Pistachios for Inflammation

Overseen By Alexandra Hanlon, PhD

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: Virginia Polytechnic Institute and State University

Disqualifiers: Smoking, Pregnancy, Nut allergy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 3

Duration: 6 months

144 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It seems focused on diet and exercise habits, so you may not need to change your medications, but it's best to confirm with the study coordinators.

What data supports the effectiveness of pistachio consumption as a treatment for inflammation?

Research shows that pistachios have anti-inflammatory properties, as they can reduce inflammation markers in cells and animal models. The polyphenols in pistachios help protect against inflammation and oxidative stress, which are linked to various health benefits. ^{1 2 3 4 5}

Is pistachio consumption safe for humans?

Research suggests that pistachios, including their oil and extracts, have anti-inflammatory and antioxidant properties, which are generally considered safe for human consumption. Studies in animals and cell models show positive effects on inflammation and gut health, indicating potential safety and health benefits. ^{1 2 3 6 7}

How does pistachio consumption as a treatment for inflammation differ from other treatments?

Pistachio consumption is unique because it uses natural polyphenols found in pistachios to reduce inflammation and improve gut health, unlike many standard treatments that may rely on synthetic drugs. This approach not only targets inflammation but also positively affects gut microbiota, which is not a common focus of traditional anti-inflammatory treatments. ^{1 2 3 4 6}

What is the purpose of this trial?

Pistachio nuts (Pistacia vera L.) are a nutrient- and energy-dense food, and are a significant source of 15 different micronutrients. In addition to an excellent micronutrient profile, pistachios are a good source of monounsaturated and polyunsaturated fats (linoleic acid, oleic acid, and plant sterols). Pistachios have the lowest amount of total fat, and the highest protein, fiber, and phytosterol content compared to other nuts. They possess a high antioxidant content. Specifically, pistachios have high amounts of lutein, zeaxanthin, and phenolic compounds (e.g., anthocyanins, flavonoids, and proanthocyanidins). These aforementioned compounds are known for their anti-inflammatory effects. Pistachios also have been shown to reduce the risk of cardiovascular disease, metabolic syndrome, and all-cause mortality. The purpose of this study will be to determine the effects of consuming 1.5 ounces of pistachios per day compared to consuming no pistachios per day on inflammatory markers (creatine kinase, C-reactive protein, cortisol, Interleukin-8, tumor necrosis factor-alpha, copper-zinc superoxide dismutase, and glutathione peroxidase concentrations) and lean body mass in women and men, 40 to 60 years of age, who have been recreationally active for at least six months (exercising three to five days per week). It is hypothesized that pistachio consumption will significantly lower inflammatory response and significantly increase lean body mass. This will be a randomized study where participants will first complete a two-week baseline run-in period during which they will consume their typical diet. Following this, participants will be randomized to one of two groups for six months: consuming 1.5 ounces of pistachios per day or a control group (consuming no pistachios). Those consuming pistachios will be in addition to their usual diet. The overall goal of this study is to evaluate the effects of pistachio consumption on inflammatory markers and lean body mass in women and men, 40 to 60 years of age, who exercise three to five days per week. This study could provide a simple, healthy way for recreationally active individuals to decrease inflammation and improve body composition.

Research Team

Stella L Volpe, PhD

Principal Investigator

Virginia Polytechnic Institute and State University

Eligibility Criteria

This trial is for men and women aged 40-60 who are moderately active, exercising 3-5 days a week. It aims to see if eating pistachios affects inflammation and muscle mass.

Inclusion Criteria

Non-smokers

Not on an active weight loss program at the start of the study or any time during the study

I am between 40 and 60 years old.

Exclusion Criteria

Already consuming one or more ounces of pistachios several times a week

Unwilling to sign the informed consent document

Pregnant or lactating women

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Baseline Run-in

Participants consume their typical diet to assess participation prior to randomization

2 weeks

1 visit (in-person)

Treatment

Participants are randomized to consume 1.5 ounces of pistachios per day or no pistachios for six months

6 months

2 visits (in-person) at 3 and 6 months

Follow-up

Participants are monitored for changes in inflammatory markers and lean body mass

4 weeks

Treatment Details

Interventions

• Pistachio Consumption

Trial Overview Participants will either eat 1.5 ounces of pistachios daily or none at all for six months to study the effects on inflammatory markers and lean body mass.

Participant Groups

Group I: Arm 1: Pistachio group Experimental Treatment 1 Intervention

Participants will receive 1.5 ounces of pistachios to consume every day for 6 months. We will provide them a 3-month supply of pistachios, and they will receive another 3-month supply when they come in for their 3-month study visit (blood draw).

Group II: Arm 2: No pistachio group Active Control 1 Intervention

This group will not get any pistachios.

Who Is Running the Clinical Trial?

Virginia Polytechnic Institute and State University

Lead Sponsor

Trials

162

Recruited

26,900+

Findings from Research

Polyphenol extracts from both natural raw (NP) and roasted salted (RP) pistachios show significant anti-inflammatory effects at lower doses than previously reported, as demonstrated in both in vitro and in vivo models.

In an in vivo rat model, NP treatment significantly reduced paw damage and inflammation caused by carrageenan, indicating that pistachio polyphenols may provide protective antioxidant benefits.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Anti-Inflammatory and Antioxidant Potential of Pistachios (Pistacia vera L.) In Vitro and In Vivo. Paterniti, I., Impellizzeri, D., Cordaro, M., et al.[2018]

Pistachio oil and its organic extract significantly reduce the expression of inflammation-related genes, particularly the Ifit-2 gene, in a mouse macrophage cell line, suggesting potential anti-inflammatory properties.

The study found that bioactive compounds in pistachio oil, such as linoleic acid and beta-sitosterol, can replicate this anti-inflammatory effect, indicating that these components may be responsible for the observed gene regulation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Effect of pistachio oil on gene expression of IFN-induced protein with tetratricopeptide repeats 2: a biomarker of inflammatory response. Zhang, J., Kris-Etherton, PM., Thompson, JT., et al.[2020]

A hydrophilic extract from Sicilian pistachios demonstrated significant anti-inflammatory effects in a macrophage model, suppressing key inflammatory markers like nitric oxide and tumor necrosis factor-α without causing cytotoxicity.

Polymeric proanthocyanidins were identified as the main bioactive components responsible for these effects, potentially working through the inhibition of the NF-κB pathway, which is crucial in regulating inflammation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Polymeric proanthocyanidins from Sicilian pistachio (Pistacia vera L.) nut extract inhibit lipopolysaccharide-induced inflammatory response in RAW 264.7 cells. Gentile, C., Allegra, M., Angileri, F., et al.[2021]

Pistachios are rich in nutrients and phytochemicals, including protein, fiber, and polyphenols, which contribute to their antioxidant and anti-inflammatory effects, as shown in various studies.

Regular consumption of pistachios may support cognitive function, improve gut health, and potentially aid in glucose regulation, suggesting they could be beneficial for managing type 2 diabetes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Pistachio Nuts (Pistacia vera L.): Production, Nutrients, Bioactives and Novel Health Effects. Mandalari, G., Barreca, D., Gervasi, T., et al.[2022]

Pistachios are a nutrient-rich nut with a healthier profile than many others, providing monounsaturated fats, protein, fiber, vitamins C and E, and important phytochemicals that may help prevent diseases like cardiovascular disease (CVD), obesity, type 2 diabetes, and cancer.

Research indicates that pistachio consumption positively affects lipid and glucose levels, endothelial function, oxidative stress, and inflammation, while also showing potential benefits for gut microbiota, suggesting they could be a valuable addition to a healthy diet.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Why Should Pistachio Be a Regular Food in Our Diet? Mateos, R., Salvador, MD., Fregapane, G., et al.[2022]

Chronic intake of pistachios in high-fat diet-fed mice significantly reduced inflammation markers such as TNF-α and IL-1β, indicating that pistachios may help combat obesity-related inflammation.

Pistachio supplementation improved gut microbiota composition by increasing beneficial bacteria and reducing harmful ones, which may enhance gut barrier function and contribute to overall health benefits.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Pistachio Consumption Alleviates Inflammation and Improves Gut Microbiota Composition in Mice Fed a High-Fat Diet. Terzo, S., Mulè, F., Caldara, GF., et al.[2020]

Pistacia lentiscus oil demonstrated significant anti-inflammatory effects in a rat model of colitis, improving body mass, reducing bleeding, and decreasing diarrhea compared to control rats.

The oil was most effective when administered preventively before colitis induction, leading to better histological outcomes, such as reduced intestinal erosion and inflammation, suggesting it may modify arachidonic acid metabolism to exert its protective effects.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Preventive and curative effect of Pistacia lentiscus oil in experimental colitis. Naouar, MS., Mekki, LZ., Charfi, L., et al.[2017]

References

1. Switzerland pubmed.ncbi.nlm.nih.gov

The Anti-Inflammatory and Antioxidant Potential of Pistachios (Pistacia vera L.) In Vitro and In Vivo. [2018]

2. Germany pubmed.ncbi.nlm.nih.gov

Effect of pistachio oil on gene expression of IFN-induced protein with tetratricopeptide repeats 2: a biomarker of inflammatory response. [2020]

3. Germany pubmed.ncbi.nlm.nih.gov

Polymeric proanthocyanidins from Sicilian pistachio (Pistacia vera L.) nut extract inhibit lipopolysaccharide-induced inflammatory response in RAW 264.7 cells. [2021]

4. Switzerland pubmed.ncbi.nlm.nih.gov

Pistachio Nuts (Pistacia vera L.): Production, Nutrients, Bioactives and Novel Health Effects. [2022]

5. Switzerland pubmed.ncbi.nlm.nih.gov

Why Should Pistachio Be a Regular Food in Our Diet? [2022]

6. Switzerland pubmed.ncbi.nlm.nih.gov

Pistachio Consumption Alleviates Inflammation and Improves Gut Microbiota Composition in Mice Fed a High-Fat Diet. [2020]

7. France pubmed.ncbi.nlm.nih.gov

Preventive and curative effect of Pistacia lentiscus oil in experimental colitis. [2017]