Nishi, S.K., C.W.C. Kendall, R.P. Bazinet, B. Bashyam, C.A. Ireland, L.S.A. Augustin, S. Blanco Mejia, J.L. Sievenpiper, D.J.A. Jenkins, 2014. Nut consumption, serum fatty acid profile and estimated coronary heart disease risk in type 2 diabetes. Nutrition, Metabolism & Cardiovascular Diseases. 24(8):845-852.
Background and aims: Nut consumption has been associated with decreased risk of coronary heart disease (CHD) and type 2 diabetes which has been largely attributed to their healthy fatty acid profile, yet this has not been ascertained. Therefore, we investigated the effect of nut consumption on serum fatty acid concentrations and how these relate to changes in markers of glycemic control and calculated CHD risk score in type 2 diabetes. Methods and results: 117 subjects with type 2 diabetes consumed one of three iso-energetic (mean 475 kcal/d) supplements for 12 weeks: 1. full-dose nuts (50e100 g/d); 2. half-dose nuts with half-dose muffins; and 3. full-dose muffins. In this secondary analysis, fatty acid concentrations in the phospholipid, triacylglycerol, free fatty acid, and cholesteryl ester fractions from fasting blood samples obtained at baseline and week 12 were analyzed using thin layer and gas chromatography. Full-dose nut supplementation significantly increased serum oleic acid (OA) and MUFAs compared to the control in the phospholipid fraction (OA: P = 0.036; MUFAs: P = 0.024). Inverse associations were found with changes in CHD risk versus changes in OA and MUFAs in the triacylglycerol (r = -0.256, P = 0.011; r = -0.228, P = 0.024, respectively) and phospholipid (r = -0.278, P = 0.006; r = -0.260, P = 0.010, respectively) fractions. In the cholesteryl ester fraction, change in MUFAs was inversely associated with markers of glycemic control (HbA1c: r = -0.250, P = 0.013; fasting blood glucose: r = -0.395, P < 0.0001). Conclusion: Nut consumption increased OA and MUFA content of the serum phospholipid fraction, which was inversely associated with CHD risk factors and 10-year CHD risk
Jaceldo-Siegl, K., E. Haddad, K. Oda, G.E. Fraser, J. Sabate´, 2014. Tree nuts are inversely associated with metabolic syndrome and obesity: The Adventist Health Study-2. PLoS ONE 9(1): e85133. doi:10.1371/journal.pone.0085133.
Objective: To examine the relationships of nut consumption, metabolic syndrome (MetS), and obesity in the Adventist Health Study-2, a relatively healthy population with a wide range of nut intake. Research Design and Methods: Cross-sectional analysis was conducted on clinical, dietary, anthropometric, and demographic data of 803 adults. MetS was defined according to the American Heart Association and the National Heart, Lung, and Blood Institute diagnostic criteria. We assessed intake of total nuts, tree nuts and peanuts, and also classified subjects into low tree nut/low peanut (LT/LP), low tree/high peanut (LT/HP), high tree nut/high peanut (HT/HP), and high tree/low peanut (HT/LP) consumers. Odds ratios were estimated using multivariable logistic regression. Results: 32% of subjects had MetS. Compared to LT/LP consumers, obesity was lower in LT/HP (OR = 0.89; 95% CI = 0.53, 1.48), HT/HP (OR = 0.63; 95% CI = 0.40, 0.99) and HT/LP (OR = 0.54; 95% CI = 0.34, 0.88) consumers, p for trend = 0.006. For MetS, odds ratios (95% CI) were 0.77 (0.47, 1.28), 0.65 (0.42, 1.00) and 0.68 (0.43, 1.07), respectively (p for trend = 0.056). Frequency of nut intake (once/week) had significant inverse associations with MetS (3% less for tree nuts and 2% less for total nuts) and obesity (7% less for tree nuts and 3% less for total nuts). Conclusions: Tree nuts appear to have strong inverse association with obesity, and favorable though weaker association with MetS independent of demographic, lifestyle and dietary factors.
Bao, Y., J. Han, F.B. Hu, E.L. Giovannucci, M.J. Stampfer, W.C. Willett, C.S. Fuchs, 2013. Association of nut consumption with total and cause-specific mortality. N Engl J Med. 369:2001-2011.
Background: Increased nut consumption has been associated with a reduced risk of major chronic diseases, including cardiovascular disease and type 2 diabetes mellitus. However, the association between nut consumption and mortality remains unclear. Methods: We examined the association between nut consumption and subsequent total and cause-specific mortality among 76,464 women in the Nurses’ Health Study (1980–2010) and 42,498 men in the Health Professionals Follow-up Study (1986–2010). Participants with a history of cancer, heart disease, or stroke were excluded. Nut consumption was assessed at baseline and updated every 2 to 4 years. Results: During 3,038,853 person-years of follow-up, 16,200 women and 11,229 men died. Nut consumption was inversely associated with total mortality among both women and men, after adjustment for other known or suspected risk factors. The pooled multivariate hazard ratios for death among participants who ate nuts, as compared with those who did not, were 0.93 (95% confidence interval [CI], 0.90 to 0.96) for the consumption of nuts less than once per week, 0.89 (95% CI, 0.86 to 0.93) for once per week, 0.87 (95% CI, 0.83 to 0.90) for two to four times per week, 0.85 (95% CI, 0.79 to 0.91) for five or six times per week, and 0.80 (95% CI, 0.73 to 0.86) for seven or more times per week (P<0.001 for trend). Significant inverse associations were also observed between nut consumption and deaths due to cancer, heart disease, and respiratory disease. Conclusions: In two large, independent cohorts of nurses and other health professionals, the frequency of nut consumption was inversely associated with total and cause-specific mortality, independently of other predictors of death.
Bao, Y., F.B. Hu, E.L. Giovannucci, B.M. Wolpin, M.J. Stampfer, W.C. Willett, C.S. Fuchs, 2013. Nut consumption and risk of pancreatic cancer in women. Br J Cancer. 109(11):2911-2916.
Background: Increasing nut intake has been associated with reduced risk of diabetes mellitus, which is a risk factor for pancreatic cancer. Methods: We prospectively followed 75 680 women in the Nurses’ Health Study, and examined the association between nut consumption and pancreatic cancer risk. Participants with a previous history of cancer were excluded. Nut consumption was assessed at baseline and updated every 2 to 4 years. Relative risks (RRs) and 95% confidence intervals (95% CIs) were estimated using Cox proportional hazards models. Results: We documented 466 incident cases of pancreatic cancer. After adjusting for age, height, smoking, physical activity, and total energy intake, women who consumed a 28-g (1 oz) serving size of nuts ≥2 times per week experienced a significantly lower risk of pancreatic cancer (RR, 0.65; 95% CI, 0.47–0.92; P for trend=0.007) when compared with those who largely abstained from nuts. The results did not appreciably change after further adjustment for body mass index (BMI) and history of diabetes mellitus (RR, 0.68; 95% CI, 0.48–0.95; P for trend=0.01). The inverse association persisted within strata defined by BMI, physical activity, smoking, and intakes of red meat, fruits, and vegetables. Conclusion: Frequent nut consumption is inversely associated with risk of pancreatic cancer in this large prospective cohort of women, independent of other potential risk factors for pancreatic cancer.
Flores-Mateo G., D. Rojas-Rueda, J. Basora, E. Ros, J. Salas-Salvadó, 2013. Nut intake and adiposity: meta-analysis of clinical trials. Am J Clin Nutr. 97(6):1346-1355.
BACKGROUND: Epidemiologic studies have shown an inverse association between the frequency of nut consumption and body mass index (BMI) and risk of obesity. However, clinical trials that evaluated nut consumption on adiposity have been scarce and inconclusive. OBJECTIVE: We performed a systematic review and meta-analysis of published, randomized nut-feeding trials to estimate the effect of nut consumption on adiposity measures. DESIGN: MEDLINE and the Cochrane Central Register of Controlled Trials databases were searched for relevant clinical trials of nut intake that provided outcomes of body weight, BMI (in kg/m2), or waist-circumference measures and were published before December 2012. There were no language restrictions. Two investigators independently selected and reviewed eligible studies. The weighted mean difference (WMD) between nut or control diets was estimated by using a random-effects meta-analysis with 95% CIs. RESULTS: Thirty-three clinical trials met our inclusion criteria. Pooled results indicated a nonsignificant effect on body weight (WMD: -0.47 kg; 95% CI: -1.17, 0.22 kg; I2 = 7%), BMI (WMD: -0.40 kg/m(2); 95% CI: -0.97, 0.17 kg/m(2); I2 = 49%), or waist circumference (WMD: -1.25 cm; 95% CI: -2.82, 0.31 cm; I2 = 28%) of diets including nuts compared with control diets. These findings were remarkably robust in the sensitivity analysis. No publication bias was shown. CONCLUSION: Compared with control diets, diets enriched with nuts did not increase body weight, body mass index, or waist circumference in controlled clinical trials.
Rohrmann, S., D. Faeh, 2013. Should we go nuts about nuts? BMC Medicine. 11:165.
Since the beginning of the 1990s, increasing evidence supports beneficial effects of nut consumption on health. A new analysis of the Spanish PREDIMED trial, published in BMC Medicine, has expanded our knowledge. The study showed that individuals eating nuts more than three times per week died less often from cardiovascular disease and cancer than non-consumers. The study also adds an important finding that previous epidemiological studies could not provide: a protective effect on premature mortality was only seen in the intervention group in which nut consumption increased during the 4.8 years of follow-up, not in the intervention group with additional olive oil consumption or in the control group. Nut consumption actually decreased during follow-up in the latter two groups. Questions remain to be answered on the quantity of nuts to be consumed for health benefits, on possible mechanisms of action, and on whether some types of nuts should be favored.
Guasch-Ferré, M., M. Bulló, M.Á. Martínez-González, E. Ros, D. Corella, R. Estruch, M. Fitó, F. Arós, J. Wärnberg, M. Fiol, J. Lapetra, E. Vinyoles, R.M. Lamuela-Raventós, L. Serra-Majem, X. Pintó, V. Ruiz-Gutiérrez, J. Basora, J. Salas-Salvadó, on behalf of the PREDIMED study group, 2013. Frequency of nut consumption and mortality risk in the PREDIMED nutrition intervention trial. BMC Med. 11:164.
Background: Prospective studies in non-Mediterranean populations have consistently related increasing nut consumption to lower coronary heart disease mortality. A small protective effect on all-cause and cancer mortality has also been suggested. To examine the association between frequency of nut consumption and mortality in individuals at high cardiovascular risk from Spain, a Mediterranean country with a relatively high average nut intake per person. Methods: We evaluated 7,216 men and women aged 55 to 80 years randomized to 1 of 3 interventions (Mediterranean diets supplemented with nuts or olive oil and control diet) in the PREDIMED (‘PREvención con DIeta MEDiterránea’) study. Nut consumption was assessed at baseline and mortality was ascertained by medical records and linkage to the National Death Index. Multivariable-adjusted Cox regression and multivariable analyses with generalized estimating equation models were used to assess the association between yearly repeated measurements of nut consumption and mortality. Results: During a median follow-up of 4.8 years, 323 total deaths, 81 cardiovascular deaths and 130 cancer deaths occurred. Nut consumption was associated with a significantly reduced risk of all-cause mortality (P for trend <0.05, all). Compared to non-consumers, subjects consuming nuts >3 servings/week (32% of the cohort) had a 39% lower mortality risk (hazard ratio (HR) 0.61; 95% CI 0.45 to 0.83). A similar protective effect against cardiovascular and cancer mortality was observed. Participants allocated to the Mediterranean diet with nuts group who consumed nuts >3 servings/week at baseline had the lowest total mortality risk (HR 0.37; 95% CI 0.22 to 0.66). Conclusions: Increased frequency of nut consumption was associated with a significantly reduced risk of mortality in a Mediterranean population at high cardiovascular risk.
Blom, W.M., B.J. Vlieg-Boerstra, A.G. Kruizinga, S. van der Heide, G.F. Houben, A.E.J. Dubois, 2013. Threshold dose distributions for 5 major allergenic foods in children. J Allergy Clin Immunol. 131:172-9.
Background: For most allergenic foods, insufficient threshold dose information within the population restricts the advice on levels of unintended allergenic foods which should trigger precautionary labeling on prepackaged foods. Objective: We wanted to derive threshold dose distributions for major allergenic foods and to elaborate the protein doses at which a proportion of the allergic population is likely to respond. Methods: For 7 allergenic foods double-blind, placebo-controlled food challenges (DBPCFCs) with a positive outcome for allergic reactions were selected from the clinical database of children routinely tested to diagnose food allergy at the University Medical Center Groningen. For each allergen 2 population threshold distributions were determined with the individual minimal eliciting dose and the preceding dose of each DBPCFC for objective symptoms and any symptom (either subjective or objective). Results: Individual positive DBPCFCs were available for peanut (n = 135), cow’s milk (n = 93), hen’s egg (n = 53), hazelnut (n = 28), and cashew nut (n = 31). Fewer children were challenged with soy (n = 10) or walnut (n = 13). Threshold dose distributions showed a good statistical and visual fit. The protein dose at which 5% of the allergic population is likely to respond with objective reactions was 1.6 mg for peanut, 1.1 mg for cow’s milk, 1.5 mg for hen’s egg, 7.4 mg for cashew nut, and 0.29 mg for hazelnut. Thresholds for any symptom were on average 2 to 6 times lower than for objective symptoms. The 95% upper and lower confidence intervals of the threshold distributions were overlapping. The peanut threshold distribution on objective symptoms was similar to the distribution of another European center. Conclusions: Threshold distribution curves and eliciting doses are a powerful tool to compare different allergenic foods and for informing policy on precautionary labeling.
Martínez-Lapiscina, E.H., P. Clavero, E. Toledo, R. Estruch, J. Salas-Salvadó, B. San Julián, A. Sanchez-Tainta, E. Ros, C. Valls-Pedret, M.Á. Martinez-Gonzalez, 2013. Mediterranean diet improves cognition: the PREDIMED-NAVARRA randomized trial. J Neurol Neurosurg Psychiatry. doi:10.1136/jnnp-2012-304792.
Objective: Previous observational studies reported beneficial effects of the Mediterranean diet (MedDiet) on cognitive function, but results were inconsistent. We assessed the effect on cognition of a nutritional intervention using MedDiets in comparison with a low-fat control diet. Methods: We assessed 522 participants at high vascular risk (44.6% men, age 74.6 ± 5.7 years at cognitive evaluation) enrolled in a multicentre, randomised, primary prevention trial (PREDIMED), after a nutritional intervention comparing two MedDiets (supplemented with either extra-virgin olive oil (EVOO) or mixed nuts) versus a low-fat control diet. Global cognitive performance was examined by Mini-Mental State Examination (MMSE) and Clock Drawing Test (CDT) after 6.5 years of nutritional intervention. Researchers who assessed the outcome were blinded to group assignment. We used general linear models to control for potential confounding. Results: After adjustment for sex, age, education, Apolipoprotein E genotype, family history of cognitive impairment/dementia, smoking, physical activity, body mass index, hypertension, dyslipidaemia, diabetes, alcohol and total energy intake, participants allocated to the MedDiet+EVOO showed higher mean MMSE and CDT scores with significant differences versus control (adjusted differences: +0.62 95% CI +0.18 to +1.05, p=0.005 for MMSE, and +0.51 95% CI +0.20 to +0.82, p=0.001 for CDT). The adjusted means of MMSE and CDT scores were also higher for participants allocated to the MedDiet+Nuts versus control (adjusted differences: +0.57 (95% CI +0.11 to +1.03), p=0.015 for MMSE and +0.33 (95% CI +0.003 to +0.67), p=0.048 for CDT). These results did not differ after controlling for incident depression. Conclusions: An intervention with MedDiets enhanced with either EVOO or nuts appears to improve cognition compared with a low-fat diet.
Tey, S.L., A.R. Gray, A.W. Chisholm, C. M. Delahunty, R. C. Brown, 2013. The dose of hazelnuts influences acceptance and diet quality but not inflammatory markers and body composition in overweight and obese individuals. J. Nutr. doi: 10.3945/jn.113.174714.
Regular nut consumption may improve markers of inflammation and endothelial dysfunction. The quantity of nuts required to achieve these health benefits without compromising body weight and acceptance is unknown. This study compared the effects of incorporating hazelnuts at 2 different doses with a diet without nuts on inflammatory markers, cell adhesion molecules, and body composition in 107 overweight and obese individuals. This was a randomized, controlled, parallel 12-wk intervention including 3 treatment arms: no nuts (control group), 30 g/d of hazelnuts, or 60 g/d of hazelnuts. Blood pressure, body composition, plasma high-sensitivity C-reactive protein (hs-CRP), interleukin 6 (IL-6), intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), lipid, and apolipoprotein (apo) profiles were assessed at baseline and at 6 and 12 wk. ‘‘Desire’’ and ‘‘liking’’ for nuts were assessed during the intervention. Results showed no significant differences in follow-up clinical outcomes between groups after adjusting for baseline values, age, sex, and BMI (all P ≥ 0.10), except for a tendency toward improvement in VCAM-1 concentration in the 60-g/d nut group (P = 0.07). Hazelnut consumption significantly improved diet quality in a dose-response manner. Desire and liking for nuts remained stable in the 30-g/d group, whereas these ratings decreased significantly over time in the 60-g/d group (both P < 0.001). In conclusion, 12 wk of hazelnut consumption appears to have minimal effect on inflammatory markers and cell adhesion molecules in this group of healthy, normocholesterolemic overweight and obese individuals. Nut consumption improves diet quality without adversely affecting body composition. Consuming 30 g/d of nuts regularly is achievable, whereas 60 g/d appears to compromise desire and liking.
