Calories in Pistachios: Full Nutrition Breakdown

Pistachios are a vibrant green tree nut with a distinctive slightly sweet and earthy flavor, cultivated primarily in Iran, the United States, and Turkey. One ounce of dry-roasted pistachios (about 49 kernels) provides approximately 162 calories, 5.8 grams of protein, and 13 grams of fat, making them one of the lowest-calorie and highest-protein nuts per serving. They are an excellent source of vitamin B6, thiamine, copper, manganese, and phosphorus, and are notably rich in the antioxidant carotenoids lutein and zeaxanthin.

Calories by serving size:

Pistachios are unique among nuts for their high lutein and zeaxanthin content — carotenoid antioxidants most commonly associated with leafy greens — which support eye health and may help protect against age-related macular degeneration. They also have one of the highest potassium levels among nuts, with one ounce providing about 291 milligrams. The combination of relatively high protein, generous fiber, and lower fat content compared to many other nuts gives pistachios one of the most favorable calorie-to-nutrient ratios in the nut family.

Frequently Asked Questions (FAQ)

How many pistachios are in one ounce?

One ounce of shelled pistachio kernels contains approximately 49 individual nuts, which is significantly more individual pieces than most other nut servings. This higher count per serving can make pistachios feel more satisfying psychologically, as it takes longer to eat 49 small nuts than, say, 14 walnut halves. Research from Eastern Illinois University found that eating in-shell pistachios led people to consume about 41% fewer calories compared to eating pre-shelled pistachios, as the act of cracking open shells slows consumption and the pile of discarded shells provides a visual cue of how much has been eaten.

Are pistachios good for blood sugar control?

Pistachios have a relatively low glycemic index and have shown promising effects on blood sugar regulation in clinical studies. Research published in the Review of Diabetic Studies found that adding pistachios to a high-carbohydrate meal significantly reduced the post-meal blood sugar spike compared to eating the same meal without pistachios. The combination of healthy fats, protein, and fiber in pistachios slows the digestion and absorption of carbohydrates from other foods eaten at the same time. Several studies in people with type 2 diabetes have also found that regular pistachio consumption improved fasting blood glucose and insulin levels over time.

What gives pistachios their green color?

The distinctive green color of pistachios comes from chlorophyll, the same pigment responsible for the green color of leaves and plants. Pistachios are one of the few nuts that retain significant chlorophyll because the kernel develops while still enclosed in its shell, protecting the pigment from light degradation. The purple-reddish skin surrounding the green kernel contains anthocyanin antioxidants, making pistachios one of the most antioxidant-rich nuts when the skin is consumed. Greener pistachios are generally considered higher quality and tend to have a more delicate, slightly sweet flavor.

How do pistachios compare to almonds?

Pistachios and almonds are both nutrient powerhouses, but they have distinct nutritional strengths. Pistachios are slightly lower in calories per ounce (162 vs 164 kcal) and provide more vitamin B6, potassium, and carotenoid antioxidants (lutein and zeaxanthin). Almonds, on the other hand, offer more vitamin E, calcium, and fiber per serving. Both nuts are excellent sources of monounsaturated fat and have strong evidence supporting cardiovascular health benefits, so including both in the diet provides complementary nutrients.

Are salted pistachios unhealthy?

Salted pistachios contain added sodium, with a typical one-ounce serving of salted pistachios providing about 121 milligrams of sodium (roughly 5% of the recommended daily limit). While this amount is moderate, it can add up quickly if portions are not controlled, especially for people on a sodium-restricted diet due to high blood pressure or heart disease. Unsalted or lightly salted varieties are the better choice for those monitoring sodium intake. However, even salted pistachios retain all of their beneficial nutrients — protein, healthy fats, fiber, and micronutrients — so they are still a much more nutritious snack than most salty processed alternatives like chips or pretzels.