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Red meat consumption and risk of type 2 diabetes: 3 cohorts of US adults and an updated meta-analysis.

Pan, A., Q. Sun, A.M. Bernstein, J.E. Manson, W.C. Willett, F.B. Hu, 2011. Red meat consumption and risk of type 2 diabetes: 3 cohorts of US adults and an updated meta-analysis. Am J Clin Nutr.  doi: 10.3945/​ajcn.111.018978.

Background: The relation between consumption of different types of red meats and risk of type 2 diabetes (T2D) remains uncertain. Objective: We evaluated the association between unprocessed and processed red meat consumption and incident T2D in US adults. Design: We followed 37,083 men in the Health Professionals Follow-Up Study (1986–2006), 79,570 women in the Nurses’ Health Study I (1980–2008), and 87,504 women in the Nurses’ Health Study II (1991–2005). Diet was assessed by validated food-frequency questionnaires, and data were updated every 4 y. Incident T2D was confirmed by a validated supplementary questionnaire. Results: During 4,033,322 person-years of follow-up, we documented 13,759 incident T2D cases. After adjustment for age, BMI, and other lifestyle and dietary risk factors, both unprocessed and processed red meat intakes were positively associated with T2D risk in each cohort (all P-trend <0.001). The pooled HRs (95% CIs) for a one serving/d increase in unprocessed, processed, and total red meat consumption were 1.12 (1.08, 1.16), 1.32 (1.25, 1.40), and 1.14 (1.10, 1.18), respectively. The results were confirmed by a meta-analysis (442,101 participants and 28,228 diabetes cases): the RRs (95% CIs) were 1.19 (1.04, 1.37) and 1.51 (1.25, 1.83) for 100 g unprocessed red meat/d and for 50 g processed red meat/d, respectively. We estimated that substitutions of one serving of nuts, low-fat dairy, and whole grains per day for one serving of red meat per day were associated with a 16–35% lower risk of T2D.

Consumption of polyunsaturated fatty acids, fish, and nuts and risk of inflammatory disease mortality.

Gopinath, B., A.E. Buyken, V.M. Flood, M. Empson, E. Rochtchina, P. Mitchell, 2011. Consumption of polyunsaturated fatty acids, fish, and nuts and risk of inflammatory disease mortality. Am J Clin Nutr. 93:1073–9.

Background: n–3 (omega-3) Polyunsaturated fatty acids (PUFAs), fish, and nuts can regulate inflammatory processes and responses. Objective: We investigated whether dietary intakes of PUFAs [n-3, n–6 (omega-6), and α-linolenic acid], fish, and nuts were associated with 15-y mortality attributed to noncardiovascular, noncancer inflammatory diseases. Design: The analyses involved 2514 participants aged ≥49 y at baseline. Dietary data were collected by using a semiquantitative food-frequency questionnaire, and PUFA, fish, and nut intakes were calculated. Inflammatory disease mortality was confirmed from the Australian National Death Index. Results: Over 15 y, 214 subjects died of  inflammatory diseases. Women in the highest tertiles of total n-3 PUFA intake, compared with those in the lowest tertile of intake at baseline, had a 44% reduced risk of inflammatory disease mortality (P for trend = 0.03). This association was not observed in men. In both men and women, each 1-SD increase in energy-adjusted intake of α-linolenic acid was inversely associated with inflammatory mortality (hazard ratio: 0.83; 95% CI: 0.71, 0.98). Subjects in the second and third tertiles of nut consumption had a 51% and 32% reduced risk of inflammatory disease mortality, respectively, compared with those in the first tertile (reference). Dietary intakes of long-chain n-3 and n-6 PUFAs and fish were not associated with inflammatory disease mortality. Conclusions: We report on a novel link between dietary intake of total n-3 PUFA and risk of inflammatory disease mortality in older women. Furthermore, our data indicate a protective role of nuts, but not fish, against inflammatory disease mortality.

Mediterranean nuts: origins, ancient medicinal benefits and symbolism.

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.

Tree nut phytochemicals: composition, antioxidant capacity, bioactivity, impact factors. A systematic review of almonds, Brazils, cashews, hazelnuts, macadamias, pecans, pine nuts, pistachios and walnuts.

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.