Top medical myths that even doctors believe
Indiana University School of Medicine researchers, Dr. Vreeman and Dr. Carroll, explored some commonly held medical beliefs or rather medical myths. The research, entitled “Medical Myths Even Doctors Believe” was published in the British Medical Journal. The researchers extensively searched medical literature and found no evidence to support these myths, but many doctors believed them. So here are few of the most common medical myths that even doctors subscribe to.
- People should drink at least eight glasses of water a day
“There is no medical evidence to suggest that you need that much water,” said Dr. Rachel Vreeman, a pediatric research fellow at the university. Vreeman thinks this myth can be traced back to a 1945 recommendation from the Nutrition Council that a person consume the equivalent of 8 glasses (64 ounces) of fluid a day. Over the years, “fluid” turned to water. But fruits and vegetables, plus coffee and other liquids, count too!
- People only use 10 percent of their brains
MRI scans, PET scans, other imaging studies and metabolic studies show no dormant or non-functioning areas of the brain. Viewing individual neurons or cells also, revealed no inactive areas. The myth probably originated with self-improvement instructors in the early 1900s who wanted to convince people that they had not yet reached their full potential.
- Shaved hair grows back faster, coarser and darker
A 1928 clinical trial compared hair growth in shaved patches to growth in non-shaved patches. The hair which replaced the shaved hair was no darker or thicker, and did not grow in faster. More recent studies have confirmed this.
Carroll and Vreeman explain that when hair first comes in after being shaved, it grows with a blunt edge on top. Over time, the blunt edge gets worn so it may seem thicker than it actually is. Hair that’s just emerging can be darker too, because it hasn’t been bleached by the sun.
- Fingernails and hair grow after death
Most physicians queried on this one initially thought it was true. Upon further reflection, they realized it’s impossible. Vreeman clarified this and said, “As the body’s skin is drying out, soft tissue, especially skin, is retracting. The nails appear much more prominent as the skin dries out. The same is true, but less obvious, with hair. As the skin is shrinking back, the hair looks more prominent or sticks up a bit.”
- Reading in dim light ruins your eyesight
The researchers found no evidence that reading in dim light causes permanent eye damage. It can cause eye strain and temporarily decreased acuity, which subsides after rest.
