Pistachios contain compounds involved in sleep regulation. Researchers from Spain and the U.S. set out to determine whether they contain enough of these compounds to have a noticeable effect.
The findings were published in the journal Nutrition Research Reviews.
How pistachios may affect sleep
Pistachios contain tryptophan, an amino acid involved in producing serotonin and melatonin. The latter helps the body regulate the sleep-wake cycle.
The review suggests that a 28.3-gram serving of pistachios contains around 71 mg of tryptophan. These nuts also contain vitamin B6 and magnesium, which contribute to the normal functioning of the nervous system.
These compounds alone do not mean pistachios significantly improve sleep. The effect also depends on how nutrients are metabolized and how they reach the brain.
Melatonin content in pistachios
Researchers also examined phytomelatonin, the plant form of melatonin. Their findings indicate that one serving of pistachios contains between 0.074 and 18.7 micrograms.
The range is quite wide, so it is currently impossible to determine precisely whether this amount is sufficient to affect sleep.
The optimal dose of melatonin for improving sleep has not been universally established either, and the findings of food studies cannot be directly equated with the effects of melatonin supplements
Pistachios alone won’t treat insomnia
The review does not allow for determining which serving of pistachios could improve sleep. There is also no evidence that pistachios before bed have the same effect as melatonin.
Pistachios are of interest for further research because they contain a combination of nutrients and plant compounds. The authors believe more research is needed.
Although the topic is interesting, there is insufficient evidence to treat insomnia with pistachios. If sleep problems persist, it is best to consult a doctor.