(The studies are listed in alphabetical order by last name of the first author.)

For more research on the health benefits of nuts in general, visit nuthealth.org

Aksoy N, Aksoy M, Bagci C, Gergerlioglu HS, Celik H, Herken E, Yaman A, Tarakcioglu M, Soydinc S, Sari I, Davutoglu V. 2007. Pistachio intake increases high-density lipoprotein levels and inhibits low-density lipoprotein oxidation in rats. Tohoku J Exp Med. May;212(1):43-8. There is increasing evidence that nuts have protective effects against coronary artery disease by improving lipid profile and inhibiting lipid oxidation. However, data about pistachio nuts are limited, and to our knowledge, there is no study investigating the effects of pistachio intake on lipid oxidation and serum antioxidant levels. This study, therefore, sought to determine the effects of pistachio intake on serum lipids and determine whether consumption of pistachio would alter serum antioxidant levels. Rats were randomly divided into three groups (n=12 for each): control group fed basic diet for 10 weeks and treated groups fed basic diet plus pistachio, which constituted 20% and 40% of daily caloric intake, respectively. Consumption of pistachio as 20% of daily caloric intake increased high-density lipoprotein (HDL) levels and decreased total cholesterol (TC)/HDL ratio, compared with those not taking pistachio. However, TC, low-density lipoprotein (LDL) cholesterol and triglyceride levels were unaffected by pistachio consumption. Consumption of pistachio as 20% of daily caloric intake increased serum paraoxonase activity by 35% and arylesterase activity by 60%, which are known to inhibit LDL cholesterol oxidation, compared with the control group. However, increased antioxidant activity was blunted when pistachio intake was increased to 40% of daily caloric intake. In conclusion, the present results show that consumption of pistachio as 20% of daily caloric intake leads to significant improvement in HDL and TC/HDL ratio and inhibits LDL cholesterol oxidation. These results suggest that pistachio may be beneficial for both prevention and treatment of coronary artery disease.

Aldemir M, Okulu E, Neşelioğlu S, Erel O, Kayıgil O, 2011. Pistachio diet improves erectile function parameters and serum lipid profiles in patients with erectile dysfunction. Int J Impot Res. 23(1):32-8. We investigated the effects of Antep pistachio on International Index of Erectile Function (IIEF) scores, penile color Doppler ultrasound (PCDU) parameters and serum lipid levels in patients with ED. A total of 17 married male patients with ED for at least 12 months were included in this prospective study. Patients were put on a 100–g pistachio nuts diet for 3 weeks. IIEF and PCDU were evaluated before and after the pistachio diet. In addition, plasma total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL) and triglyceride were measured before and after dietary modifications from all subjects. Mean IIEF-15 score was 36 ± 7.5 before the diet and 54.2 ± 4.9 after the diet (P=0.001). Similarly, an increase in all five domains of IIEF was observed after the diet (P

Alasalvar C and Shahidi F. Natural antioxidants in tree nuts. 2009. Eur. J. Lipid Sci. Technol., 111: 1056–1062. The levels of natural antioxidants and phytochemicals present in tree nuts are reported. Where possible, the health claims by Food and Drug Administration and European Food Safety Authority and health effects of tree nuts are provided. The content and recommended dietary allowances of nutrient antioxidants (such as vitamins A, C, E, and the mineral selenium) present in various tree nuts are compared. Antioxidant activity and phytochemicals present among tree nuts have been thoroughly reviewed. Research findings from over 65 references, many of which have been published within the last 10 years, have been compiled and reported.

Ando K, Watanabe D, Tamada Y, Matsumoto Y. 2011. Oral allergy syndrome with severe anaphylaxis induced by pistachio. Int J Dermatol. May;50(5):632-3. (correspondence)

Baer DJ, Gebauer SK, Novotny JA. 2011. Measured energy value of pistachios in the human diet. Br J Nutr. Jun 28:1-6. Previous studies have suggested that lipid from nuts is more poorly absorbed than that from other food sources. If lipid from nuts is poorly absorbed, then the metabolizable energy contained in the nuts is less than that predicted by the Atwater general factors. A crossover feeding study was conducted in which sixteen volunteers consumed pistachios for 3 weeks as part of a controlled diet. Pistachio doses were 0, 42 and 84 g/d. Urine and faecal samples were collected, and urine, faeces and diet were analyzed for N, fat, total dietary fibre, ash and combustible energy. Blood was also collected after each treatment period and analyzed for plasma lipids. Energy value of pistachio nuts was calculated from differences in energy excretion during the different dietary treatments. The measured energy density of pistachios was found to be 22·6 kJ/g, which is 5% less than the currently accepted energy value of 23·7 kJ/g, as calculated using the Atwater general factors. The pistachio nut intervention lowered LDL cholesterol by 6%, but did not significantly change plasma total cholesterol, HDL cholesterol or TAG. In conclusion, pistachio nuts contain less metabolizable energy than that calculated from the Atwater general factors. Accurate information about metabolizable energy content of foods is important for reliable food labeling.

Bes-Rastrollo M, Wedick NM, Martinez-Gonzalez MA, Li TY, Sampson L, Hu FB. 2009. Prospective study of nut consumption, long-term weight change, and obesity risk in women. Am J Clin Nutr. Jun;89(6):1913-9. BACKGROUND: Data concerning the long-term association between nut consumption and weight change in a free-living population are sparse. OBJECTIVE: The objective was to determine the relation between nut consumption and long-term weight change. DESIGN: The participants were 51,188 women in the Nurses' Health Study II aged 20-45 y, who had no cardiovascular disease, diabetes, or cancer. We prospectively evaluated the dietary intake of nuts and subsequent weight changes from 1991 to 1999. RESULTS: Women who reported eating nuts > or =2 times/wk had slightly less mean (+/- SE) weight gain (5.04 +/- 0.12 kg) than did women who rarely ate nuts (5.55 +/- 0.04 kg) (P for trend or =2 times/wk). The results were similar in normal-weight, overweight, and obese participants. In multivariate analyses in which lifestyle and other dietary factors were controlled for, we found that greater nut consumption (> or =2 times/wk compared with never/almost never) was associated with a slightly lower risk of obesity (hazard ratio: 0.77; 95% CI: 0.57, 1.02; P for trend = 0.003). CONCLUSIONS: Higher nut consumption was not associated with greater body weight gain during 8 y of follow-up in healthy middle-aged women. Instead, it was associated with a slightly lower risk of weight gain and obesity. The results of this study suggest that incorporating nuts into diets does not lead to greater weight gain and may help weight control.

Bolling BW, McKay DL, Blumberg JB. 2010. The phytochemical composition and antioxidant actions of tree nuts. Asia Pac J Clin Nutr.19(1):117-23. In addition to being a rich source of several essential vitamins and minerals, mono- and polyunsaturated fatty acids, and fiber, most tree nuts provide an array of phytochemicals that may contribute to the health benefits attributed to this whole food. Although many of these constituents remain to be fully identified and characterized, broad classes include the carotenoids, hydrolyzable tannins, lignans, naphthoquinones, phenolic acids, phytosterols, polyphenols, and tocopherols. These phytochemicals have been shown to possess a range of bioactivity, including antioxidant, antiproliferative, anti-inflammatory, antiviral, and hypocholesterolemic properties. This review summarizes the current knowledge of the carotenoid, phenolic, and tocopherol content of tree nuts and associated studies of their antioxidant actions in vitro and in human studies. Tree nuts are a rich source of tocopherols and total phenols and contain a wide variety of flavonoids and proanthocyanidins. In contrast, most tree nuts are not good dietary sources of carotenoids and stilbenes. Phenolic acids are present in tree nuts but a systematic survey of the content and profile of these compounds is lacking. A limited number of human studies indicate these nut phytochemicals are bioaccessible and bioavailable and have antioxidant actions in vivo.

Casas-Agustench P, López-Uriarte P, Ros E, Bulló M, Salas-Salvad J. 2011. Nuts, hypertension and endothelial function. Nutr. Metab. Cardiovasc. Dis. 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.

Chen O and Blumberg J. 2008. Phytochemical composition of nuts. Asia Pac J Clin Nutr. 7 (S1):329-332 Observational studies suggest nut consumption is inversely associated with the incidence of cardiovascular disease and cancer. In addition to being rich in several vitamins and minerals, unsaturated fatty acids and fiber, tree nuts and peanuts contain numerous phytochemicals that may contribute to promoting health and reducing the risk of chronic disease. While many of these bioactive constituents remain to be fully identified and characterized, broad classes include carotenoids, phenols, and phytosterols. Phytosterols in nuts range from 95-280 mg/100 g. a- and ß-Carotene, ß-cryptoxanthin, lutein, and zeaxanthin are found in µg/100 g amounts in some nuts but at 1-3 mg/100 g in pistachios and none at all in Brazils, macadamias, and peanuts. Phenols, including phenolic acids, flavonoids, and stilbenes, are present in nuts. Walnuts are particularly rich in total phenols with 1625 mg gallic acid equivalents/100 g. The stilbene resveratrol is found in peanuts and pistachios at 84 and 115 µg/100 g, respectively. The flavonoid content of nuts as provided in USDA Database for the Flavonoid Content of Selected Foods, lists totals in pecans at 34, almonds at 15, and pistachios and hazelnuts at 12 mg/100 g. Proanthocyanidins are found in almonds, cashews, hazelnuts, pecans, pistachios, peanuts, and walnuts, with concentrations varying from 9-494 mg/100 g. Nut phytochemicals have been associated with numerous bioactivities known to affect the initiation and progression of several pathogenic processes. However, as complete phytochemical profiles are lacking for most nuts, information is limited regarding regarding their bioavailability and metabolism, so further research on this topic is warranted.
Edwards K, Kwaw I, Matud J, Kurtz I. 1999. Effect of pistachio nuts on serum lipid levels in patients with moderate hypercholesterolemia. J Am Coll Nutr. 18(3):229-32. BACKGROUND: Elevated serum cholesterol levels play an important role in the development of coronary artery disease. Previous studies have suggested that nut consumption benefits lipid profile. Pistachio nuts are widely available, inexpensive and frequently consumed by the general population. OBJECTIVE: To determine whether substituting 20% of the daily caloric intake in the form of pistachio nuts will improve the lipid profiles of humans with primary, moderate hypercholesterolemia. DESIGN: Controlled, randomized crossover design. SETTING: Outpatient dietary modification, counseling and blood analysis. PATIENTS: Ten patients with moderate hypercholesterolemia. INTERVENTION: Three weeks of dietary modification with 20% caloric intake from pistachio nuts. MEASUREMENTS: Body weight, blood pressure, total cholesterol, LDL, HDL, and triglycerides were monitored. Lipid profiles were analyzed prior to, during and after dietary modification. RESULTS: After three weeks, there was a decrease in total cholesterol (p

Gebauer SK, West SG, Kay CD, Alaupovic P, Bagshaw D, Kris-Etherton PM. 2008. Effects of pistachios on cardiovascular risk factors and potential mechanisms of action: A dose-response study. Am J Clin Nutr. 88:651-9. BACKGROUND: Nut consumption lowers cardiovascular disease (CVD) risk. Studies are lacking about the effects of pistachios, a nutrient-dense nut, on CVD risk factors, dose-response relations, and lipid-lowering mechanisms. OBJECTIVE: We evaluated the effects of 2 doses of pistachios, added to a lower-fat diet, on lipids and lipoproteins, apolipoprotein (apo)-defined lipoprotein subclasses, and plasma fatty acids. To investigate the mechanisms of action, we measured cholesteryl ester transfer protein and indexes of plasma stearoyl-CoA desaturase activity (SCD). DESIGN: In a randomized crossover controlled-feeding study, 28 individuals with LDL cholesterol ≥ 2.86 mmol/L consumed 3 isoenergetic diets for 4 wk each. Baseline measures were assessed after 2 wk of a typical Western diet. The experimental diets included a lower-fat control diet with no pistachios [25% total fat; 8% saturated fatty acids (SFAs), 9% monounsaturated fatty acids (MUFAs), and 5% polyunsaturated fatty acids (PUFAs)], 1 serving/d of a pistachio diet (1 PD; 10% of energy from pistachios; 30% total fat; 8% SFAs, 12% MUFAs, and 6% PUFAs), and 2 servings/d of a pistachio diet (2 PD; 20% of energy from pistachios; 34% total fat; 8% SFAs, 15% MUFAs, and 8% PUFAs). RESULTS: The 2 PD decreased (P

Gentile C, Allegra M, Angileri F, Pintaudi AM, Livrea MA, Tesoriere L. 2011. Polymeric proanthocyanidins from Sicilian pistachio (Pistacia vera L.) nut extract inhibit lipopolysaccharide-induced inflammatory response in RAW 264.7 cells. Eur J Nutr. Jul 7.BACKGROUND: Positive effects of pistachio nut consumption on plasma inflammatory biomarkers have been described; however, little is known about molecular events associated with these effects. PURPOSE: We studied the anti-inflammatory activity of a hydrophilic extract from Sicilian Pistacia L. (HPE) in a macrophage model and investigated bioactive components relevant to the observed effects. METHODS: HPE oligomer/polymer proanthocyanidin fractions were isolated by adsorbance chromatography, and components quantified as anthocyanidins after acidichydrolysis. Isoflavones were measured by gradient elution HPLC analysis. RAW264.7 murine macrophages were pre-incubated with either HPE (1- to 20-mg fresh nut equivalents) or its isolated components for 1 h, then washed before stimulating with lipopolysaccharide (LPS) for 24 h. Cell viability and parameters associated with Nuclear Factor-κB (NF-κB) activation were assayed according to established methods including ELISA, Western blot, or cytofluorimetric analysis. RESULTS: HPE suppressed nitric oxide (NO) and tumor necrosis factor-α (TNF-α) production and inducible NO-synthase levels dose dependently, whereas inhibited prostaglandin E(2) (PGE(2)) release and decreased cyclo-oxygenase-2 content, the lower the HPE amount the higher the effect. Cytotoxic effects were not observed. HPE also caused a dose-dependent decrease in intracellular reactive oxygen species and interfered with the NF-κB activation. Polymeric proanthocyanidins, but not isoflavones, at a concentration comparable with their content in HPE, inhibited NO, PGE(2), and TNF-α formation, as well as activation of IκB-α. Oligomeric proanthocyanidins showed only minor effects. CONCLUSIONS: Our results provide molecular evidence of anti-inflammatory activity of pistachio nut and indicate polymeric proanthocyanidins as the bioactive components. The mechanism may involve the redox-sensitive transcription factor NF-κB. Potential effects associated with pistachio nut consumption are discussed in terms of the proanthocyanidin bioavailability.heir bioavailability and metabolism, so further research on this topic is warranted.

Hasegawa M, Inomata N, Yamazaki H, Morita A, Kirino M, Ikezawa Z. 2009. Clinical features of four cases with cashew nut allergy and cross-reactivity between cashew nut and pistachio. Allergol Int. Jun;58(2):209-15. BACKGROUND: Few cases of cashew nut (CN) allergy have been reported in Japan. We evaluated the clinical features of 4 cases with CN allergy and investigated the allergens involved. METHODS: In order to investigate the cross-reactivity between CN and pistachios, we performed ImmunoCAP inhibition tests using sera of 4 cases with positive histories of CN allergy and positive results of specific IgE measurement (ImmunoCAP) and skin prick tests. Furthermore, we analyzed the molecular weights of allergens of CN and pistachios by IgE-immunoblotting. RESULTS: Of the 4 cases (male : female = 1:3), there were 3 cases (patient #2-4) and 1 case (patient #1) of anaphylaxis and oral allergy syndrome, respectively.The initial symptom was an oropharyngeal symptom in 3 of the 4 cases, of which 2 cases developed anaphylaxis within 10 minutes after eating only a few pieces of CN. All 4 cases reacted positively to the skin prick test with CN, although 1 case of anaphylaxis tested negatively for CN by ImmunoCAP. Additionally, in 2 cases, IgE-binding to CN and pistachio were inhibited with both pistachios and CN, indicating cross-reactivity between CN and pistachios. IgE-immunoblotting of CN using sera from the 4 cases revealed 2 bands at molecular weights of approximately 33 kd and 42 kd, whereas that of pistachios showed a single band at 36 kd. However, IgE in all 4 sera did not bind to rAna o 2. CONCLUSIONS: In CN allergy, a small amount of CN could induce a severe anaphylactic reaction. Moreover, in cases of suspected CN allergy, reactions to not only CN but also pistachio, which could be cross-reactive to CN, should be examined.

Honselman CS, Painter JE, Kennedy-Hagan KJ, Halvorson A, Rhodes K, Brooks TL,Skwir K. 2011. In-shell pistachio nuts reduce caloric intake compared to shelled nuts. Appetite. Oct;57(2):414-7. It was hypothesized that consuming in-shell pistachios, compared to shelled pistachios, causes individuals to consume less. A convenience sample of students at a mid-western university (n=140) was recruited, asking them to evaluate a variety of brands of pistachios. A survey at the end of class determined fullness and satisfaction. Subjects entering the classroom were given a 16-ounce cup and asked to self-select a portion of pistachios. Portion weight was recorded and subjects consumed pistachios at their leisure during class. At class end, pistachios remaining in the cup were weighed and total consumption by weight was determined. The caloric content of each portion was then calculated. In condition one, subjects offered in-shell pistachios consumed an average of 125 calories. In condition two, subjects offered shelled pistachios consumed an average of 211 calories – a difference of 86 calories. Subjects in condition one consumed 41% fewer calories compared to subjects in condition two (p≤.01). Fullness and satisfaction ratings were not significantly different (p≥.01). Caloric intake was influenced by the initial form of the food. The difference in calories consumed may be due to the additional time needed to shell the nuts or the extra volume perceived when consuming in-shell nuts.

Jenab M, Ferrari P, Slimani N, Norat T, Casagrande C, Overad K, Olsen A, Stripp C, Tjønneland A, Boutron-Ruault MC, Clavel-Chapelon F, Kesse E, Nieters A, Bergmann M, Boeing H, Naska A, Trichopoulou A, Palli D, Krogh V, Celentano E, Tumino R, Sacerdote C, Bueno-de-Mesquita HB, Ocké MC, Peeters PH, Engeset D, Quirós JR, González CA, Martínez C, Chirlaque MD, Ardanaz E, Dorronsoro M, Wallström P, Palmqvist R, Van Guelpen B, Bingham S, San Joaquin MA, Saracci R, Kaaks R, Riboli E. 2004. Association of nut and seed intake with colorectal cancer risk in the European Prospective Investigation into Cancer and Nutrition. Cancer Epidemiol Biomarkers Prev. Oct;13(10):1595-603. A link between unsaturated fatty acids or phytonutrients and reduced risk of colorectal cancer has been suggested. However, the effects of higher intake of dietary sources of these nutrients, such as the nuts and seeds food group, are less clear. The objective of this study was to determine the effects of nut and seed intake on colorectal cancer risk within the European Prospective Investigation into Cancer and Nutrition study, a large prospective cohort study involving 10 European countries. Total nut and seed intake was determined from country-specific dietary questionnaires. The data set included 478,040 subjects (141,988 men, 336,052 women) with a total of 855 (327 men, 528 women) colon and 474 (215 men, 259 women) rectal cancer cases. A multivariate Cox proportional hazards model, stratified by center and controlled for fruit intake, dietary fiber, energy, height, weight, sex, age, physical activity, and smoking, was used. The data show no association between higher intake of nuts and seeds and risk of colorectal, colon, and rectal cancers in men and women combined, but a significant inverse association was observed in subgroup analyses for colon cancer in women at the highest (>6.2 g/d) versus the lowest (nonconsumers; hazard ratio, 0.69; 95% confidence interval, 0.50-0.95) category of intake and for the linear effect of log-transformed intake (hazard ratio, 0.89; 95% confidence interval, 0.80-0.98), with no associations in men. It is not evident from this data why there may be a stronger association in women or why it may be limited to the colon, suggesting that much further research is necessary.

Jenkins DJA, Kendall CWC, Banach MS, Srichaikul K, Vidgen E, Mitchell S, TParker T, Nishi S, Bashyam B, de Souza R, Ireland C, Josse RG. 2011. Nuts as a replacement for carbohydrates in the diabetic diet. Diabetes Care. 34:1-6. 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

Kay CD, Gebauer SK, West SG, Kris-Etherton PM. 2010. Pistachios increase serum antioxidants and lower serum oxidized-LDL in hypercholesterolemic adults. J Nutr. Jun;140(6):1093-8. Pistachios are high in lutein, beta-carotene, and gamma-tocopherol relative to other nuts; however, studies of the effects of pistachios on oxidative status are lacking. We conducted a randomized, crossover controlled-feeding study to evaluate 2 doses of pistachios on serum antioxidants and biomarkers of oxidative status in 28 hypercholesterolemic adults (LDL-cholesterol >or=2.86 mmol/L). Participants consumed 3 isoenergetic diets for 4 wk each after a 2-wk baseline Western diet. Experimental diets included a lower-fat control diet without pistachios (25% total fat) with 1 serving/d (i.e. 32-63 g/d; energy adjusted) of pistachios (1 PD; 10% energy from pistachios; 30% total fat) or with 2 servings/d (63-126 g/d; energy adjusted) of pistachios (2 PD; 20% energy from pistachios; 34% total fat). When participants consumed the pistachio-enriched diets, they had higher plasma lutein (P

Kendall CW, Josse AR, Esfahani A, Jenkins DJ. 2011. The impact of pistachio intake alone or in combination with high-carbohydrate foods on post-prandial glycemia. Eur J Clin Nutr. 65(6):696-702. BACKGROUND/OBJECTIVES: Dietary strategies that reduce post-prandial glycemia are important in the prevention and treatment of diabetes and coronary heart disease (CHD). This may be achieved by addition of high-quality protein and fat contained in pistachio nuts, to carbohydrate-containing foods or meals. SUBJECTS/METHODS: A total of 10 healthy volunteers (3 males, 7 females); aged 48.3±6.4 years; Body mass index (BMI) 28.0±4.8 kg/m(2) participated in two studies. Study 1 assessed the dose-response effect of 28, 56 and 84 g pistachios consumed alone or co-ingested with white bread (50 g available carbohydrate); Study 2 assessed the effective dose (56 g) of pistachios on post-prandial glycemia consumed with different commonly consumed carbohydrate foods (50 g available carbohydrate). Relative glycemic responses (RGRs) of study meals compared with white bread, were assessed over the 2 h post-prandial period. RESULTS:The RGRs of pistachios consumed alone expressed as a percentage of white bread (100%) were: 28 g (5.7±1.8%); 56 g (3.8±1.8%); 84 g (9.3±3.2%), P

Kendall CW, Esfahani A, Truan J, Srichaikul K, Jenkins DJ. 2010. Health benefits of nuts in prevention and management of diabetes. Asia Pac J Clin Nutr. 19(1):110-6. The effects of tree nuts on risk factors for coronary heart disease (CHD), in particular blood lipids, have been investigated in a number of studies and the beneficial effects are now recognized. The beneficial effects of nuts on CHD in cohort studies have also been clearly demonstrated. However, while there is also reason to believe the unique micro- and macronutrient profiles of nuts may help to control blood glucose levels, relatively few studies have investigated their role in diabetes control and prevention. Nuts are low in available carbohydrate, have a healthy fatty acid profile, and are high in vegetable protein, fiber and magnesium. Acute feeding studies indicate that when eaten alone nuts have minimal effects on raising postprandial blood glucose levels. In addition, when nuts are consumed with carbohydrate rich foods, they blunt the postprandial glycemic response of the carbohydrate meal. Despite the success of these acute studies, only a limited number of trials have been conducted with nuts in type 2 diabetes. These studies have either been of insufficient duration to observe changes in HbA1c, as the standard measure of glycemic control, or have been underpowered. Therefore, more long-term clinical trials are required to examine the role of nuts on glycemic control in patients with prediabetes and diabetes. Overall, there are good reasons to justify further exploration of the use of nuts in the prevention of diabetes and its micro- and macrovascular complications.

Kendall CW, Josse AR, Esfahani A, Jenkins DJ. 2010. Nuts, metabolic syndrome and diabetes. Br J Nutr. Aug;104(4):465-73. The ability of nuts to improve the blood lipid profile and reduce the risk of CHD is now well established. The interest that health effects of nuts have gained recently has brought the possible benefits of consuming nuts, such as improvement in the conditions of the metabolic syndrome, and their potential to prevent and control diabetes into focus. Results from cohort studies have associated nut consumption with a reduced risk of developing diabetes and CVD. However, few randomised controlled trials have assessed the effect of nuts on diabetes control, and those that have been undertaken have shown improvements in blood lipids but not in the glycaemic control. Diabetes agencies are increasingly recognizing the importance of controlling postprandial glycaemia fluctuations. Acute feeding studies indicate that nuts have minimal effects on rising postprandial blood glucose levels when eaten alone, and diminish the postprandial glycaemic response when consumed with high-glycaemic index carbohydrate foods in both normoglycaemic and type 2 diabetic individuals. Nuts have a healthy nutritional profile, high in MUFA and PUFA, are a good source of vegetable protein and are rich in fiber, vitamins and minerals. Incorporation of nuts in the diet may therefore improve the overall nutritional quality of the diet. While more research is required to establish the ability of nuts to improve glycaemic control in the long run, early data indicate that the inclusion of nuts in the diets of individuals with diabetes and the metabolic syndrome is warranted, in view of their potential to reduce CHD risk.

Kennedy-Hagan K., Painter JE, Honselman C, Halvorson A, Rhodes K, Skwir K, 2011. The effect of pistachio shells as a visual cue in reducing caloric consumption. Appetite. Oct;57(2):418-20. It was hypothesized that pistachio shells left in sight as visual cues of consumption will cause individuals to consume less. A convenience sample of faculty and staff at a mid-western university (n=118) were recruited as subjects for the study. The subjects were told they were going to evaluate a variety of brands of pistachios and were surveyed at the end of each day to determine their fullness and satisfaction. The subjects were offered pistachios on their desks for an 8-h period on two separate days and were able to consume the pistachios at their leisure during that time. Subjects began each day with a sixteen ounce bowl filled with four ounces of pistachios in the shell. They were also provided with a second sixteen ounce bowl, in which they were instructed to place the empty shells from the pistachios they consumed. Every 2h throughout the day pistachios were added in two ounce increments. In condition one, the shells remained in the bowls until the end of the day, whereas in condition two, the shell bowls were emptied every 2h throughout the day. In condition one, subjects consumed an average of 216 calories. In condition two, subjects consumed an average of 264 calories, a difference of 48 calories. Subjects in condition one consumed significantly (p≤.05) fewer calories, yet fullness and satisfaction ratings were not significantly (p≥.05) different between conditions. Leaving pistachio shells as a visual cue to consumption may help consumers consume fewer calories. Learning outcomes: Individuals will be aware of the impact of visual cues of dietary intake on total food consumption.

Kocyigit A, Koylu AA, Keles H. 2006. Effects of pistachio nuts consumption on plasma lipid profile and oxidative status in healthy volunteers. Nutrition, Metabolism & Cardiovascular Diseases. 16:202-9. BACKGROUND AND AIM: Effects of pistachio nuts consumption on plasma lipid profile and oxidative status were investigated in healthy volunteers with normal lipid levels. Methods and results: The study was conducted in 24 healthy men and 20 healthy women. All subjects consumed their regular diets during a 1 week period. After this period, half of the subjects (12 men and 10 women, mean age 32.8 ± 6.7 years) were randomized to a regular diet group and the other half (12 men and 10 women, mean age 33.4 ± 7.2 years) were randomized to a pistachio group which involved substituting pistachio nuts for 20% of their daily caloric intake for 3 weeks. Plasma total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglyceride, malondialdehyde (MDA) and antioxidant potential (AOP) were measured before and after the dietary modification from all the subjects. After 3 weeks, with the pistachio diet, the mean plasma total cholesterol, MDA levels and, total cholesterol/ HDL and LDL/HDL ratios were found to be significantly decreased (P 0.05). CONCLUSION: These results indicated that consumption of pistachio nuts decreased oxidative stress, and improved total cholesterol and HDL levels in healthy volunteers

Li Z, Song R, Nguyen C, Zerlin A, Karp H, Naowamondhol K, Thames G, Gao K, Li L, Tseng CH, Henning SM, Heber D. 2010. Pistachio nuts reduce triglycerides and body weight by comparison to refined carbohydrate snack in obese subjects on a 12-week weight loss program. J Am Coll Nutr. 29(3):198-203. OBJECTIVE: There is a widely held view that, due to high fat content, snacking on nuts will lead to weight gain, ultimately causing unhealthy changes in lipid profiles. This study is designed to study the effects of pistachio snack consumption on body weight and lipid levels in obese participants under real-world conditions. METHODS: Participants were randomly assigned to consume 1 of 2 isocaloric weight reduction diets for 12 weeks, with each providing 500 cal per day less than resting metabolic rate. Each diet included an afternoon snack of either 53 g (240 cal) of salted pistachios (n  =  31) or 56 g of salted pretzels (220 cal; n  =  28). RESULTS: Both groups lost weight during the 12-week study (time trend, p

Mattes RD, Dreher ML. 2010. Nuts and healthy body weight maintenance mechanisms. Asia Pac J Clin Nutr. 19(1):137-41. Nuts are rich sources of multiple nutrients and phytochemicals associated with health benefits, including reduced cardiovascular disease risk. This has prompted recommendations to increase their consumption. However, they are also high in fat and are energy dense. The associations between these properties, positive energy balance and body weight raise questions about such recommendations. Numerous epidemiological and clinical studies show that nuts are not associated with weight gain. Mechanistic studies indicate this is largely attributable to the high satiety and low metabolizable energy (poor bioaccessibility leading to inefficient energy absorption) properties of nuts. Compensatory dietary responses account for 55-75% of the energy provided by nuts. Limited data suggest that routine nut consumption is associated with elevated resting energy expenditure and the thermogenic effect of feeding, resulting in dissipation of another portion of the energy they provide. Additionally, trials contrasting weight loss through regimens that include or exclude nuts indicate improved compliance and greater weight loss when nuts are permitted. Nuts may be included in the diet, in moderation, to enhance palatability, nutrient quality, and chronic disease risk reduction without compromising weight loss or maintenance.

Noorbakhsh R, Mortazavi SA, Sankian M, Shahidi F, Tehrani M, Jabbari Azad F, Behmanesh F, Varasteh A. 2011. Pistachio allergy-prevalence and in vitro cross-reactivity with other nuts. Allergol Int. May 25. Background: Tree nut allergy is characterized by a high frequency of life-threatening reactions and is typically lifelong persistent. Some people with a pistachio nut allergy, which is common in the pistachio rich area of Iran, develop a hypersensitivity to other tree nuts as well. The aim of this study was to investigate the prevalence of pistachio nut allergy in Iran, the major pistachio cultivation region in the world. The study also addressed the presence of allergenic cross-reactivity between pistachio and other nuts, including almond, peanut, and cashew in pistachio allergic patients. Methods: A survey was conducted to determine whether the prevalence of pistachio allergy is affected by exposure to this nut in pistachio cultivation regions, as well as possible cross-reactivity between pistachio and other nuts including cashew, almond, and peanut. Inhibition Western blot and inhibition ELISA studies were conducted to assess the presence of allergenic cross-reactivity between pistachio and the other tree nuts. Results: Our results revealed that the prevalence of pistachio allergy is twice as much in pistachio cultivation regions than other areas. Western blotting and inhibition ELISA presented high percentages of inhibition with pistachio and cashew, followed by almond and, to some degree, peanut which indicates different levels of allergenic cross-reactivity. Conclusions: The results indicate that exposure of people to pistachio significantly affects the prevalence of its allergic reactions. In addition, it was observed that, among pistachio allergic subjects, such exposure may affect the co-sensitivities with other nuts, including cashew and almond. The plant taxonomic classification of pistachio and other tree nuts does appear to predict allergenic cross-reactivity.

Porcel S, Sánchez AB, Rodríguez E, Fletes C, Alvarado M, Jiménez S, Hernández J. 2006. Food-dependent exercise-induced anaphylaxis to pistachio. J Investig Allergol Clin Immunol.;16(1):71-3. We report the case of a 16-year-old male who, 30 minutes after beginning to play football with previous ingestion of pistachio nuts, experienced an anaphylactic reaction. Prick-by-prick test with roasted pistachios was negative. Specific IgE antibodies to pistachio, cashew nuts and mango were negative. An open oral challenge test with pistachio in resting conditions was negative. Treadmill ergonometric stress in a fasting state and 60 minutes after a meal without pistachio gave negative results. A specific food exercise challenge 60 minutes after ingestion of 50 g pistachio nuts was positive, showing mild diffuse erythema and small wheals in face and thorax. To the best of our knowledge, this is the first described case of specific food dependent exercise-induced anaphylaxis to pistachio. Negative allergologic tests is an unusual condition, since most cases appear to be IgE-mediated. In this case, a positive specific food exercise challenge test provided a definite diagnosis.

Ros E. 2009. Nuts and novel biomarkers of cardiovascular disease. Am J Clin Nutr. 89 (suppl): 1649S-56S. Nuts are energy-dense foods, rich in total fat and unsaturated fatty acids. The favorable fatty acid profile probably contributes to the beneficial effects of nut consumption observed in epidemiologic studies (prevention of coronary heart disease and diabetes) and feeding trials (cholesterol lowering). Besides fat, the complex matrices of nuts contain many bioactive compounds: vegetable protein, fiber, minerals, tocopherols, and phenolic compounds. By virtue of their unique composition, nuts are likely to benefit newer cardiovascular risk biomarkers, such as LDL oxidizability, soluble inflammatory molecules, and endothelial dysfunction. Protection of LDL oxidation by nut intake has been documented in some, but not all, clinical studies. In one study, feeding one daily serving of mixed nuts was associated with lower oxidized LDL concentrations. Regarding inflammation, cross-sectional studies have shown that nut consumption is associated with lower concentrations of circulating inflammatory molecules and higher plasma adiponectin, a potent anti-inflammatory adipokine. Clinical studies with nuts have documented reduced inflammatory cytokine concentrations but no consistent changes of C-reactive protein. Only walnuts have been formally tested for effects on endothelial function. After both walnut diets and single walnut meals, favorable vasoreactivity changes have been observed. Walnut consumption also reduced expression of endothelin 1, a potent endothelial activator, in an animal model of accelerated atherosclerosis. Beneficial effects on vascular reactivity may be ascribed to several constituents of walnuts: L-arginine, the precursor of nitricoxide, a-linolenic acid, and phenolic antioxidants. Although more studies are warranted, the emerging picture is that nut consumption beneficially influences cardiovascular risk beyond cholesterol lowering.

Ros E, Tapsell LC, Sabaté J. 2010. Nuts and berries for heart health. Curr Atheroscler Rep. 12:397–406. Nuts are nutrient-dense foods with complex matrices rich in unsaturated fatty acids and other bioactive compounds, such as L-arginine, fiber, minerals, tocopherols, phytosterols, and polyphenols. By virtue of their unique composition, nuts are likely to beneficially impact heart health. Epidemiologic studies have associated nut consumption with a reduced incidence of coronary heart disease in both genders and diabetes in women. Limited evidence also suggests beneficial effects on hypertension and inflammation. Interventional studies consistently show that nut intake has a cholesterol-lowering effect and there is emerging evidence of beneficial effects on oxidative stress, inflammation, and vascular reactivity. Blood pressure, visceral adiposity, and glycemic control also appear to be positively influenced by frequent nut consumption without evidence of undue weight gain. Berries are another plant food rich in bioactive phytochemicals, particularly flavonoids, for which there is increasing evidence of benefits on cardiometabolic risk that are linked to their potent antioxidant power.

Ryan E, Galvin K, O'Connor TP, Maguire AR, O'Brien NM. 2006. Fatty acid profile, tocopherol, squalene and phytosterol content of brazil, pecan, pine, pistachio and cashew nuts. Int J Food Sci Nutr. May-Jun;57(3-4):219-28. Nuts contain bioactive constituents that elicit cardio-protective effects including phytosterols, tocopherols and squalene. The objective of the present study was to determine the total oil content, peroxide value, fatty acid composition and levels of tocopherols, squalene and phytosterols in oil extracted from freshly ground brazil, pecan, pine, pistachio and cashew nuts. The total oil content of the nuts ranged from 40.4 to 60.8% (w/w) while the peroxide values ranged from 0.14 to 0.22 mEq O2/kg oil. The most abundant monounsaturated fatty acid was oleic acid (C18:1), while linoleic acid (C18:2) was the most prevalent polyunsaturated fatty acid. The levels of total tocopherols ranged from 60.8 to 291.0 mg/g. Squalene ranged from 39.5 mg/g oil in the pine nut to 1377.8 mg/g oil in the brazil nut. beta-Sitosterol was the most prevalent phytosterol, ranging in concentration from 1325.4 to 4685.9 mg/g oil. In conclusion, the present data indicate that nuts are a good dietary source of unsaturated fatty acids, tocopherols, squalene and phytosterols.

Sabaté J, Wien M. 2010. Nuts, blood lipids and cardiovascular disease. Asia Pac J Clin Nutr. 19(1):131-6. The aim of this paper is to evaluate nut-related epidemiological and human feeding study findings and to discuss the important nutritional attributes of nuts and their link to cardiovascular health. Frequent nut consumption has been found to be protective against coronary heart disease in five large epidemiological studies across two continents. A qualitative summary of the data from four of these studies found an 8.3% reduction in risk of death from coronary heart disease for each weekly serving of nuts. Over 40 dietary intervention studies have been conducted evaluating the effect of nut containing diets on blood lipids. These studies have demonstrated that intake of different kinds of nuts lower total and LDL cholesterol and the LDL: HDL ratio in healthy subjects or patients with moderate hypercholesterolaemia, even in the context of healthy diets. Nuts have a unique fatty acid profile and feature a high unsaturated to saturated fatty acid ratio, an important contributing factor to the beneficial health effects of nut consumption. Additional cardioprotective nutrients found in nuts include vegetable protein, fiber, alpha-tocopherol, folic acid, magnesium, copper, phytosterols and other phytochemicals.

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.

Sari I, Baltaci Y, Bagci C, Davutoglu V, Erel O, Celik H, Ozer O, Aksoy N, Aksoy M. 2010. Effect of pistachio diet on lipid parameters, endothelial function, inflammation, and oxidative status: A prospective study. Nutrition. Apr;26(4):399-404. OBJECTIVE: Recent studies have suggested that nuts have favorable effects beyond lipid lowering. We aimed to investigate effect of the Antep pistachio (Pistacia vera L.) on blood glucose, lipid parameters, endothelial function, inflammation, and oxidation in healthy young men living in a controlled environment. METHODS: A Mediterranean diet was administered to normolipidemic 32 healthy young men (mean age 22 y, range 21-24) for 4 wk. After 4 wk, participants continued to receive the Mediterranean diet but pistachio was added for 4 wk by replacing the monounsaturated fat content constituting 20% of daily caloric intake. Fasting blood samples and brachial endothelial function measurements were performed at baseline and after each diet. RESULTS: Compared with the Mediterranean diet, the pistachio diet decreased glucose (P (P 0.001, -23.2 ± 11.9%), total cholesterol (P 0.001, -21.2 ±9.9%), and triacylglycerol (P = 0.008, -13.8 ±33.8%) significantly and high-density lipoprotein (P = 0.069, —3.1 ± 11.7%) non-significantly. Total cholesterol/high-density lipoprotein and low-density lipoprotein/high-density lipoprotein ratios decreased significantly (P 0.001 for both). The pistachio diet significantly improved endothelium-dependent vasodilation (P = 0.002, 30% relative increase), decreased serum interleukin-6, total oxidant status, lipid hydroperoxide, and malondialdehyde and increased superoxide dismutase (P 0.001 for all), whereas there was no significant change in C-reactive protein and tumor necrosis factor-a levels. CONCLUSION: In this trial, we demonstrated that a pistachio diet improved blood glucose level, endothelial function, and some indices of inflammation and oxidative status in healthy young men. These findings are in accordance with the idea that nuts, in particular pistachio nuts, have favorable effects beyond lipid lowering that deserve to be evaluated with prospective follow-up studies.

Sheridan MJ, Cooper JN, Erario M, Cheifetz CE, 2007. Pistachio nut consumption and serum lipid levels. Am Coll Nutr. 26(2):141-8. OBJECTIVE: Clinical and epidemiological studies have reported the beneficial effects of tree nuts and peanuts on serum lipid levels. We studied the effects of consuming 15% of the daily caloric intake in the form of pistachio nuts on the lipid profiles of free-living human subjects with primary, moderate hypercholesterolemia (serum cholesterol greater than 210 mg/dL). METHODS: design: Randomized crossover trial. setting: Outpatient dietary counseling and blood analysis. Subjects: 15 subjects with moderate hypercholesterolemia. intervention: Fours weeks of dietary modification with 15% caloric intake from pistachio nuts. Measures of outcome: Endpoints were serum lipid levels of total cholesterol, HDL-C, LDL-C, VLDL-C, triglycerides and apolipoproteins A-1 and B-100. BMI, blood pressure, and nutrient intake (total energy, fat, protein, and fiber) were also measured at baseline, during, and after dietary intervention. RESULTS: No statistically significant differences were observed for total energy or percent of energy from protein, carbohydrate or fat. On the pistachio nut diet, a statistically significant decrease was seen for percent energy from saturated fat (mean difference, -2.7%; 95% CI, -5.4% to -0.08%; p = 0.04). On the pistachio nut diet, statistically significant increases were seen for percent energy from polyunsaturated fat (mean difference, 6.5%; 95% CI, 4.2% to 8.9%; p<.0001 and="" fiber="" intake="" difference="" g="" ci="" to="" p="0.0003)." on="" the="" pistachio="" diet="" statistically="" significant="" reductions="" were="" seen="" in="" tc="" ldl-c="" b-100="" a="" increase="" was="" hdl-c="" no="" differences="" for="" total="" cholesterol="" triglycerides="" vldl-c="" apolipoprotein="" a-1="" or="" b-100.="" changes="" observed="" bmi="" blood="" pressure.="" conclusion:="" consisting="" of="" calories="" as="" nuts="" ounces="" per="" day="" over="" four-week="" period="" can="" favorably="" improve="" some="" lipid="" profiles="" subjects="" with="" moderate="" hypercholesterolemia="" may="" reduce="" risk="" coronary="" disease.="">

Sicherer SH, Muñoz-Furlong A, Godbold JH, Sampson HA. US prevalence of self-reported peanut, tree nut, and sesame allergy: 11-year follow-up. 2010. J Allergy Clin Immunol. Jun;125(6):1322-6. BACKGROUND: Allergy to peanuts and tree nuts (TNs) is the leading cause of fatal allergic reactions in the United States, and the prevalence appears to be increasing. OBJECTIVES: We sought to determine the US prevalence of self-reported peanut, TN, and sesame allergy in 2008 and compare results with comparable surveys conducted in 1997 and 2002. METHODS: A nationwide, cross-sectional, random telephone survey for peanut and TN allergy was conducted with a previously used questionnaire, with additional questions about sesame. RESULTS: A total of 5,300 households (13,534 subjects) were surveyed (participation rate, 42% vs 52% in 2002 and 67% in 1997). Peanut allergy, TN allergy, or both was reported by 1.4% of subjects (95% CI, 1.2% to 1.6%) compared with 1.2% in 2002 and 1.4% in 1997. For adults, the prevalence was 1.3% (95% CI, 1.1% to 1.6%), which was not significantly different from prior surveys. However, the prevalence of peanut or TN allergy for children younger than 18 years was 2.1% (95% CI, 1.6% to 2.7%) compared with 1.2% in 2002 (P = .007) and 0.6% in 1997 (P 3 million subjects) and appear to be increasingly reported among children over the past decade. Sesame allergy is reported much less commonly.

Tomaino A, Martorana M, Arcoraci T, Monteleone D, Giovinazzo C, Saija A. 2010. Antioxidant activity and phenolic profile of pistachio (Pistacia vera L., variety Bronte) seeds and skins. Biochimie. Sep;92(9):1115-22. Pistachio (Pistacia vera L.; Anacardiaceae) is native aride zones of Central and West Asia and distributed throughout the Mediterranean basin. In Italy, a pistachio cultivar of high quality is typical of Bronte (Sicily), an area around the Etna volcano, where the lava land and climate allow the production of a nut with intense green color and aromatic taste, very appreciated in international markets. Pistachio nuts are a rich source of phenolic compounds, and have recently been ranked among the first 50 food products highest in antioxidant potential. Pistachio nuts are often used after removing the skin, which thus represents a significant by-product of pistachio industrial processing. The present study was carried out to better characterize the phenolic composition and the antioxidant activity of Bronte pistachios, with the particular aim to evaluate the differences between pistachio seeds and skins. The total content of phenolic compounds in pistachios was shown to be significantly higher in skins than in seeds. By HPLC analysis, gallic acid, catechin, eriodictyol-7-O-glucoside, naringenin-7-O-neohesperidoside, quercetin-3-O-rutinoside and eriodictyol were found both in pistachio seeds more than in skins; furthermore, genistein-7-O-glucoside, genistein, daidzein and apigenin appeared to be present only in pistachio seeds, while epicatechin, quercetin, naringenin, luteolin, kaempferol, cyanidin-3-O-galactoside and cyanidin-3-Oglucoside are contained only in pistachio skins. The antioxidant activity of pistachio seeds and skins was determined by means of four different assays (DPPH assay, Folin-Ciocalteau colorimetric method and TEAC assay, SOD-mimetic assay). As expected on the basis of the chemical analyses, pistachio skins have been shown to possess a better activity with respect to seeds in all tests. The excellent antioxidant activity of pistachio skins can be explained by its higher content of antioxidant phenolic compounds. By HPLC-TLC analysis, gallic acid, catechin, cyanidin-3-O-galactoside, eriodictyol-7-O-glucoside and epicatechin appeared to be responsible for the antioxidant activity of pistachio skin, together with other unidentified compounds. In conclusion, our work has contributed to clarify some particular characteristics of Bronte pistachios and the specific antioxidant power of pistachio skins. Introduction of pistachios in daily diet may be of undoubted utility to protect human health and well-being against cancer, inflammatory diseases, cardiovascular pathologies and, more generally, pathological conditions related to free radical overproduction. On the other hand, pistachio skins could be successfully employed in the food, cosmetic and pharmaceutical industries.

West SG, Gebauer SK, Kay CD, Bagshaw DM, Savastano DM, Diefenbach C, Kris-Etherton PM. Diets containing pistachios reduce systolic blood pressure and peripheral vascular responses to stress in adults with dyslipidemia. Hypertension. 2012 Jul;60(1):58-63. Nut consumption reduces cardiovascular risk, and reductions in blood pressure and peripheral vascular resistance may be important mediators of this relationship. We evaluated effects of pistachios on flow-mediated dilation and blood pressure response to acute stress. Twenty-eight adults with dyslipidemia completed a randomized, crossover, controlled-feeding study. All of the meals were provided and calories were controlled. After 2 weeks on a typical Western diet (35% total fat and 11% saturated fat), test diets were presented in counterbalanced order for 4 weeks each: a low-fat control diet (25% total fat and 8% saturated fat), a diet containing 10% of energy from pistachios (on average, 1 serving per day; 30% total fat and 8% saturated fat), and a diet containing 20% of energy from pistachios (on average, 2 servings per day; 34% total fat and 8% saturated fat). None of the resting hemodynamic measures significantly differed from pretreatment values. When resting and stress levels were included in the repeated-measures analysis, average reductions in systolic blood pressure were greater after the diet containing 1 serving per day versus 2 servings per day of pistachios (mean change in systolic blood pressure, -4.8 vs -2.4 mm Hg, respectively; P

Wu X, Beecher GR, Holden JM, Haytowitz DB, Gebhardt SE, Prior RL. 2004. Lipophilic and hydrophilic antioxidant capacities of common foods in the United States. J Agric Food Chem. Jun 16;52(12):4026-37. Both lipophilic and hydrophilic antioxidant capacities were determined using the oxygen radical absorbance capacity (ORAC(FL)) assay with fluorescein as the fluorescent probe and 2,2'-azobis(2-amidinopropane) dihydrochloride as a peroxyl radical generator on over 100 different kinds of foods, including fruits, vegetables, nuts, dried fruits, spices, cereals, infant, and other foods. Most of the foods were collected from four different regions and during two different seasons in U.S. markets. Total phenolics of each sample were also measured using the Folin-Ciocalteu reagent. Hydrophilic ORAC(FL) values (H-ORAC(FL)) ranged from 0.87 to 2641 micromol of Trolox equivalents (TE)/g among all of the foods, whereas lipophilic ORAC(FL) values (L-ORAC(FL)) ranged from 0.07 to 1611 micromol of TE/g. Generally, L-ORAC(FL) values were

Zhang J, Kris-Etherton PM, Thompson JT, Vanden Heuvel JP. 2010. Effect of pistachio oil on gene expression of IFN-induced protein with tetratricopeptide repeats 2: A biomarker of inflammatory response. Molecular Nutrition & Food Research. May;54 Suppl 1:S83-92. When incorporated into the diet, pistachios have a beneficial effect on lipid and lipoprotein profiles. However, little is known about potential anti-inflammatory properties. This study was conducted to determine whether pistachio oil and an organic extract from pistachio oil extract (PE) regulated expression of inflammation-related genes. A mouse macrophage cell line (RAW 264.7 cells) was treated with pistachio oil and gene expression microarray analyses were performed. Pistachio oil significantly affected genes involved in immune response, defense response to bacteria, and gene silencing, of which INF-induced protein with tetratricopeptide repeats 2 (Ifit-2) was the most dramatically reduced. PE reduced the LPS-induced Ifit-2 by 78% and the bioactive molecules contained in PE, linoleic acid, and β-sitosterol recapitulated this inhibition. Promoter analysis identified two adjacent IFN-stimulated response elements, which lie between -110 and -85bp of the 5’-flanking region of the Ifit-2 promoter, as being responsive to LPS activation and inhibition by PE. Our results indicate that pistachio oil and bioactive molecules present therein decrease Ifit-2 expressions, and due to the sensitivity of this effect, this gene is a potential biomarker for monitoring diet-induced changes in inflammation.