You’re starting to feel under the weather — hopefully it’s just a cold.
You may not feel particularly hungry, but could maybe get some chicken soup down.
But will it make you feel better? There’s an old saying about this, but how does it go again, is it starve a fever and feed a cold, or the other way around?
There are plenty of folk sayings and “tips” about everything from staying healthy to avoiding a hangover.
The only problem is that a lot of folk wisdom about health and nutrition is totally — or at least mostly — wrong.
Here’s the truth behind some of the health claims you might hear.
The myth that MSG is bad for you comes from a letter a doctor wrote to the New England Journal of Medicine in 1968, where he coined the term 'Chinese restaurant syndrome' to describe a variety of symptoms including numbness and general weakness.
But though the doctor blamed these feelings on monosodium glutamate, MSG, the research doesn't back it up. The scientific consensus according the American Chemical Society is that 'MSG can temporarily affect a select few when consumed in huge quantities on an empty stomach, but it's perfectly safe for the vast majority of people.'
And this makes sense -- MSG is nothing more than a common amino acid with a sodium atom added. Eating a ton of food or tablespoons full of the salt could cause the general malaise attributed to the flavour enhancer, and the placebo effect is more than strong enough to account for the negative effects sometimes associated with MSG.
There isn't a whole lot of evidence on this, but most research finds no correlation between caffeine consumption and bone growth in kids.
In adults, researchers have seen that increased caffeine consumption can very slightly limit calcium absorption, but the impact is so small that a tablespoon of milk will more than adequately offset the effects of a cup of coffee.
Interestingly, advertising seems to be largely responsible for this myth too. A breakfast cereal manufacturer named C.W. Post was trying to market a morning beverage called 'Postum' as an alternative to coffee, so he ran ads on the 'evils' of Americans' favourite hot beverage, calling it a 'nerve poison' that should never be served to children.
Some parents say no swimming for 30 minutes after eating, some say an hour, but many of us may remember waiting out the clock before returning to the pool or beach. The theory behind this seems to be that digesting food will draw blood to your stomach, meaning that less blood is available for your muscles, making them more likely to cramp.
Cramps do happen frequently when swimming, but they aren't caused by what's in your stomach. If you do get one, the best policy is to float for a minute and let it pass.
Ever hear someone say, 'keep the gin away from uncle Al, you know how he gets...'?
There are plenty of alcohol related myths out there, and the idea that different alcohols have different effects on you is a big one. Some people claim wine makes them sleepy while whiskey makes them want to argue.
So why do people insist that tequila makes them crazy?
One very strong possibility is that we experience the effects we expect when we drink (or consume most substances). Scientific research going back to the 1960s shows that we 'learn' how to behave while drunk, and that our actual drunken behaviour is a direct reflection of our expectations.
Although many people may become violent while intoxicated, people who have never associated drunkenness with conflict don't show the same behaviour. So by that same token, if we expect that vodka will make us want to sing karaoke, we can perhaps turn that into a self-fulfilling prophecy.
Hydration is very important! But the idea that eight glasses of water is essential is a strange one.
In healthy people, researchers haven't found a connection between fluid intake and kidney disease, heart disease, sodium levels, or skin quality.
People get a lot of their water from foods and other beverages in the first place, but there is a good reason to drink more water. It's a calorie free alternative to other beverages (especially sugary ones like soda or 'sports drinks'), and people who drink water instead of those beverages consume fewer calories overall.
But in general, drink when you are thirsty -- you don't need to count the glasses.
If you decide to wade into this one at the dinner table, we'd recommend calmly explaining that this idea comes from a now thoroughly-debunked (and retracted) study of 12 children that appeared in 1998 in The Lancet and claimed there was a link between the MMR vaccine and autism.
It turned out that study wasn't only flawed, it also contained false information that was necessary to make its point.
Since then, numerous studies that have analysed data from more than a million children have shown that there's no connection between vaccines and autism.
But fears about that connection have persisted, partially spurred on by public figures making false claims about vaccines. This has led to scary diseases like measles coming back and to vaccination rates in some wealthy Los Angeles neighborhoods that are like those in Chad or the South Sudan.
Apples are packed with vitamin C and fibre, both of which are important to long-term health, but they aren't all you need.
And if certain viruses or bacteria get into your system, an apple will unfortunately do nothing to protect you. So go ahead and get that flu shot, even if you eat apples.
Fortunately, this isn't true either.
Cracking your knuckles may annoy the people around you, but even people who have done it frequently for many years aren't any more likely to develop arthritis than those who don't.
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