Novotny, J.A., S.K. Gebauer, D.J. Baer, 2012. Discrepancy between the Atwater factor predicted and empirically measured energy values of almonds in human diets. Am J Clin Nutr. 96:296–301.
Background: The energy content of foods is primarily determined by the Atwater factors, which may not be accurate for certain food groups. Nuts are a food group for which substantial evidence suggests that the Atwater factors may be poorly predictive. Objective: A study was conducted to determine the energy value of almonds in the human diet and to compare the measured energy value with the value calculated from the Atwater factors. Design: Eighteen healthy adults consumed a controlled diet or an almond-containing diet for 18 d. Three treatments were administered to subjects in a crossover design, and diets contained 1 of 3 almond doses: 0, 42, or 84 g/d. During the final 9 d of the treatment period, volunteers collected all urine and feces, and samples of diets, feces, and urine were analyzed for macronutrient and energy contents. The metabolizable energy content of the almonds was determined. Results: The energy content of almonds in the human diet was found to be 4.6 6 0.8 kcal/g, which is equivalent to 129 kcal/28-g serving. This is significantly less than the energy density of 6.0–6.1 kcal/g as determined by the Atwater factors, which is equivalent to an energy content of 168–170 kcal/serving. The Atwater factors, when applied to almonds, resulted in a 32% overestimation of their measured energy content. Conclusion: This study provides evidence for the inaccuracies of the Atwater factors for certain applications and provides a rigorous method for determining empirically the energy value of individual foods within the context of a mixed diet.
Carey, A.N., S.M. Poulose, B. Shukitt-Hale, 2012. The beneficial effects of tree nuts on the aging brain. Nutrition and Aging. 1:55–67.
Dietary patterns may play an important role in protecting the brain from the cellular and cognitive dysfunction associated with the aging process and neurodegenerative diseases. Tree nuts are showing promise as possible dietary interventions for age-related brain dysfunction. Tree nuts are an important source of essential nutrients, like vitamin E, folate, and fiber. Tree nuts also contain a variety of components, such as phytochemicals like flavonoids, proanthocyanidins, and phenolic acids, as well as monounsaturated and omega-3 and omega-6 polyunsaturated fatty acids that have the potential to combat age-related brain dysfunction. Evidence is accumulating that suggests that tree nuts and their bioactive constituents have the potential to reduce oxidative stress and inflammation, as indicated by decreased lipid peroxidation in vivo and reduced production of the free radical nitric oxide and the pro-inflammatory cytokine tumor necrosis factor-alpha in vitro. Also, tree nut consumption might have the ability to mitigate some of the cognitive decline associated with aging. Here we review the current knowledge of how the consumption of nuts may improve brain health, specifically focusing on walnuts, almonds, pistachios, and pecans.
Dreher, M.L., 2012. Pistachio nuts: composition and potential health benefits. Nutrition Reviews. Vol.70(4):234–240.
The pistachio is a nutrient-dense nut with a heart-healthy fatty-acid profile as well as protein, dietary fiber, potassium, magnesium, vitamin K, γ-tocopherol, and a number of phytochemicals. The pistachio’s unique green and purple kernel color is a result of its lutein and anthocyanin content. Among nuts, pistachios contain the highest levels of potassium, γ-tocopherol, vitamin K, phytosterols, and xanthophyll carotenoids. Five published randomized cardiovascular trials have shown that pistachios promote heart-healthy blood lipid profiles. Exploratory clinical studies suggest that pistachios help maintain healthy antioxidant and anti-inflammatory activity, glycemic control, and endothelial function. When consumed in moderation, pistachios may help control body weight because of their satiety and satiation effects and their reduced net metabolizable energy content. One study with subjects in a weight-loss program demonstrated lower body mass index and triglyceride levels in individuals who consumed pistachios compared with those who consumed an isocaloric pretzel snack. Emerging research suggests that the addition of pistachios to high-glycemic meals may lower the overall postprandial glycemic response. This review examines the nutrients and phytochemicals in pistachios as well as the potential health effects of these nuts.
Carey, A.N., D.R. Fisher, J.A. Joseph, B. Shukitt-Hale, 2012. The ability of walnut extract and fatty acids to protect against the deleterious effects of oxidative stress and inflammation in hippocampal cells. Nutr. Neurosci. doi: 10.1179/1476830512Y.0000000023.
Previous research from our lab has demonstrated that dietary walnut supplementation protects against agerelated cognitive declines in rats; however, the cellular mechanisms by which walnuts and polyunsaturated fatty acids (PUFAs) may affect neuronal health and functioning in aging are undetermined. Objectives: We assessed if pretreatment of primary hippocampal neurons with walnut extract or PUFAs would protect cells against dopamine- and lipopolysaccharide-mediated cell death and calcium dysregulation. Methods: Rat primary hippocampal neurons were pretreated with varying concentrations of walnut extract, linoleic acid, alpha-linolenic acid, eicosapentaenoic acid, or docosahexaenoic acid prior to exposure to either dopamine or lipopolysaccharide. Viability was assessed using the Live/Dead Cellular Viability/Cytotoxicity Kit. Also, the ability of the cells to return to baseline calcium levels after depolarization was measured with fluorescent imaging. Results: Results indicated that walnut extract, alpha-linolenic acid, and docosahexaenoic acid provided significant protection against cell death and calcium dysregulation; the effects were pretreatment concentration dependent and stressor dependent. Linoleic acid and eicosapentaenoic acid were not as effective at protecting hippocampal cells from these insults. Discussion: Walnut extract and omega-3 fatty acids may protect against age-related cellular dysfunction, but not all PUFAs are equivalent in their beneficial effects.
Mandalari, G., T. Genovese, C. Bisignano, E. Mazzon, M.S.J. Wickham, R. Di Paola, G. Bisignano, S. Cuzzocrea, 2011. Neuroprotective effects of almond skins in experimental spinal cord injury. Clinical Nutrition 30:221-233.
Background & Aims: Functional deficits following spinal cord injury (SCI) arise from both mechanical injury and from secondary tissue reactions involving inflammation. Natural almond skins (NS) were tested to evaluate anti-inflammatory effects on an animal model of SCI. Methods: SCI was induced by the application of vascular clips to the dura via a four-level T5-T8 laminectomy. In the present study, to elucidate whether the protective effects of NS are related to the total phenolic content, we also investigated the effect of a blanched (BS) almond skins (industrially obtained by removing bran from the nut) in SCI. NS and BS (30 mg/kg respectively) were administered per os, 1 h and 6 h, after SCI. Results: SCI in mice resulted in severe injury characterized by edema, tissue damage, production of inflammatory mediators and apoptosis (measured by Bax, Bcl-2 and Tunel assay). NS treatment, 1 and 6 h after SCI, reduced all parameters of inflammation as neutrophil infiltration, NF-κB activation, PAR formation, iNOS expression and apoptosis. However, treatment with BS did not exert any protective effect. Conclusions: Our results suggest that NS treatment, reducing the development of inflammation and tissue injury, may be useful in the treatment of SCI.
Mandalari, G., C. Bisignano, T. Genovese, E. Mazzon, M.S.J. Wickham, I. Paterniti, S. Cuzzocrea, 2011. Natural almond skin reduced oxidative stress and inflammation in an experimental model of inflammatory bowel disease. International Immunopharmacology. 11:915–924.
The aim of the present study was to examine the effects of natural almond skin (NS) powder in mice subjected to experimental colitis. Colitis was induced in mice by intracolonic instillation of dinitrobenzene sulfonic acid (DNBS). NS powder was administered daily orally (30 mg/kg). Four days after DNBS administration, colon NF-κB and p-JNK activation was increased as well as TNF-α and IL-1β productions. Neutrophil infiltration, by myeloperoxidase (MPO) activity, in the mucosa was associated with up-regulation of ICAM-1 and P-selectin. Immunohistochemistry for i-NOS, nitrotyrosine and poly (ADP-ribose) polymerase (PARP) showed an intense staining in the inflamed colon. Treatment with NS powder significantly reduced the appearance of diarrhea and body weight loss. This was associated with a significant reduction in colonic MPO activity. NS powder also reduced NF-κB and p-JNK activation, the pro-inflammatory cytokines release, the appearance of i-NOS, nitrotyrosine and PARP in the colon and reduced the up-regulation of ICAM-1 and the expression of P-selectin. The results of this study suggested that administration of NS powder may be beneficial for treatment of inflammatory bowel disease.
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.
Yada, S., K. Lapsley, G. Huang, 2011. A review of composition studies of cultivated almonds: Macronutrients and micronutrients. Journal of Food Composition and Analysis. 24:469–480.
Prunus dulcis, the cultivated sweet almond, has long been recognized as a source of nutrients in many traditional diets, and is increasingly promoted as a healthy snack and ingredient. This paper reviews the global research over the past 50 years that has contributed to knowledge on the composition and characterization of almond macronutrients and micronutrients, specifically the lipids and fatty acids, proteins and amino acids, carbohydrates (including dietary fiber), minerals and vitamins. Tables providing an overview of major macronutrient and micronutrient contents (range of means per 100 g) as reported for almonds grown in various production regions are presented. Considerable variability in lipid content has been reported within and among commercial varieties and breeding selections; total lipids range from 25 to 66 g/100 g almonds (fresh weight). Oleic and linoleic acids account for about 90% of total lipids, and saturated fatty acid levels are very low (<10%) in all varieties from all regions. However, oleic/linoleic acid ratios vary widely among varieties. Total protein contents range from 14 to 26 g/100 g almonds. α-Tocopherol is the major vitamin E isomer in all almond varieties assessed; β-, γ- and δ-tocopherols are minor components. Published data on total dietary fiber (TDF), minerals and other vitamins in almonds are limited.
Del Rio, D., L. Calani, M. Dall’Asta, F. Brighenti, 2011. Polyphenolic composition of hazelnut skin. J Agric Food Chem. 59(18):9935-9941.
Skins from different hazelnut samples were characterized for total polyphenol content, total antioxidant capacity (TAC), and their content in specific polyphenolic compounds. The main polyphenolic subclass, identified and quantified by means of HPLC-MS/MS, comprised monomeric and oligomeric flavan-3-ols, which accounted for more than 95% of total polyphenols. Flavonols and dihydrochalcones were 3.5% while phenolic acids were less than 1% of the total identified phenolics. The TAC values of the skin samples ranged between 0.6 and 2.2 mol of reduced iron/kg of sample, which is about 3 times the TAC of whole walnuts, 7-8 times that of dark chocolate, 10 times that of espresso coffee, and 25 times that of blackberries. By describing the profile of polyphenols present in hazelnut skins, this study provides the basis to further investigate the potential health effects of hazelnut byproduct.
V. Schmitzer, A. Slatnar, R. Veberic, F. Stampar, A. Solar, 2011. Roasting affects phenolic composition and antioxidative activity of hazelnuts (Corylus avellana L.) J Food Sci. 76(1):S14-9. doi: 10.1111/j.1750-3841.2010.01898.x.
The potential effect of skin removal and roasting on individual and total phenolic content, and on antioxidative potential of 6 hazelnut cultivars were investigated. HPLC-MS identification of individual phenolics confirmed the presence of 7 flavan-3-ols (catechin, epicatechin, 2 procyanidin dimers, and 3 procyanidin trimers), 3 flavonols (quercetin pentoside, quercetin-3-O-rhamnoside, and myricetin-3-O-rhamnoside), 2 hydrobenzoic acids (gallic acid, protocatechulic acid), and 1 dihydrochalcone (phloretin-2′-O-glucoside). Flavonols were only detected in whole hazelnut kernels. The content of individual phenolics, with the exception of gallic acid, was always highest in whole unroasted hazelnuts and was significantly reduced after skin removal. Similarly, total phenolic content and antioxidative potential decreased when skin was removed. Roasting had a significant negative effect on individual phenolics but not on the total phenolic content and antioxidative potential of kernels. From a health promoting phytochemical composition of hazelnuts the consumption of whole unroasted kernels with skins should be preferential to peeled kernels either roasted or unroasted. Practical Application: A significant reduction in the antioxidative potential and total phenolic content is detected after hazelnut skin removal but not after roasting, suggesting that hazelnut kernels should be consumed whole. In hazelnut skin, many phenolic compounds are located, which are not present in flesh and, therefore, the health properties of hazelnuts are strongly affected by skin removal. Thermal processing and roasting conditions used in this study had a lesser effect on the individual phenolic composition of the kernel and thus roasted and unroasted hazelnuts without skin contain comparable amounts of health promoting compounds.
