What Happens to Your Gut Health When You Eat Pistachios Every Night?

A recent study found that people with prediabetes who ate a handful of pistachios each night had beneficial changes in their gut microbiome. These findings suggest regularly eating pistachios may help support gut health, among other things.

The Link Between Pistachios and Gut Health

Researchers found that eating about half a cup of pistachios each night for 12 weeks slightly changed the gut microbiome in adults with prediabetes.

There was an increase in beneficial bacteria like Roseburia and Lachnospiraceae, and a reduction in less helpful bacteria such as Flavonifractor.

This effect could be due to the nutrients found in pistachios—such as fiber, polyphenols, and prebiotics—which are thought to support beneficial gut bacteria and may help reduce inflammation in the gut.

While these changes suggest a positive shift in gut health, more studies are needed to confirm long-term effects and broader health impacts.

Health Benefits of Pistachios

Pistachios may offer more than just gut health support. In addition to influencing the microbiome, they’ve been linked to benefits in heart health, blood sugar control, and even weight management.

1. Boosts Heart Health

Pistachios are best known for their heart-healthy properties. Regular consumption has been shown to lower total cholesterol, “bad” LDL cholesterol, and triglycerides, while slightly increasing or maintaining levels of “good” HDL cholesterol.

Some research has found that pistachios lower blood pressure when eaten consistently, but more research needs to be done. High blood pressure is linked to conditions like heart attacks and stroke, so maintaining a healthy blood pressure is key to preventing other diseases.

On top of that, because pistachios are rich in nutrients like healthy fats, fiber, potassium, vitamin B6, and antioxidants, they may help reduce inflammation and protect cells from damage.

Some research also shows that pistachios may improve blood vessel function and reduce arterial stiffness, which contribute to a healthier heart.

2. Helps with Blood Sugar Control

Pistachios may also support better blood sugar control, especially for those with prediabetes, metabolic syndrome, or a high risk of cardiovascular disease.

Studies have found that eating up to 1/3 cup of pistachios each day can lower fasting blood sugar, insulin levels, and insulin resistance.

There’s also some evidence of improvements in long-term blood sugar control (measured by A1C), although those results are less consistent across studies.

3. May Support Weight Loss

While not as thoroughly researched as other benefits, some studies suggest that pistachios might support weight loss efforts. People who included pistachios in their diet daily tended to eat more fiber and less added sugar compared to those who didn’t.

This could make pistachios a useful snack for those aiming to lose or maintain weight, since diets high in fiber can help you feel full longer. This is especially true when paired with an overall healthy diet and regular physical activity.

Pistachio Nutrition Facts

Compared to other commonly consumed nuts, pistachios stand out for their nutrient density. They contain more fiber, essential amino acids, potassium, and vitamins A than some of their nut counterparts. On top of that, they’re a good source of protein. 

Here’s what you get in a one-ounce (about 1/8 cup) serving of unshelled pistachios:

• Calories: 159
• Protein: 6 grams
• Fiber: 3 grams
• Potassium: 289 mg
• Vitamin A: 146 IU