Nutritional information

Pistachios are a nutritionally dense food. In a 100 gram serving, pistachios provide 562 calories and are a rich source (20% or more of the Daily Value or DV) of protein, dietary fiber, several dietary minerals and the B vitamins, thiamin and especially vitamin B₆ at 131% DV (table).^[31] Pistachios are a good source (10–19% DV) of calcium, riboflavin, vitamin B₅, folate, vitamin E , and vitamin K (table).

The fat profile of raw pistachios consists of saturated fats, monounsaturated fats and polyunsaturated fats.^[31][32] Saturated fatty acids include palmitic acid (10% of total) and stearic acid (2%).^[32] Oleic acid is the most common monounsaturated fatty acid (51% of total fat)^[32] and linoleic acid, a polyunsaturated fatty acid, is 31% of total fat.^[31] Relative to other tree nuts, pistachios have a lower amount of fat and calories but higher amounts of potassium, vitamin K, γ-tocopherol, and certain phytochemicals such as carotenoids and phytosterols.^[30][33]

Research and health effects

In July 2003, the United States' Food and Drug Administration (FDA) approved the first qualified health claim specific to seeds lowering the risk of heart disease: "Scientific evidence suggests but does not prove that eating 1.5 ounces (42.5 g) per day of most nuts, such as pistachios, as part of a diet low in saturated fat and cholesterol may reduce the risk of heart disease".^[34] Although pistachios contain many calories, epidemiologic studies have provided strong evidence that their consumption is not associated with weight gain or obesity.^[30]

A 2015 systematic review and meta-analysis of randomized controlled trials concluded that pistachio consumption in persons without diabetes mellitus appears to modestly lower systolic and diastolic blood pressure.^[35] Several mechanisms for pistachios' antihypertensive properties have been proposed. These mechanisms include pistachios' high levels of the amino acid arginine (a precursor of the blood vessel dilating compound nitric oxide); high levels of phytosterols and monounsaturated fatty acids; and improvement of endothelial cell function through multiple mechanisms including reductions in circulating levels of oxidized low density lipoprotein cholesterol and pro-inflammatory chemical signals.^[35]