What Are the Health Benefits of Pistachios?

Written by Madeline Laguaite, Donna Siegfried
Medically Reviewed by Shruthi N, MD on August 31, 2025
6 min read

Pistachios are the seeds of the pistachio tree. They're usually green and have a slightly sweet taste. Pistachios are often called nuts, but they’re actually seeds. People have been eating them for thousands of years.

The kernels can be different colors, ranging from yellow to shades of green. They're usually about an inch long and half an inch in diameter. If you want to taste one, you'll have to crack open its hard shell first.

All of America’s commercial pistachios are grown in California, Arizona, and New Mexico. You can buy pistachios shelled, unshelled, roasted, salted, or unsalted. They’re in most grocery stores, and you can buy them in bulk from pistachio growers.

Pistachios are a nutritiousaddition to your diet. They are made up of 20% protein, a much higher calorie-to-protein ratio than that of most nuts. This protein can make you feel full longer and help you manage your weight.

Pistachios also boast a high amount of antioxidants, second only to walnuts and pecans. Antioxidants help fight against free radicals, which are compounds in your body that can harm cells, proteins, and DNA, causing premature aging as well as illnesses such as cancer, diabetes, and heart disease.

Pistachios are a good source of unsaturated fatty acids and potassium.

Like other nuts, pistachios are a staple of the Mediterranean diet, which has been linked to overall long-term health.

Pistachios are a complete protein. That means they provide all nine essential amino acids that your body needs. Research has found several possible health benefits of these tasty nuts, including:

Promotion of healthy gut bacteria

Pistachios are high in fiber, which can act as a prebiotic — a food that is digested by your gut's good bacteria to help them grow. Your gut bacteria are then able to ferment the fiber and convert it into short-chain fatty acids, which help reduce your risk of cancer, heart disease, and digestive disorders.

Lower blood pressure and cholesterol levels

Pistachios have been shown to have cholesterol-lowering effects. These nuts have fiber and high quantities of polyunsaturated and monounsaturated fats, all of which are linked to healthy cholesterol levels and reduced risk of heart disease. And research shows that eating pistachios — especially compared to other nuts — results in lower blood pressure.

Healthy blood sugar levels

Pistachios have a low glycemic index, which means that eating them doesn't cause large spikes in blood sugar. They also have antioxidants, carotenoids, and phenolic compounds, which all support healthy blood sugar levels.

Improved blood vessel health

Amino acids are considered essential, so if your body can't make them, you have to get them through your diet. Some studies suggest that the amino acids in pistachios lower the amount of fat and sugar (glycemic index) in your blood and can tone up your blood vessels, making them more flexible.

Better eye health

Pistachios have the highest levels of zeaxanthin and lutein among nuts, both of which protect your eyes from damage caused by blue light as well as macular degeneration, an eye disease that can cause vision loss as you age.

Weight loss

Eating pistachios may also help you lose weight. They're rich in fiber and protein, which can help you feel full and eat less.

A quick tip: Ditch the shelled pistachios and choose in-shell pistachios to snack on. In-shell pistachios promote eating slowly and mindfully, as it takes time to remove the shells. The shells also build up in front of you, showing how much you've eaten so far. Research has shown that people who ate in-shell pistachios consumed 41% fewer calories in a sitting than those who ate shelled pistachios.

Pistachios may have negative side effects for some people, including:

Higher intake of sodium

Raw pistachios don't have much sodium — one cup has about 1 milligram. But that's not always true for roasted pistachios, which are often salted. A cup of dry-roasted pistachios with salt has 526 milligrams of sodium. Too much sodium can put you at a higher risk for things such as high blood pressure, heart disease, and stroke. 

FODMAP risks

FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. Put more simply, FODMAPs are certain kinds of carbohydrates. People with irritable bowel syndrome (IBS) may limit FODMAPs in their diet to have better control over their symptoms. Pistachios are considered a high-FODMAP food because they contain fructans. If you have fructan intolerance — a bad reaction to this type of carbohydrate —pistachios might bother your belly. If so, you may have:

  • Bloating
  • Nausea
  • Pain in your belly

Allergy risks

Pistachios are tree nuts. Some people with tree nut allergies may have serious reactions to pistachios and should avoid them. Symptoms of an allergic reaction to pistachios can include:

  • Itchy mouth, eyes, skin, or throat
  • Trouble swallowing
  • Nausea and belly pain
  • Diarrhea
  • Congestion or a runny nose
  • Troubled breathing or shortness of breath
  • Anaphylaxis, a serious reaction that may make it hard to breathe

Anaphylactic shock can be fatal. If you have a tree nut allergy, always keep an auto-injector with epinephrine (or adrenaline) on hand. Epinephrine is the only treatment for anaphylactic shock.

If you're allergic to tree nuts like pistachios, be sure to read the labels on prepackaged foods to confirm they don't have trace amounts of tree nuts. Your doctor may also advise you to avoid peanuts. Peanuts and pistachios may cross-contaminate each other in the facilities where they're processed.

A 1-ounce serving of pistachios, which is about 49 kernels, has about 159 calories and:

  • 5.72 grams of protein
  • 7.7 grams of carbs
  • 12.85 grams of fat
  • 3 grams of fiber

Pistachios are cholesterol-free and a great source of vitamins and minerals, including:

  • Manganese
  • Phosphorous
  • Copper
  • Vitamin B6
  • Thiamine

They also pack quite a punch of potassium. In fact, a 2-ounce serving has more potassium than a large banana and as much fiber as a cup of cooked broccoli.

Pistachios can be tricky to eat since they have a tough shell. If there's a crack in the shell, you can use the shell of another pistachio to pry it open. If there is no crack, you can place the nuts on a cutting board, cover them with a towel, and hit them just hard enough so the shells open.

Pistachios will stay fresh (shelled or in shell) for up to a year in a refrigerator or for up to three years in the freezer.

You can enjoy them in dishes such as:

  • Salads
  • Ice cream or gelato
  • Baklava (a sweet pastry)
  • Pesto
  • Nut butter
  • Biscotti
  • Granola
  • Turkish delight
  • Yogurt
  • Sohan (a Persian pistachio brittle)

Pistachio nuts are nutritional powerhouses packed in shells. They are complete proteins and good sources of antioxidants, potassium, and unsaturated fats. They have nutrients that are known to help improve cholesterol levels and blood pressure. And they don't spike blood sugar. Pistachios can be eaten raw or roasted. And they can be added to many different foods. They are tree nuts, so avoid pistachios if you have a tree nut allergy. And if you follow a low-FODMAP diet, be aware that pistachios might bother your belly.

Are pistachio nuts fattening?

Any food that you overeat may be "fattening." Extra energy from calories your body doesn't need is stored in fat. Pistachios do contain fat (46 grams in 2/3 cup), but it is unsaturated fat, which is better for your heart. The fat in pistachios can make you feel full and satisfied. That can keep you from overeating. A review of 33 studies showed that eating nuts did not increase body weight or body mass index.

Are pistachios good for people who have diabetes?

Yes, if you have diabetes (and no tree nut allergy), pistachios are a good choice for a snack. They are low on the glycemic index, which means they won't spike blood sugar. One serving of pistachios (49 pistachios) has 8 grams of carbohydrate and 2 grams of sugar.

Are pistachios good for women?

Yes, pistachios are good for women and men. The health benefits of pistachios for the gut, blood vessels, and eyes apply to both sexes. Pistachios are a tree nut, and a study showed a lower risk of estrogen-negative breast cancer associated with eating tree nuts. The women in the study had gone through menopause and ate 10 grams of tree nuts daily.