Written by Jessica Patella, ND. This review analyzed data from 8 different studies which highlight the beneficial effects of pistachios on cholesterol levels. The researchers suggest that pistachios should be considered part of a healthy diet.
For the past 20 years, research has shown that nut consumption is associated with a reduced risk in cardiovascular disease (1,2). Cardiovascular disease affects 26.5 million adults in the United States (3). Up to this point, very little research has been done specifically looking at pistachio nuts in relation to cardiovascular disease. A recent review of 8 studies found that adding pistachios to a typical diet has a beneficial effect on cholesterol levels (1).
Pistachios have one of the most beneficial nutrient content of any nuts (1). They are rich in protein, good fats monounsaturated fatty acids, polyunsaturated fatty acids) and are the only tree nut to contain resveratrol, a compound associated with reduced risk of cardiovascular disease (1). Pistachios also are low in saturated fats, have no trans fats and no cholesterol (1).
A total of 8 small studies were included in the research review. The first study evaluated substituting pistachios for 20% of daily caloric intake from high-fat snacks or in place of high-fat snacks like potato chips. A total of 10 participants with high cholesterol levels were included (28-64 years). After 3 weeks of consuming pistachios, total cholesterol was reduced on average from 243 to 239 mg/dL (p<0.04) (1).
Another study included 28 participants, with an average age of 51 years. Participants consumed a control diet (low-fat with no pistachios), or 1 serving of pistachios per day or 2 servings of pistachios per day. The average total cholesterol decreased from 5.40 to 5.01 mmol/L (p<0.05) for those eating 1 serving of pistachios. It decreased to 4.92 mmol/L (p<0.05) for those eating 2 servings of pistachios per day. LDL “bad” cholesterol also decreased from 3.43 to 3.08 mmol/L and 2.98 mmol/L (p<0.05) with 1 and 2 servings of pistachios, respectively (1).
A study measuring cholesterol levels among participants with erectile dysfunction showed that eating 100 grams of pistachios per day improved cholesterol values over 3-weeks. The study included 17 men (average age 47.9 years) and showed an average decrease in total cholesterol from 179.5 to 148.3 mg/dL (P<0.008) and in LDL from 106.1 to 84.8 mg/dL (P<0.007). HDL “good” cholesterol increased from an average of 42 to 62.1 mg/dL (P<0.001) (1).
When 15% of daily caloric intake was substituted with pistachios instead of high-fat snacks, positive results were also observed. The study included 15 participants (average age 60 years) for 4 weeks. The only statistically significant change was the increase in HDL “good” cholesterol from 55 to 57 mg/dL (P<0.02) (1).
In younger adults from 21-24 years of age, consuming pistachios showed benefit. The study included 32 students that consumed a Mediterranean-type diet for 4 weeks, then a similar diet where 20% of calories were replaced by pistachios for 4 weeks. After consuming pistachios, the average total cholesterol reduced from 190.7 to 149.4 mg/dL (P<0.001), LDL “bad” cholesterol reduced from 124.5 to 95 mg/dL (P<0.001) and [glossy term=”triglycerides”] reduced from 112.1 to 91.1 mg/dL (P<0.0008) (1).
In healthy participants, positive results from eating pistachios were also observed. In this study, 44 healthy adults, all with normal cholesterol levels were randomly assigned to a regular diet group and the other to regular diet with 20% of calories from pistachios (65-75 grams per day) for 3 weeks. In the pistachio group, the average total cholesterol levels decreased from 4.08 to 3.61 mmol/L (P<0.05), average LDL “bad” cholesterol decreased from 1.94 to 1.89 mmol/L (P<0.05) and triglycerides decreased from 1.34 to 1.18 mmol/L (P<0.05) (1).
The final study in the review included 59 participants from 20-65 years of age. The participants were divided into two groups. One group consumed a 500 calorie deficient diet with a snack of 56 grams of salted pretzels for 12 weeks and the second group consumed a 500-calorie deficient diet with a snack of 53 grams of salted pistachios. In the pistachio group, the average triglyceride level decreased from 113 mg/dL at baseline to 88.1 mg/dL at 12-weeks (P<0.05) (1). The results from the control group were not given.
In conclusion, these findings from 8 different studies highlight the beneficial effects of pistachios on cholesterol levels, in all ages and stages of health. Therefore, the researchers recommended pistachios should be considered heart-healthy and part of a diet for individuals with heart disease or at risk for heart disease (1). Although results are from small groups and some of the benefits found were minor, the pattern for heart benefits was consistent. Confirmation from a larger controlled study would add weight to these findings.
Source: London, Hilary A., et al. “The impact of pistachio consumption on blood lipid profile: a literature review.” American Journal of Lifestyle Medicine 7.4 (2013): 274-277
Copyright © 2017 by SAGE Publications
Posted June 21, 2013.
Jessica Patella, ND, is a naturopathic physician specializing in nutrition and homeopathic medicine and offers a holistic approach to health. She earned her ND from Southwest College of Naturopathic Medicine in Tempe, AZ, and is a member of the North Carolina Association of Naturopathic Physicians. Visit her website at www.awarenesswellness.com.
References:
- London H, et al. The Impact of Pistachio Consumption on Blood Lipid Profile: A Literature Review. 2013 Am Journal of Lifestyle Med doi: 10.1177/1559827613479910
- Ros E. Health benefits of nut consumption. 2010 Nutrients 2:652-682.
- Heart Disease. Centers for Disease Control and Prevention.
