Old wives’ tales are the cautionary tales we tell our children, passing down wisdom through generations. They often blend folklore with pseudoscience, but what does the actual science say? We surveyed clinicians who care for children in primary and secondary care for their favourite tales via the Don’t Forget the Bubbles Discord, which has more than 300 members from around the world (though predominantly based in the UK and Australia). After selecting the most popular, we conducted seven literature reviews, developing PubMed search strategies using MeSH terms and free-text keywords, and performing citation searches on relevant articles. When research was sparse, we broadened our search to Google Scholar and grey literature, to explore the evidence behind these time-honoured claims.
1. Cracking knuckles gives you arthritis
Of all the body’s sounds, older relatives love to warn children about knuckle cracking. But is there any science behind the claim that it causes arthritis? We cracked this myth open.
First, the anatomy. Knuckle cracking collapses the bubbles in synovial fluid, producing that satisfying pop. A case study (with one participant) conducted over a 50-year period compared a left hand that was knuckle-cracked (36 500 times) and a right hand that was not cracked at all.1 There was no correlation between habitual cracking and osteoarthritis.
Two other studies totalling 515 participants also found no link to arthritis,2,3 although reduced grip strength was noted among avid crackers.3
Be warned, however: two cases of ligament injuries from overzealous popping have been reported.4
Bottom line: Knuckle cracking, a satisfying and relatively safe, if noisy, pastime, does not cause arthritis.
2. You will catch a cold if you go outside with wet hair
Children have frequently been warned not to go out with wet hair in case they ‘catch cold’. One explanation is that sinus pain experienced in cold conditions might be mistaken as the beginning of a respiratory tract infection.5
One study showed no difference in colds based on the hair-drying methods of 102 swimmers in winter.6
A 2005 literature review found no significant increase in the risk of contracting a cold because of cold exposure.7 Interestingly, in a study of 180 participants, acute chilling of the feet was found to cause the onset of common cold symptoms in 14%, though the authors did surmise that further studies are needed.8
Bottom line: Hats and hair dryers may be less important than warm socks and wellies in preventing colds.
3. Chicken soup cures common colds
Science suggests there is more to Grandma’s cure-all than meets the spoon. For starters, chicken soup inhibits neutrophil activation,9 meaning it could reduce inflammation.
One study showed that sipping chicken soup increased nasal mucous velocity from 6.9 mm to 9.2 mm per minute, faster than a hot water control.10
In one case report, a man abruptly stopping his chicken soup regimen developed pneumonia,11 solid proof you should take your chicken soup with a pinch of salt (and perhaps some crackers).
It might not be the chicken though. The warm, wet nature of chicken soup might generally help by loosening secretions and maintaining hydration.12
Bottom line: While the science simmers, it seems that a bowl of chicken soup may indeed be a cure for the common cold.
4. Swallowed gum stays in your stomach for 7 years
We found 12 reports of gum causing some sticky situations. These were some of our favourites.
Two 4-year-olds with severe constipation were found to have rectal gum bezoars. On questioning, all four parents admitted using gum as a potty-training prize.13 The same authors reported a 1-year-old with an oesophageal mass of coins and gum. Swallowing your savings is not so savvy.
An adult quitting smoking was investigated for anaemia. Their colonoscopy revealed 30 nicotine gum pieces in the colon.14 Some habits are tough to unstick.
A 40-year-old with vomiting and achalasia had a gastroscopy that unearthed a 5 × 5 cm gum mass with, what the authors described as, ‘a minty aroma’.15
Bottom line: While gum might not stick around for 7 years, it can gum up the works if swallowed excessively.
5. Sitting too close to the television makes you short-sighted
There has been longstanding concern about television causing ‘eye strain’.16 However, there is very little evidence supporting this.17
Although a 1950s survey of over 19 000 children aged 7–14 years concluded that television caused eye strain, their assumptions were short-sighted. They did not account for pre-existing myopia or that the wealthier demographic of television-owning parents might simply have been more vigilant about eye exams.18 Indirect evidence at best; certainly not 20/20 hindsight.
More robustly, a study of 1312 children aged 7–18 years correlated eyesight with watching television. There was no correlation between hours watched and visual disturbance.19
In fact, television has been recommended for amblyopic eye exercises, and to improve diplopia after strabismus operations.17
However, a study of 76 adults watching ultra-high-definition television found that those aged over 50 years, or with a tendency for dry eyes, reported increased ocular discomfort.20
Bottom line: While the jury’s still out, the old adage about television destroying your vision might be more fiction than fact. Keep your distance, but do not lose sight of the bigger picture.
6. Sitting on a cold wall gives you piles
We could not find any evidence to support or refute the claim that sitting on a cold wall causes haemorrhoids. But, as cold surfaces usually cause vasoconstriction, it might be argued that a cold wall should be a cure, not a cause.
Bottom line: Perching on a frosty wall will not give you piles, though it might give you a chilly behind.
7. Squeezing a spot on your nose could cause a brain abscess
TikTok, Instagram, and magazines aimed at teenagers frequently caution squeezing spots on the nose because of the vascular connections in the facial ‘danger triangle’ giving a risk of brain abscesses. However, there are no published case reports about brain abscesses secondary to squeezed acne.
Bottom line: This can safely be dismissed as a myth, though squeezing spots does risk scarring and local infection so cannot be recommended.
Conclusion
These cautionary tales are steeped in cultural lore and parental wisdom. However, they may not always be based in truth. We have explored the evidence, underscoring that, while such traditions hold value, a dose of scepticism often helps separate fact from folklore.
- © British Journal of General Practice 2025
