001) with no change after half-nut dose or muffin. Full-nut dose was significantly different from half-nut dose (P = 0.004) and muffin (P = 0.001), but no difference was seen between half-nut dose and muffins. LDL cholesterol also decreased significantly after full-nut dose compared with muffin. The LDL cholesterol reduction after half-nut dose was intermediate and not significantly different from the other treatments. Apolipoprotein (apo) B and the apoB:apoA1 ratio behaved similarly. Nut intake related negatively to changes in HbA1c (r = −0.20, P = 0.033) and LDL cholesterol (r = −0.24, P = 0.011). CONCLUSIONS: Two ounces of nuts daily as a replacement for carbohydrate foods improved both glycemic control and serum lipids in type 2 diabetes.
Casas-Agustench, P., P. López-Uriarte, E. Ros, M. Bulló, J. Salas-Salvadó, 2011. Nuts, hypertension and endothelial function. Nutr Metab Cardiovasc Dis. 2011 21(Suppl 1):S21-33.
BACKGROUND AND AIMS: High blood pressure (BP) is considered a major risk factor for cardiovascular disease. Among lifestyle factors, diet plays a key role in the prevention and control of high BP. Therefore, it is important to elucidate which dietary components can exert beneficial effects on BP through modulation of endothelial function (EF) or by other mechanisms. In this paper we review the role of nutrients, foods, particularly nuts, and dietary patterns on BP control. DATA SYNTHESIS: Because nuts are low in sodium and contain significant amounts of mono- and polyunsaturated fatty acids, fiber, minerals such as magnesium, potassium and calcium, and antioxidants, they have been suggested as potentially protective foods against hypertension. Limited evidence from prospective studies and clinical trials suggests that nut consumption has a beneficial effect on both BP and EF. However, BP changes were a secondary outcome in nut feeding trials and no study used ambulatory BP monitoring as the standard for BP measurements. CONCLUSIONS: Further clinical trials, ideally using ambulatory BP monitoring, are needed to establish the potential protective effect of nut consumption on hypertension and vascular reactivity.
Mori, A.M., R.V. Considine, R.D. Mattes, 2011. Acute and second-meal effects of almond form in impaired glucose tolerant adults: a randomized crossover trial. Nutrition & Metabolism. 8(1):6.
Background: Nut consumption may reduce the risk of developing type 2 diabetes. The aim of the current study was to measure the acute and second-meal effects of morning almond consumption and determine the contribution of different nut fractions. Methods: Fourteen impaired glucose tolerant (IGT) adults participated in a randomized, 5-arm, crossover design study where whole almonds (WA), almond butter (AB), defatted almond flour (AF), almond oil (AO) or no almonds (vehicle – V) were incorporated into a 75 g available carbohydrate-matched breakfast meal. Postprandial concentrations of blood glucose, insulin, non-esterified free fatty acids (NEFA), glucagon-like peptide-1 (GLP-1) and appetitive sensations were assessed after treatment breakfasts and a standard lunch. Results: WA significantly attenuated second-meal and daylong blood glucose incremental area under the curve (AUCI) and provided the greatest daylong feeling of fullness. AB and AO decreased blood glucose AUCI in the morning period and daylong blood glucose AUCI was attenuated with AO. WA and AO elicited a greater secondmeal insulin response, particularly in the early postprandial phase, and concurrently suppressed the second-meal NEFA response. GLP-1 concentrations did not vary significantly between treatments. Conclusions: Inclusion of almonds in the breakfast meal decreased blood glucose concentrations and increased satiety both acutely and after a second-meal in adults with IGT. The lipid component of almonds is likely responsible for the immediate post-ingestive response, although it cannot explain the differential second-meal response to AB versus WA and AO.
Willison, L.N., P. Tripathi, G. Sharma, S.S. Teuber, S.K. Sathe, K.H. Roux, 2011. Cloning, expression and patient IgE reactivity of Recombinant Pru du 6, an 11S Globulin from almond. Int Arch Allergy Immunol. 323887 DOI: 10.1159/000323887
Background: IgE-reactive proteins have been identified in almond; however, few have been cloned and tested for specific patient IgE reactivity. Here, we clone and express prunin 1 and prunin 2, isoforms of the major almond protein prunin, an 11S globulin, and assay each for IgE reactivity. Methods: Prunin isoforms were PCR-amplified from an almond cDNA library, sequenced, cloned and expressed in Escherichia coli. Reactivity to the recombinant (r) allergens, Pru du 6.01 and Pru du 6.02, was screened by dot blot and immunoblot assays using sera from almond-allergic patients and murine monoclonal antibodies (mAbs). Sequential IgE-binding epitopes were identified by solid-phase overlapping peptide analysis. Epitope stability was assessed by assaying denatured recombinant proteins by immunoblot. Results: IgE reactivity to rPru du 6.01 and rPru du 6.02 was found in 9 of 18 (50%) and 5 of 18 patients (28%), respectively. Four patients (22%) demonstrated reactivity to both isoforms. Murine anti-almond IgG mAbs also showed greater reactivity to rPru du 6.01 than to rPru du 6.02. Both stable and labile epitopes were detected. Six IgE-binding sequential epitope-bearing peptide segments on Pru du 6.01 and 8 on Pru du 6.02 were detected using pooled almond-allergic sera. Conclusions: rPru du 6.01 is more widely recognized than rPru du 6.02 in our patient population. The identification of multiple sequential epitopes and the observation that treatment with denaturing agents had little effect on IgE-binding intensity in some patients suggests an important role for sequential epitopes on prunins.
