Casas-Agustench, P., A. Salas-Huetos, J. Salas-Salvado´, 2011. Mediterranean nuts: origins, ancient medicinal benefits and symbolism. Public Health Nutrition: 14(12A): 2296–2301.
Objective: To consider historical aspects of nuts in relation to origin and distribution, attributed medicinal benefits, symbolism, legends and superstitions. Design: Review of historical aspects of nuts. Setting: Mediterranean region. Subjects: The varieties reviewed include almonds, walnuts, hazelnuts, pine nuts and pistachios. Results and conclusions: Like other foods, nuts have a wide variety of cultural connections to the areas where they grow and to the people who live there or eat them. History, symbolism and legends reveal the ancient tradition of nuts and how they are related to the lives of our ancestors. Archaeological excavations in eastern Turkey have uncovered the existence of a non-migratory society whose economy centered on harvesting nuts. This shows that nuts have been a staple in the human diet since the beginnings of history. Moreover, since ancient times nuts have been used for their medicinal properties. They also play a role in many old legends and traditions.
Bolling, B.W., C.-Y. O. Chen, D.L. McKay, J.B. Blumberg, 2011. Tree nut phytochemicals: composition, antioxidant capacity, bioactivity, impact factors. A systematic review of almonds, Brazils, cashews, hazelnuts, macadamias, pecans, pine nuts, pistachios and walnuts. Nutrition Research Reviews 24:244–275
Tree nuts contain an array of phytochemicals including carotenoids, phenolic acids, phytosterols and polyphenolic compounds such as flavonoids, proanthocyanidins (PAC) and stilbenes, all of which are included in nutrient databases, as well as phytates, sphingolipids, alkylphenols and lignans, which are not. The phytochemical content of tree nuts can vary considerably by nut type, genotype, pre- and post-harvest conditions, as well as storage conditions. Genotype affects phenolic acids, flavonoids, stilbenes and phytosterols, but data are lacking for many other phytochemical classes. During the roasting process, tree nut isoflavones, flavanols and flavonols were found to be more resistant to heat than the anthocyanins, PAC and trans-resveratrol. The choice of solvents used for extracting polyphenols and phytosterols significantly affects their quantification, and studies validating these methods for tree nut phytochemicals are lacking. The phytochemicals found in tree nuts have been associated with antioxidant, anti-inflammatory, anti-proliferative, antiviral, chemopreventive and hypocholesterolaemic actions, all of which are known to affect the initiation and progression of several pathogenic processes. While tree nut phytochemicals are bioaccessible and bioavailable in humans, the number of intervention trials conducted to date is limited. The objectives of the present review are to summarize tree nut: (1) phytochemicals; (2) phytochemical content included in nutrient databases and current publications; (3) phytochemicals affected by pre- and post-harvest conditions and analytical methodology; and (4) bioactivity and health benefits in humans.
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.
Mozaffarian, D., T. Hao, E.B. Rimm, W.C. Willett, F.B. Hu, 2011. Changes in diet and lifestyle and long-term weight gain in women and men. N Engl J Med 2011; 364:2392-2404.
Background: Specific dietary and other lifestyle behaviors may affect the success of the straightforward-sounding strategy “eat less and exercise more” for preventing long-term weight gain. Methods: We performed prospective investigations involving three separate cohorts that included 120,877 U.S. women and men who were free of chronic diseases and not obese at baseline, with follow-up periods from 1986 to 2006, 1991 to 2003, and 1986 to 2006. The relationships between changes in lifestyle factors and weight change were evaluated at 4-year intervals, with multivariable adjustments made for age, baseline body-mass index for each period, and all lifestyle factors simultaneously. Cohort-specific and sex-specific results were similar and were pooled with the use of an inverse-variance–weighted meta-analysis. Results: Within each 4-year period, participants gained an average of 3.35 lb (5th to 95th percentile, −4.1 to 12.4). On the basis of increased daily servings of individual dietary components, 4-year weight change was most strongly associated with the intake of potato chips (1.69 lb), potatoes (1.28 lb), sugar-sweetened beverages (1.00 lb), unprocessed red meats (0.95 lb), and processed meats (0.93 lb) and was inversely associated with the intake of vegetables (−0.22 lb), whole grains (−0.37 lb), fruits (−0.49 lb), nuts (−0.57 lb), and yogurt (−0.82 lb) (P≤0.005 for each comparison). Aggregate dietary changes were associated with substantial differences in weight change (3.93 lb across quintiles of dietary change). Other lifestyle factors were also independently associated with weight change (P<0.001), including physical activity (−1.76 lb across quintiles); alcohol use (0.41 lb per drink per day), smoking (new quitters, 5.17 lb; former smokers, 0.14 lb), sleep (more weight gain with <6 or >8 hours of sleep), and television watching (0.31 lb per hour per day). Conclusions: Specific dietary and lifestyle factors are independently associated with long-term weight gain, with a substantial aggregate effect and implications for strategies to prevent obesity.
Kendall C.W., A. Esfahani, A.R. Josse, L.S. Augustin, E. Vidgen, D.J. Jenkins, 2011. The glycemic effect of nut-enriched meals in healthy and diabetic subjects. Nutr. Metab. Cardiovasc. Dis. 21(Suppl 1):S34-9.
BACKGROUND AND AIMS: The intake of nuts has been linked to a reduced risk of cardiovascular disease (CVD) and diabetes in large cohort studies. One potential contributing mechanism may be the ability of nuts to improve post-meal glycemic response. We, therefore, examined the effect of nuts alone and in combination with white bread on postprandial glycemia. METHODS AND RESULTS: 30, 60 and 90 g (approximately 1, 2 and 3 ounces) of mixed nuts were consumed with and without 50 g available carbohydrate from white bread by 10-14 normoglycemic and 5-10 type 2 diabetic subjects. Glycemic response (GR) was assessed by calculating the incremental area under the 2 h blood glucose curve. All three doses of mixed nuts, when fed alone, significantly reduced the glycemic response in both normoglycemic and diabetic patients. Furthermore, in the normoglycemic subjects, adding nuts to white bread progressively reduced the GR of the meal by 11.2 ± 11.6%, 29.7 ± 12.2% and 53.5 ± 8.5% for the 30, 60, and 90 g doses (P = 0.354, P = 0.031 and P < 0.001, respectively), while in subjects with type 2 diabetes, the effect was half of that seen in the non-diabetic subjects (P = 0.474, P = 0.113 and P = 0.015, respectively). CONCLUSION: Nuts alone have little effect on post-meal blood glucose response. Furthermore, when taken with bread, nuts progressively reduce the glycemic response in a dose-dependent manner. While these findings support a short-term benefit for nuts in postprandial glucose response, more studies are required to determine whether these acute benefits result in long-term improvements in glycemic control.
Martínez-González, M.A., M. Bes-Rastrollo, 2011. Nut consumption, weight gain and obesity: Epidemiological evidence. Nutr Metab Cardiovasc Dis. 21(Suppl 1):S40-5.
BACKGROUND AND AIMS: Short-term trials support that adding tree nuts or peanuts to usual diets does not induce weight gain. We reviewed the available epidemiological evidence on long-term nut consumption and body weight changes. We also report new results from the SUN (“Seguimiento Universidad de Navarra”) cohort. METHODS AND RESULTS: Published epidemiologic studies with ≥1-yr follow-up were located. Two published reports from large cohorts (SUN and Nurses Health Study-2) showed inverse associations between frequency of nut consumption and long-term weight changes. A beneficial effect of a Mediterranean diet supplemented with tree nuts on waist circumference was reported after 1-yr follow-up in the first 1224 high-risk participants in the PREDIMED (“PREvencion DIeta MEDiterranea”) trial. After assessing 11,895 participants of the SUN cohort, a borderline significant (p value for trend = 0.09) inverse association between baseline nut consumption and average yearly weight gain (multivariate-adjusted means = 0.32 kg/yr (95% confidence interval: 0.22-0.42) and 0.24 (0.11-0.37) kg/yr for participants with no consumption and >4 servings/week, respectively) was found after a 6-yr follow-up. CONCLUSIONS: Consumption of nuts was not associated with a higher risk of weight gain in long-term epidemiologic studies and clinical trials.
Salas-Salvadó J, Casas-Agustench P, Salas-Huetos A., 2011. Cultural and historical aspects of Mediterranean nuts with emphasis on their attributed healthy and nutritional properties. Nutr Metab Cardiovasc Dis. 21(Suppl 1):S1-6.
BACKGROUND AND AIMS: Nuts have been part of the human diet since prehistoric times. The aim of the present article is to describe the most important historical and cultural aspects of nut consumption throughout history. DATA SYNTHESIS: We discuss the following historical aspects of nuts originating in the Mediterranean: prehistory, the Egyptian civilization, their spread through the Mediterranean region by the Greek, Phoenician and Roman civilizations, and their reintroduction into Europe by means of the Al-Andalus culture. Particular emphasis is placed on the healthy and nutritional attributes that nuts have had throughout history. We also consider the role of the first globalization of food–the exchange of nuts between continents–and discuss the symbolism that nuts have had for humans throughout history in the context of cultural aspects of the Mediterranean region. CONCLUSIONS: Nuts and fruits are probably the earliest foods consumed by humans and are considered to be important because of their nutritional properties. Nuts have also been used in the past by different civilizations as drugs to prevent or treat several diseases.
Kochar, J., J.M. Gaziano, L. Djousse, 2010. Nut consumption and risk of type II diabetes in the Physicians’ Health Study. European Journal of Clinical Nutrition. 64:75–79.
Background/Objectives: While type II diabetes (DM) is a major cause of morbidity in the United States, limited data are available on the association between nut intake and incident DM. We sought to examine the association between nut consumption and the risk of DM. Subjects/Methods: Prospective cohort of 20 224 male participants of the Physicians’ Health Study I. Nut consumption was estimated using a 19-item brief food frequency questionnaire, and incident DM was ascertained through yearly follow-up questionnaires. Cox regression was used to estimate relative risks of DM. Results: The average age of the study participants was 54.4±9.4 years (range: 40.7–87.1). During a mean follow-up of 19.2 years, 1828 cases of DM occurred. The crude incidence rates of DM were 4.82, 4.85, 4.92, 4.16, 4.29 and 3.32 cases per 1000 person-years for individuals reporting nut consumption of rarely/never, <1, 1, 2–4, 5–6 and 7+ servings per week, respectively. While nut consumption was associated with a lower risk of DM in a model adjusted for age (P for tend 0.017), such relation was attenuated on additional control for other confounders (multivariable adjusted hazard ratios (95% confidence interval) for DM were 1.0 (reference), 1.06 (0.93–1.20), 1.10 (0.95–1.26), 0.97 (0.82–1.14), 0.99 (0.76–1.30) and 0.87 (0.61–1.24) from the lowest to the highest category of nut consumption, respectively (P for trend 0.99). No statistically significant association between nut consumption and DM was found in either lean or overweight/obese participants. Conclusions: Our data do not show an association between nut consumption and incident DM in US male physicians.
