Can Pistachios Improve Sleep? Review Highlights Vitamin B6, Magnesium and Melatonin
A new review published in Nutrition Research Reviews examines how nutrients and bioactive compounds in pistachios may influence sleep biology. The authors suggest that pistachios are a promising food for sleep research, but emphasize that clinical trials are still needed.
Why researchers are studying pistachios and sleep
“Pistachios are attractive for sleep research because they bring together in one whole food several nutrients and plant compounds related to sleep physiology,” said lead author Marie-Pierre St-Onge, Ph.D., director of the Center of Excellence for Sleep and Circadian Research at Columbia University Irving Medical Center.
“Rather than focusing on a single ‘sleep nutrient,’ this review provides a rationale for studying how a complete pistachio food matrix affects sleep-related pathways.”
Dr. St-Onge and her colleagues say pistachios stand out among nuts because they contain several nutrients and compounds connected to sleep-related processes.
Pistachio nutrients linked to sleep biology
One ounce, or 28 grams, of pistachios provides approximately 38% of the daily intake of vitamin B6. The body uses vitamin B6 to produce serotonin and GABA, a calming neurotransmitter.
Pistachios also provide magnesium, fiber, polyphenols and tryptophan. Tryptophan is an amino acid that helps the body produce melatonin, the hormone that signals nighttime.
Pistachios also contain melatonin, which is produced by the plant itself.
What the evidence says about nuts and sleep quality
The review notes that diets rich in nuts, including the Mediterranean diet, are associated with better sleep quality. Observational studies have also linked higher intakes of magnesium and fiber with better sleep quality.
Studies of other melatonin-rich foods, including tart cherry juice and tomatoes, have reported increased melatonin production and improved sleep. However, these findings do not establish that eating pistachios improves sleep.
Can pistachios improve sleep? More research is needed
No clinical trials have investigated pistachio consumption and sleep. Much of the available evidence comes from studies of individual nutrients, supplements or population surveys, which cannot prove a causal relationship.
Evidence concerning vitamin B6 is mixed. Some supplement trials have found no benefit in people who do not appear to be deficient in vitamin B6. Studies of magnesium have also produced mixed results.
The review additionally highlights uncertainty about the melatonin content of nuts. One analysis of American pistachios estimated the amount at approximately 18.7 micrograms per ounce, while other sources report an average of only 0.074 micrograms.
According to the researchers, melatonin levels may vary depending on the pistachio variety and processing method. It has also not been directly tested whether the body absorbs these compounds from nuts.
Researchers call for pistachio sleep trials
The authors call for randomized controlled trials examining pistachio consumption and sleep in diverse populations.
“A well-designed human trial will help determine whether the unique combination of nutrients and bioactive compounds contained in the pistachio food matrix produces measurable changes in melatonin, sleep quality, sleep duration and other sleep outcomes,” said Dr. St-Onge.
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Ashley Mixon et al. 2026. Exploring the role of pistachio nutrients and bioactive components in sleep health: A narrative review. Nutrition Research Reviews 39: e29; doi: 10.1017/S0954422426100511
Source: www.sci.news