Some old wisdom remains useful today. Salt water gargles can still help your sore throat, lavender can still help you sleep, and aloe will almost always soothe a sunburn. But sometimes old-fashioned health tips don’t stand the test of time, and can actually cause harm if followed.
It’s hard to believe, but according to Dr. Robert Kravetz, MD, a clinical professor in Internal Medicine at the University of Arizona College of Medicine in Phoenix, people used to believe that urine could whiten teeth and smoking cigarettes could fight off a cough.
“We have so many medicines today, but years ago, there was very little available. That’s why people would use these various products,” Kravetz says. “When there isn’t a beneficial therapy for something, people will try anything.”
Kravetz says that, as the years go by, it’s only natural that we learn more about medicines, and readjust our perception of which ones are actually effective.
“In the future, some of the things that we do today are going to be thought to be very [outdated] and they’ll say ‘how could doctors do that?’” Kravetz says.
To help you parse through which old-fashioned health tips should be retired, we spoke to experts about pieces of classic advice that are actually harmful.
1. Eating Carrots Will Help Your Vision
This is a tip that has some basis in the truth, but can be detrimental if taken too far.
“It’s true that carrots do contain vitamin A, which can help us to maintain better vision in darker conditions, and contribute towards healthy tissue development and a better working immune system,” Dr. Daniel Atkinson, clinical director at Treated.com, tells Bustle.
But he warns that too much vitamin A can cause problems. “Some research has shown that over time, high levels of vitamin A can lead to osteoporosis, a condition where our bones become weaker and more prone to breaking,” Atkinson says.
Carrots are absolutely healthy in moderation, but you should try to vary your vegetable intake.
2. Alcohol Will Help You Get To Sleep
You might think that a glass of wine before bed will help you sleep, but the truth is more complicated.
“The subject is a double-edged sword,” Atkinson says. “While alcohol makes it easier to get off to sleep straight away, it will ultimately disrupt sleep over the course of the night.”
While pre-bedtime drinks may help you in the short-term, you’ll likely wake up feeling less well-rested.
3. Using Cough Syrup For Coughs
Common knowledge says that when you have a cough, you should turn to cough syrup. However, this classic remedy may not be as effective as you think.
“The real benefits of cough syrup have been called into question in recent years, with some researchers saying that there is little evidence to suggest they have that much of a positive impact,” Atkinson says. “Some experts even think that when someone uses cough syrup and their cough clears up, it’s likely their cough would have cleared up anyway, with or without using syrup.”
Atkinson says that, while taking cough syrup likely won’t cause any harm, it probably won’t fix your cough either. He recommends going to the doctor if your cough lasts more than a week, because there may be an underlying cause that needs to be treated.
4. Stretching Before You Exercise
Many people consider stretching before any exercise to be a requirement; people often think that pre-activity stretching will prevent injury and help their performance. It turns out that stretching only helps in some cases.
“If you’re doing a yoga class or ballet, or another type of activity that requires flexibility, then stretching should be considered an essential part of your warm up routine,” Atkinson says. “If you’re participating in an activity or sport that requires speed and strength, stretching will help your joints and muscles to feel looser, but it won’t necessarily benefit you.”
For speed and strength sports, Atkinson says it’s probably better for your pre-workout routine to get your heart rate up, like jogging in place.
5. Starving A Fever
There is a popular saying that you “starve a fever, feed a cold,” which basically means that eating less will help alleviate a fever. Atkinson believes the origins of this tip come from the fact that when you eat, your body temperature goes up slightly.
“In actuality, our bodies need nutrients and hydration when they’re fighting off a cold or a viral infection. So really, when we’re feeling under the weather, it’s best to drink plenty of water and continue to eat as healthy and balanced a diet as possible,” Atkinson says.
6. Applying Heat After An Injury
After an injury, it’s common knowledge to apply a heating pad. However, this may not be as effective as you think and can potentially cause more damage.
“If you’ve suffered a recent injury, inflammation to the damaged tissue is likely to follow,” Dr. Thanu Jey, clinic director at Yorkville Sports Medicine Clinic, tells Bustle. “Although heat feels good and loosens up stiff tissues, it actually promotes an increase in inflammation which can lead to more stiffness, pain, and mobility loss.”
With so many health tips out there, it’s hard to know which ones are actually correct. Just because something has been repeated for years, doesn’t mean that it stands up to the scrutiny of modern science. Knowing which tips to not follow can help you make the best decisions for your health.