More Scientific Data Point to Health Benefits of Eating Pistachios Including Weight Control and Delivering Important Antioxidants
The information stockpile on the health benefits of eating pistachios on a daily basis continues to grow with two recent articles published in the journal Nutrition. A November/December 2012 review of published tree nut research points to the prevention of obesity and other health benefits with consumption of tree nuts, including pistachios. Additionally, a January 2013 paper confirms the release of key antioxidants and polyphenols from pistachios during digestion.
Add Nutrients, Not Weight, with Pistachios
The November/December review was conducted at the Institute for Biological Chemistry and Nutrition at the University of Hohenheim in Stuttgart, Germany and in the Department of Food Science, Nutrition and Technology at the University of Nairobi, Nairobi, Kenya. The review, led by Vellingiri Vadivel, Ph.D., aimed to clarify the relationship between tree nut consumption, including pistachios, and body weight in relation to other research findings of healthy outcomes primarily related to heart health.
According to Constance J. Geiger, Ph.D., R.D., who serves as a nutrition research consultant with the American Pistachio Growers, "This review reaffirms that while nuts are nutrient and energy dense, the research does not support that increased consumption may lead to unwanted body weight gain. In fact, the opposite was found: that eating nuts in moderate amounts does not increase body weight."
In addition to pistachios, the study examined mixed nuts, almonds, walnuts and peanuts. The authors looked at both epidemiologic research studies and short-term feeding trials.
They found that although tree nuts have high-fat content, most are unsaturated fats that may not be fully absorbed. Also, because of their energy density, protein and high-fiber content tree nuts are satisfying, which the authors suggested may reduce overeating. The review indicated that frequent nut consumption may lower the risk of obesity in healthy subjects. The authors concluded that the inclusion of these nuts, such as pistachios, in amounts of 30-50g/d is advisable to ensure various health benefits, including reducing the risk of heart disease and antioxidant effects. These benefits can be achieved without the risk of weight gain.
Antioxidants in Pistachios Released During Digestion
In the second study published in Nutrition in January 2013, pistachios were found to contain important antioxidants. These antioxidants, similar to those found in fruits and vegetables, were found to be released during digestion and thus were available to the body to provide health benefits. Results of this study were presented earlier in 2012 at the American Society of Nutrition conference in San Diego.
This investigation was conducted by the Model Gut Group at the Institute of Food Research (IFR) in the United Kingdom in association with the University of Messina, Italy. Polyphenols (catechins), carotenoids (beta-carotene, lutein, and zeaxanthin) and gamma- tocopherol (vitamin E), all with strong antioxidant qualities, were quantified in pistachios. The work was funded by American Pistachio Growers, a not for profit trade association that funds research on emerging science associated with the nut.
Giuseppina Mandalari, Ph.D., research scientist at IFR, was the lead investigator. According to Mandalari, "These results are the first to show the bioactive compounds are released during digestion and are available to be taken up by the body." She continues, "These nutrients contribute to the beneficial relationship between pistachio consumption and healthy outcomes, such as heart disease."
The bioaccessibility, the availability of nutrients to be absorbed by the body, of phytonutrients in whole foods such as pistachios is meaningful, especially when compared to nutrients ingested in supplements, whose bioavailability may not be known.
Pistachio Colors Tell a Story
Be sure to color your plate with pistachios. The antioxidants and polyphenols in pistachios can be identified by the green, yellow and purplish red colors in the kernel and skins. Those antioxidant compounds that are released include beta-carotene, lutein and zeaxanthin, which provide the yellow and possibly green colors. Green also comes from chlorophyll. Anthocyanins, also found in blueberries, give pistachios their purplish red color. The polyphenols, catechins, are slightly yellow or white. Not only do fruits and vegetables contain important antioxidants and polyphenols, but pistachios also provide these nutrients as identified by the array of colors in the kernels and skin.
The results of the bioaccessibility study along with the findings of a 2010 published study and trials by researchers at Pennsylvania State University are significant. The Penn State study addressed the positive effect of antioxidants-- tocopherols and lutein-- from pistachios on LDL cholesterol, and all of these findings combined point to a reduced risk of heart disease when pistachios are eaten daily.
Pistachios are a delicious, nutrient- packed snack food that has more than 15 important nutrients, including antioxidants, fiber and vegetable protein.
Antioxidants help protect the body from damage. Oxidation, a process that occurs through natural body functions such as exercise, produces free radicals. These free radicals can attack healthy cells and weaken them, making them more susceptible to damage. Antioxidants, such as vitamin E and carotenoids, which include beta-carotene and lutein, help protect cells from damage caused by free radicals. Pistachios have gamma tocopherol (a form of vitamin E), lutein/zeaxanthin and beta carotene (carotenoids). Research from Penn State University shows that these antioxidants are increased in the blood when pistachios are eaten. They are related to lowering oxidized bad cholesterol.
Pistachios are a cholesterol-free snack that contains just 1.5 grams of saturated fat and 13 grams of fat per serving, the majority of which comes from monounsaturated and polyunsaturated fat. A one-ounce serving of pistachios equals 49 nuts, which is more nuts per serving than any other snack nut. One serving has as much potassium (300 mg, 8 percent) as an orange (250 mg, 7 percent), making it a nutritious snack choice or ingredient to incorporate into daily diets.
About American Pistachio Growers
American Pistachio Growers is a voluntary trade association representing members who are pistachio growers, processors and industry partners in California, Arizona and New Mexico. These states represent 100% of the domestic commercial pistachio production. APG pistachios are the "Official Snack" of both USA Water Polo teams and the Miss California pageant. All share the goal of increasing national awareness about the nutritional benefits of pistachios. For more information, visit www.AmericanPistachios.org.
For more information, go to:
Vadivel V, Kunyanga CN, Biesalski HK. Health benefits of nut consumption with special reference to body weight control. Nutrition. 2012. Nov-Dec;28(11-12):1089-97. doi: 10.1016/j.nut.2012.01.004.
Mandalari G, Bisignano C, Filocamo A, Chessa S, SarÃ² M, Torre G, Faulks RM, Dugo P. Bioaccessibility of pistachio polyphenols, xanthophylls, and tocopherols during simulated human digestion. Nutrition. 2013 Jan;29(1):338-44. doi: 10.1016/j.nut.2012.08.004. PubMed PMID: 23237656.
Kay CD, Gebauer SK, West SG, Kris-Etherton PM. Pistachios increase serum antioxidants and lower serum oxidized-LDL in hypercholesterolemic adults. Journal of Nutrition. 2010 Jun;140(6):1093-8. doi: 10.3945/jn.109.117366. Epub 2010 Mar 31. PubMed PMID: 20357077; PubMed Central PMCID: PMC3140215.