Did you know that over a third of American adults aren’t getting enough sleep, according to data from the Centers for Disease Control and Prevention (CDC)?
The CDC recommends that adults get at least seven hours of sleep per night for optimal health; however, many Americans are falling short of this goal – especially those of us who live with sleep disorders like insomnia, narcolepsy, sleep apnea, or restless legs syndrome.
Not only does insufficient sleep increase the risk of developing chronic conditions like type 2 diabetes, heart disease, stroke, and hypertension; it also takes a toll on metabolism, weight, memory, attention span, stress levels, and mental health, among other factors.
And when it comes to sleep, the quality matters just as much as the quantity. Signs of poor sleep quality include trouble falling asleep, repeatedly waking up during the night, and feeling tired even when you do get the recommended amount of sleep.
So, how can we improve our sleep? In addition to the usual sleep hygiene tips like limiting caffeine intake and shutting off electronic devices at least 30 minutes before bed, maintaining a healthy diet that’s rich in whole foods can also help – and one nut has been particularly showing promise as of late.
Walnut Intake and Sleep
According to a study recently published in Food & Function, eating 40 grams (or about 1.5 ounces) of walnuts each day could potentially help improve sleep quality and reduce daytime sleepiness in healthy young adults.
An interdisciplinary research team at the University of Barcelona discovered that the melatonin levels measured in the evening urine samples of participants who consumed the walnuts daily for four weeks were significantly higher than those who did not.
In addition, the participants who consumed walnuts daily fell asleep 1.3 minutes faster than the control group on average. While that isn’t exactly a massive difference, their overall sleep quality scores also improved, and they reportedly experienced less daytime sleepiness as well.
According to the researchers, walnuts contain a unique combination of nutrients that are known to have sleep-enhancing properties, including melatonin, tryptophan (a precursor to melatonin), magnesium, and various types of vitamin B.
While the study’s results are promising, they should be taken with a grain of salt, as more research is needed to form a definitive conclusion – and it’s also worth mentioning that the study itself was funded by the California Walnut Commission as well.
In an interview with The Food Institute, Dr. Paul Muchowski, Ph.D., a UCSF-trained neuroscientist and the founder of Defined Research, Inc., also highlighted the fact that the study was open label – as opposed to placebo controlled – meaning that the participants knew the research team was measuring the effects of their increased walnut intake on their sleep, which could impact its results as well.
“Investigators tested a natural substance (walnuts), and it appeared to improve some subjective sleep metrics. The data are promising enough to perform a placebo-controlled study in the future. In the absence of a placebo control, it is impossible to determine the validity of the findings,” Dr. Muchowski told FI.
Other Health Benefits of Walnuts
While the relationship between walnuts and sleep remains inconclusive, you might want to consider increasing your intake either way, as walnuts are packed with vitamins, antioxidants, omega-3 fatty acids, and other nutrients, which can help:
- Lower LDL (or “bad”) cholesterol levels
- Reduce chronic inflammation markers
- Prevent cancer and cardiovascular disease
- Improve gut health and even cognitive function
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