Pistachio Nutrition Facts and Health Benefits

The pistachio, a small yet mighty nut, has been cherished for thousands of years for its distinctive flavor, vibrant color, and numerous health benefits. From ancient Persia to modern-day gourmet cuisine, pistachios have played a significant role in human history, culture, and economy. This article delves into the fascinating journey of pistachios, tracing their origins, cultural significance, and the evolution of their cultivation.

Origins of Pistachios

Pistachios (scientific name Pistacia vera) are one of the oldest flowering nut trees, with evidence of their cultivation dating back to 7000 BC. The pistachio tree is believed to have originated in the regions of Central Asia and the Middle East, particularly in modern-day Iran and Afghanistan. The semi-arid climate of these regions, characterized by hot summers and cold winters, provides the ideal growing conditions for pistachios.

Ancient Cultivation and Trade

Pistachios were highly prized in ancient times, particularly in Persia (modern-day Iran), where they were considered a delicacy for the royal family and the aristocracy. The nut's distinctive green color, rich flavor, and ability to be stored for long periods made it a valuable commodity. As trade routes such as the Silk Road developed, pistachios were introduced to other parts of the world, including the Mediterranean, China, and India.

The Romans, who encountered pistachios through their conquests in the East, quickly developed a taste for the nut. According to historical records, Emperor Vitellius is credited with bringing pistachios to Rome in the first century AD, where they became a popular snack among the Roman elite. From Rome, the cultivation of pistachios spread throughout the Mediterranean, particularly in regions like Greece, Sicily, and Spain.

Pistachios in the Middle Ages

During the Middle Ages, pistachios continued to be a luxury item, often used in the elaborate feasts of the European nobility. The nuts were also introduced to North Africa and Southern Europe by the Moors, who further spread their cultivation. Despite their popularity in certain regions, pistachios remained relatively unknown in Northern Europe, where the climate was not conducive to their growth.

In the Islamic world, pistachios were highly esteemed not only for their flavor but also for their medicinal properties. Arab physicians, such as Avicenna, wrote about the health benefits of pistachios, which were believed to aid digestion, improve vitality, and promote overall well-being. The nut was also used in various traditional dishes and sweets, a practice that continues to this day.

Pistachios in the New World

Pistachios were introduced to the New World by Spanish explorers and settlers in the 16th century. However, it wasn't until the 19th century that commercial cultivation of pistachios began in the United States. The first pistachio trees in the U.S. were planted in California in the late 1800s, thanks to the efforts of agricultural pioneers who recognized the potential of the nut in the region's Mediterranean-like climate.

The commercial production of pistachios in the United States truly took off in the mid-20th century. In 1958, the U.S. Department of Agriculture (USDA) established a program to develop a domestic pistachio industry, which involved importing high-quality pistachio trees from Iran. The program was a success, and by the 1970s, California had become a major producer of pistachios, rivaling Iran in global production.

The Modern Pistachio Industry

Today, pistachios are a global commodity, with major producers including Iran, the United States (67%), Iran (17%) and Turkey (11%). Greece only produces 1% of the world's pistachios, making them the most coveted. The nut is enjoyed in a wide variety of forms, from raw and roasted to salted and flavored, and is used in an array of culinary applications, including desserts, snacks, and savory dishes.

The global demand for pistachios has grown significantly in recent years, driven by increased awareness of their health benefits. Pistachios are rich in protein, healthy fats, fiber, and antioxidants, making them a popular choice among health-conscious consumers. They are also an excellent source of vitamins and minerals, including vitamin B6, potassium, and magnesium.

Pistachios in Culture and Cuisine

Pistachios have not only been valued for their taste and nutritional benefits but also for their cultural and symbolic significance. In many cultures, pistachios are associated with good fortune, abundance, and celebration. For example, in Iran, pistachios are a common feature in Nowruz (Persian New Year) celebrations, symbolizing prosperity and renewal.

In culinary traditions around the world, pistachios play a central role. In the Middle East, they are a key ingredient in sweets such as baklava, Turkish delight, and halva. In Italy, pistachios are used in everything from gelato to pesto. In India, they are often incorporated into rich desserts like kulfi and barfi.

Health Benefits

Nutritional Information (28g portion of 49 pistachios, unroasted & unsalted) [1]

 

Low Calorie, High Protein

Everyone knows that eating nuts have many health benefits, but also provide lots of calories. Fortunately, pistachios are among the lowest-calorie nuts! One ounce (28g) contains only 159 calories when compared with walnuts (185 calories) and pecans (193 calories) [2,3,4].

Pea protein comprises about 20% of a pistachio's weight, making them only second to almonds when it comes to protein content [5]. Pistachios also have a higher ratio of essential amino acids - the building blocks of protein - than any other nut! [6] These amino acids are considered essential, and because your body cannot make them, you must eat them. Another semi-essential amino acid, L-arginine, accounts for 2% of these amino acids. This is converted into nitric oxide, a compound that causes your blood vessels to dilate, which aids blood flow [7].

Healthy Gut Bacteria

Pistachios are high in fibre, providing 3g per serving [2].

Most fibre moves through your digestive system mostly undigested, while other fibre is digested by the good bacteria in your gut, acting as prebiotics. Gut bacteria then ferments the fibre and converts it into short-chain fatty acids which provide several health benefits such as a reduced risk of developing digestive disorders, cancer and heart disease [8,9]. Butyrate is perhaps among the most beneficial short-chain fatty acid. Eating pistachios has been shown to increase the number of butyrate-producing bacteria in the gut to a greater extent than eating almonds [10].

Promotes Blood Vessel Health

The endothelium is the inner lining of blood vessels. It is important that this functions correctly as endothelial dysfunction is a risk factor for heart disease [11]. Vasodilation is the widening or dilating of blood vessels. Endothelial dysfunction is characterised by reduced vasodilation, which decreases blood flow. Nitric oxide is a compound which plays an important role in vasodilation. It causes blood vessels to dilate by signalling the smooth cells in the endothelium to relax [12].

Pistachios are a great source of the amino acid L-arginine, which is converted into nitric oxide in the body, meaning these tiny nuts play an important role in promoting blood vessel health.

One study in 42 patients who consumed 1.5 ounces (40g) a day of pistachios for 3 months showed improvements in markers of endothelial function and vascular stiffness [13]. Another 4-week study where 32 healthy young men consumed a diet where 20% of their calories came from pistachios found that endothelium-dependent vasodilation improved by 30%, compared to when they followed a Mediterranean diet [14].

Proper blood flow is important for many bodily functions, including erectile function. In one study, men with erectile dysfunction experienced a 50% improvement in parameters of erectile dysfunction after eating 3.5 ounces (100g) of pistachios every day for 3 weeks [15]. That being said, a 100g serving of pistachios is quite a lot of nuts to consume, containing around 557 calories.

Vitamin B6

Pistachios are high in protein, fibre and antioxidants. They also boast several other important nutrients, including vitamin B6 and potassium. Pistachios are one of the most B6-rich foods around. Vitamin B6 is important for several bodily functions, including blood sugar regulation and the formation of haemoglobin, a molecule that carries oxygen in red blood cells. 

High in Antioxidants 

Antioxidants prevent cell damage and play a key role in reducing the risk of diseases such as cancer. Pistachios are the third-most antioxidant-rich nut [16].

In a 4-week study, participants who ate either one or two servings of pistachios per day had greater levels of lutein and γ-Tocopherol, compared with participants who did not eat pistachios [17]. 

Among nuts, pistachios have the highest content of lutein and zeaxanthin, both of which are very important antioxidants for eye health [18,19]. They protect your eyes from damage caused by blue light and age-related macular degeneration, a condition in which your central vision is impaired or lost [20,21]. Interestingly, the antioxidants found in pistachios are very accessible in the stomach making them more likely to be absorbed during digestion [22]. 

 Weight Loss Aid

Despite being an energy-dense food, nuts are one of the most weight loss-friendly foods. While few studies have looked at the effects of pistachios on weight, those that exist are promising. Pistachios are rich in fibre and protein, both of which increase feelings of fullness and help you eat less [23,24]. 

One 12-week weight loss program showed that those who ate 1.9 ounces (53g) of pistachios per day as an afternoon snack had twice the reduction in body mass index (BMI), compared with those who ate 2 ounces (56g) of pretzels per day [25].

Moreover, another 24-week study conducted in individuals with excess weight showed that those who consumed 20% of their calories in pistachios lost 0.6 inches (1.5cm) more from their waistlines than those who did not eat pistachios [26]. One factor possibly contributing to pistachios' weight loss properties is that their fat content might not be fully absorbed [27]. 

In fact, studies have demonstrated the malabsorption of fats from nuts. This is because part of their fat content is stuck within their cell walls, preventing it from being digested in the gut [28,29].

What's more, shelled pistachios are great for mindful eating, as shelling the nuts takes time and slows the rate of eating. The leftover shells also give you a visual clue of how many nuts you have eaten [30]. One study showed that individuals who ate in-shell pistachios consumed 41% fewer calories than individuals who ate shelled pistachios [31]. 

Lowers Cholesterol and Blood Pressure 

Pistachios can reduce your risk of heart disease in various ways.
In addition to being high in antioxidants, pistachios may lower blood cholesterol and improve blood pressure, thus lowering your risk of heart disease [32,33].
In fact, several studies have demonstrated the cholesterol-lowering effects of pistachios [34,35,36].
Many studies on pistachios and blood lipids are conducted by replacing part of the calories in a diet with pistachios. Up to 67% of these studies have shown reductions in total and LDL (bad) cholesterol and increases in HDL (good) cholesterol [37].
Meanwhile, none of these studies observed that eating pistachios harmed the blood lipid profile [38].
One 4-week study in people with high LDL cholesterol had participants consume 10% of their daily calories from pistachios.
The study showed that the diet lowered LDL cholesterol by 9%. What’s more, a diet consisting of 20% of calories from pistachios lowered LDL cholesterol by 12% [39].
In another study, 32 young men followed a Mediterranean diet for 4 weeks. Then, pistachios were added to that diet in place of its monounsaturated fat content, totalling about 20% of their daily calorie intake.
After 4 weeks on the diet, they experienced a 23% reduction in LDL cholesterol, 21% reduction in total cholesterol, and 14% reduction in triglycerides [40].
Moreover, pistachios seem to lower blood pressure more than other nuts.
A review of 21 studies found that eating pistachios reduced the upper limit of blood pressure by 1.82 mm/Hg and the lower limit by 0.8 mm/Hg [41]. 

Despite having a higher carbohydrate content than most nuts, pistachios have a low glycemic index, meaning they don't cause large blood sugar spikes. Perhaps unsurprisingly, studies have shown that eating pistachios can help promote healthy blood sugar levels. One study showed that when 2 ounces (56g) of pistachios were added to a carb-rich diet, healthy individuals' blood sugar response after a meal was reduced by 20-30% [42,43]. This means that simply adding pistachios into your diet can help you manage your blood sugar levels in the long term! 

High in protein for vegans and vegetarians 

Pistachios contribute to a person's daily protein needs, at almost 6g of protein per 1oz serving (28g). Protein accounts for approximately 21% of the total weight of the nut, making it a good source for vegetarians and vegans, among others. Pistachios also boast a higher ratio of essential amino acids, the building blocks of protein, than any other nut, including almonds, hazelnuts, pecans and walnuts. Because pistachios have low caloric values and high fibre and protein content, they may benefit people who wish to manage their weight. A 2020 study found a daily serving of 1.5oz of pistachios helped reduce body mass index (BMI) and waist circumference in males and females with obesity, compared to a control group who did not eat an extra serving of pistachios every day. Learn more about the pros and cons of BMI measurements here.

Good for eye health

Pistachios are a rich source of the antioxidants lutein and zeaxanthin, which are essential for eye health.  According to the American Optometric Association, lutein and zeaxanthin reduce the chances of developing chronic eye conditions, such as cataracts. They can also help protect against age-related macular degeneration (AMD). AMD and cataracts are among the leading causes of blindness in the United States. Eating a healthy diet, including pistachios, is a promising way to help prevent these eye diseases from developing. Learn about vitamins that are good for eye health here. 

 

Reduces colon cancer risk 

Pistachios have been shown to reduce the risk of some cancers, such as colon cancer, due to their high fibre content. Scientists demonstrated this in 2017 with research that showed that roasting the nuts did not affect their health benefits, regarding colon cancer cells. 

 

Are pistachios fattening? 

Although pistachios are high in fat and calories, the fat they contain is monounsaturated fat. This type of fat can help lower low-density lipoproteins (LDL), or bad cholesterol and reduce the risk of stroke. 

The American Heart Association says that the majority of the fats in a person's diet should be monounsaturated fat to reduce the risk of cardiovascular problems. Eating pistachios in moderation should not affect a person's weight. One way to moderate pistachio intake is to buy the shelled versions. This can help slow down consumption, allowing the person to realise when they are full and reduce the risk of eating too much. 

 

Do pistachios cause constipation? 

Pistachios are a high fibre source, which means that they help to ease constipation, rather than cause it. However, people with nut intolerances or allergies may experience digestive problems such as diarrhoea, gas, bloating or stomach cramps [44]. People who suspect that they have a nut intolerance should speak to a healthcare professional before introducing nuts to their diet. 

 

Other effects

Pistachios release energy slowly, making them the ideal snack to have before working out. The protein they contain can also help the muscles to recover after exercise. Pistachios are also high in vitamin E and other antioxidants, which can help to provide some protection against certain forms of cancer. They also contain resveratrol, which has shown promise in treating people with Alzheimers and Parkinson's disease. However, the development of such treatment is in its early stages, and there is no evidence to suggest that eating pistachios can help reduce the risk of these conditions or treat the symptoms. 

 

Delicious and fun to eat 

Pistachios can be enjoyed in a variety of ways! Eat them as their own or sprinkle them onto salads, pizzas or stir them into your cake or brownie batter as a way to add some green to your daily desserts and dishes! My favourite ways include pistachio gelato or cheesecake. Like other nuts, they can be used to make pistachio pesto which makes a delicious pasta sauce or nut butter, which is delicious on toast and croissants. You can even try sprinkling them over your favourite oven-baked fish, adding them to your morning granola or making your own dessert crust. Lastly, pistachios can be enjoyed on their own as a convenient, tasty and healthy snack.