When it comes to the annoying, burning sting of nettle, nothing seems to soothe the pain quite like a sorrel leaf.
However, scientists now say it would be just as good to rub the bite with salad.
A research published today in the journal Journal of Emergency Medicine They found that sweet lettuce leaves were equally effective in reducing the discomfort caused by nettle stings.
In one trial, two-thirds of participants could not tell the difference between being treated with a sorrel leaf and being rubbed with a bit of lettuce.
Dr Rajendra Raman, consultant in emergency medicine at Victoria Hospital, Kirkcaldy, told MailOnline: “If someone wants to rub a leaf and they don’t have lettuce, then lettuce is a reasonable option as it’s definitely not toxic.”
Scientists now claim that if you are stung by a nettle, using a lettuce leaf could be just as good as a sorrel leaf at reducing the pain.
The characteristic burning sting associated with nettles is caused by the hundreds of microscopic needles called trichomes that cover the plant.
When you touch these needles, they break and release a stream of chemicals, including histamine, acetylcholine and serotonin.
Traditionally, the cure for the resulting rash and stinging sensation is said to be to rub a sorrel leaf, known by its scientific name rumex obtusifolius, over the affected area.
As researchers point out, this idea dates back at least 600 years and first appears in the works of Geoffrey Chaucer, sometimes called the father of English literature.
Search the Internet and you’ll find a wide range of theories about why the leaves work, from neutralizing the acid in nettle stings to containing natural antihistamines.
However, researchers believe it is simply the cooling sensation of the plant sap drying on the skin that causes the perceived healing effect.
Researchers say it is only the cooling of the plant’s sap that causes the pain to reduce and any large leaves would work, as sorrel leaves (pictured) often grow near nettles and have become a traditional cure.
If this is true, then there is nothing special about sorrel leaf and a lettuce leaf should be able to do the job just as well.
So when you’re out walking in the woods this summer, you might want to bring lettuce with you in case you encounter bites, the findings suggest.
In the paper, Dr. Raman and colleagues write: “Any large, fresh, nontoxic leaf would do, and sorrel may have become the preferred leaf simply because it grows in similar habitats to nettle.”
To test the purported healing properties of sorrel leaves, researchers conducted a small trial involving nine healthy emergency physicians.
Each participant was asked to rub a freshly picked nettle 10 times on a marked area on each of their forearms before being blindfolded.
To ensure there was no bias in their perception of the treatment, each participant rolled a dice while blindfolded to determine how the plants would be administered.
If an odd number came up, two sorrel leaves were rubbed on the area for 60 seconds on the right arm and two lettuce leaves on the left arm for 60 seconds.
If an even number came up, the application was reversed: sorrel leaves on the left arm and lettuce on the right arm.
Researchers treated participants’ nettle stings with either a sorrel leaf or a leaf of sweet lettuce. Two-thirds of participants could not tell the difference between the two treatments (file image)
After application, participants were asked which arm they thought had been treated with sorrel leaves and which with lettuce.
They were asked to rate their discomfort on a scale of one to five.
The score was monitored until symptom resolution, a measure the researchers called the insult to complete cure, or “ITCH,” score.
The researchers also recorded the number of visible “wheals” (the reddish welts caused by nettles) that were visible on the forearm.
This measure was cleverly named Observable Urticaria Score/Wheal Count, or “OUCH” for short.
While Dr. Raman is keen to point out that this study was intended to be more of a team-building exercise for the research group, the results suggest that sorrel leaves provide little help.
Three of the participants correctly indicated which arm had been treated with dock, three were incorrect, and three were completely unable to say which treatment had been applied.
The researchers found that there was almost no significant difference in discomfort (measured as the ITCH score) whether the person was treated with a sorrel leaf or a lettuce leaf.
While participants’ “ITCH” scores decreased over time, what they received did not make a statistically significant difference: Sorrel leaves only edged out lettuce by one point.
Similarly, participants experienced nearly identical OUCH scores regardless of whether they had been treated with lettuce or sorrel.
“It’s possible that the rubbing action itself, or perhaps the cooling effect of the sap evaporating from a crushed leaf, may also help relieve the sting,” says Dr. Raman.
While the researchers did not include an untreated control in this study, Dr. Raman suggests that using either leaf is unlikely to impact the duration of discomfort.
Dr Raman says: ‘I honestly can’t recommend rubbing anything on nettle stings as there is no scientific evidence that it helps.
The researchers suggest that the pain would likely have decreased over time regardless of whether any leaves had been used, but that the placebo effect may still help people feel better if they have been stung.
“Most likely the discomfort will simply go away regardless of the rub against the lettuce or turnip.”
However, that solution might not seem like a particularly satisfying answer if you happen to be stung by a nettle.
In their paper, the researchers note that children in particular “do not view doing nothing as an acceptable option when they are in pain.”
While Dr. Raman says that “gentle reassurance and time” are probably the only treatment for a child with nettle stings, that doesn’t mean using a sorrel or lettuce leaf is necessarily a bad idea.
Whether you use dock leaves or lettuce to treat bites, it’s likely that the placebo effect is at least partly responsible for making you feel better.
Given how powerful the placebo effect can be, the lack of any real medicinal qualities might not stop this ancient cure from working and the action could provide some much-needed comfort.
Ultimately, Dr Raman says: ‘Rubbing sorrel on nettle stings is a popular children’s remedy that many people love, and is a fairly harmless thing to do.
‘While I wouldn’t recommend scrubbing the dock, I wouldn’t actively advise against it either.’