A popular post by a Malaysian-owned Facebook (FB) page that recommends soaking lettuce leaves in water and honey to “cure” insomnia or improve sleep needs context.
Such claim missed the following facts:
- That some studies on the effectiveness of lettuce leaves to enhance sleep were not done on humans.
- That lettuce soaked in boiling water would not produce enough sleep enhancement substances.
- That the available studies made use of lettuce seeds, while some in combination with other medication and herbs.
“There are very few studies on the effectiveness of lettuce leaves to enhance sleep,” said experts from the Philippine Institute of Traditional and Alternative Health Care (PITAHC) in an email to VERA Files Fact Check.
In fact, most studies are associated with the use of its seeds which contain lactucin and lactucopicrin known as “sleep enhancement substances.”
The image used in the said post can be traced to a viral video on TikTok posted last May 31 by a user account named @shapla_11. As of publishing, it has been viewed by over 1.4 million Tiktok users and the hashtag #lettucewater has reached 33.1 million views.
Public health experts from global technology nonprofit Meedan said lettuce contains a phytonutrient called lactucarium, which “may contain some sedative and calming properties in very large amounts.”
An oft-cited study, published on May 19, 2017 in the Journal of Food Science and Biotechnology, looked into whether seed and leaf extracts from romaine lettuce could “increase the likelihood of sleep activity.”
The combination of the medication and the high concentration of lettuce were thought to shorten the amount of time it takes to fall asleep, and increase the length of time spent sleeping when compared to other lettuces, Meedan’s experts explained.
They noted, however, that the primary study was conducted in mice, “who were heavily sedated with a sedating medication and a romaine extract.”
“A few leaves of lettuce soaked in boiling water would not produce enough of the milky substance from the lettuce stem to aid with sleep challenges.”
The researchers also said “further study for the sleep structure and sleep mechanisms” induced by romaine lettuce extracts is required before they can be used as dietary complements or as natural food antioxidants.
PITAHC told VERA Files Fact Check that there are some international studies that have investigated the use of seeds and leaves as sleep enhancers.
For example, a 2020 study in Traditional Persian Medicine, published in the Journal of Ethnopharmacology, evaluated the benefits of a combination of violet oil, saffron oil, and lettuce seeds oil as a nasal drop among 50 patients with primary chronic insomnia.
While it seemed that the intranasal use of the multi-herbal preparation “can be used to improve chronic insomnia,” it was concluded that future clinical trials with more samples “would shed more light on the efficacy and safety of this medication.”
Despite the limited data on the benefits of lettuce water on humans, health experts said “it is likely not harmful for people to try” such remedy.
The FB post, first uploaded on June 23, continues to circulate online with over 85,000 shares, 19,000 comments, and 18,000 reactions.
My Weekend Plan is an education website and a “daily baking magazine on the Web.” Its FB page, created on July 26, 2015, has 161,800 followers.
(Editor’s Note: VERA Files has partnered with Facebook to fight the spread of disinformation. Find out more about this partnership and our methodology.)