Cracking your knuckles won't cause arthritis and you CAN eat before swimming: Doctor busts the most common health myths

© Provided by Associated Newspapers Limited There's an obscure pleasure some people get from cracking their knuckles and chances are you've heard doing so can cause arthritis (stock image) With a new health blog launching online every day, diet and fitness myths are spreading faster and wider than ever before.  

So, to cut through the information overload, Sydney-based GP, Dr. Ginni Mansberg, has busted some of the most common health myths she's come across in recent months. 

From whether swimming after eating is bad for you to the famed knuckle cracking debate, Dr. Mansberg addresses some of the most common misbeliefs.

Cracking knuckles won't cause arthritis

Many believe that cracking their knuckles can cause arthritis. Speaking on Sunrise, Dr. Mansberg said this couldn't be further from the truth.

© Provided by Associated Newspapers Limited Sydney-based GP Dr Ginni Mansberg (pictured) recently looked at some of the more commonly-held myths about the human body She said one study had shown those who cracked their necks were more likely to get arthritis in their necks. However, she added, it wasn't clear if the need to crack joints revealed a predisposition to arthritis.

The heart cannot be restarted with an electric shock

Chances are you've seen numerous movies and television shows where a person who is "flatlining" has their heart restarted with an electric shock.

"In fact, you can do more harm than good," said Dr. Mansberg. She explained asystole (flatlining) is a cardiac arrest rhythm with no discernible electrical activity on an EKG monitor.

"It's particular rhythms that do well with shocking. If you have a defibrillator at home it will pick up the rhythm and only shock if it needs to," she added.

© Provided by Associated Newspapers Limited Dr Mansberg said there's nothing to back up the claim that a person shouldn't eat before swimming (stock image) Eating before swimming won't cause cramps

One of the most enduring myths is that eating before swimming will cause cramps. Dr. Mansberg this health myth was based on the belief the body diverted blood to the stomach in order to help it digest food.

She explained a flow of blood away from the muscles would mean you'd struggle to swim if caught in a rip and this may result in drowning. But, the GP said there's no evidence for this belief whatsoever.

"Your body can multitask. It can digest food and swim at the same time."

Shaving will make hair grow back thicker

It's long been thought shaving any part of the body will make the hair grow back thicker. But as it turns out, this couldn't be further from the truth. Dr. Mansberg explained hair is 'javelin-shaped' meaning it is thinner and more pointed at one end.

If you don't shave, what you see is that thin pointy end, but if you cut it in the middle it appears thicker. Backing up her claims, she said a study asked a group of men to shave one leg and not the other for a period of time.

When they were eventually able to regrow the hair, there was no discernible difference between the two legs.   

Sugar won't make kids hyper

Dr. Mansberg said there's nothing to back up the notion sugar makes kids more hyperactive.

"I'm not advocating giving your kids heaps of sugar, I don't think that's a good idea regardless, but no we can blame the hyper on the sugar," she said on the program.

The GP explained over-tired children are just as likely to be cranky and difficult to control. However, a study showed if a parent thinks a child is amped up on sugar, they are more likely to treat them as such.

In 1994, research by the University of Kentucky found parents who thought their children had consumed sugary drinks (even when they hadn’t) tended to rate them as more hyperactive. It’s a self-fulfilling prophecy.