Most annoying urban myths debunked – part 4

There are countless urban myths floating around. Some are amusing, some are terrifying and some are just plain weird. But there are also plenty of urban myths that I just find utterly annoying. Most of them are things I’ve believed in myself in the past, but when thinking about it logically realising couldn’t be true. Which is why I find them so annoying!

This is part four – read part 1, part 2 and part 3 here.

7. Don’t reheat rice or you’ll get food poisoning

“Noo! Don’t eat that delicious and healthy oriental fried rice dish! It’s made from reheated rice! It’ll kill you!”

This myth is kind of interesting, as it combines two of my interests – food and microbiology: ”Don’t ever reheat rice or you will get food poisoning”. Apparently, you can only eat rice when it’s freshly cooked. If you leave it to cool and then reheat it, there’ll be hell to pay and a rushed trip to your local hospital’s Accident & Emergency ward.

No. Reheating rice will not make it poisonous. In fact, reheated rice contains fewer available carbohydrates than when freshly cooked, which actually make it healthier if you’re watching you calorie intake. Reheated white rice it as healthy as brown rice; great news for us who don’t appreciate the taste of brown rice. (By the way, the same is true for pasta: reheated pasta is as healthy as the whole grain kind.)

But there is a grain of truth to this myth. Even though the reheating of the rice isn’t the problem, cooked rice that has been stored in room temperature could contain high levels of bacteria. Spores of Bacillus cereus is often found in uncooked rice and they have been known to survive the cooking process. Furthermore, cooked rice has a perfect level of moisture to facilitate bacterial germination and growth. Leave your pot of cooked rice out on the kitchen surface for a day or two, and you could potentially end up with rice full of bacteria-produced toxins. These toxins will survive any kind of reheating (even if the bacteria don’t), which is probably the reason this myth arose in the first place.

So no, reheating rice will not give you food poisoning. However, forgetting to refrigerate your cooked rice might.

8. A clean home is a healthy home

Nowadays, you only have to switch on your television set to be served with adverts promoting soaps, washing-up liquids or disinfectants that will ’kill 99.9% of all known bacteria’. The adverts usually start with outlining how dirty your home really is, and how dangerous it makes it for your defenceless children. As soon as they unwittingly touch a surface their hands would be covered in bacteria. Luckily there is a solution: if you purchase Cleaning Product X you can eradicate those horrible germs and the whole family will be safe!

“Bacteria everywhere! Must. Clean. Again.”

No. First of all, the majority of the bacteria found in our homes are perfectly harmless. In fact, the presence of those harmless bacteria could help keeping any pathogenic bacteria in check by out-competing them.

Secondly, we must assume that some of the antibacterial subustances from these cleaning products will sooner or later enter our bodies, either via food prepared on treated worktops or from our hands washed in antibacterial soap. What will these substances do to our internal bacterial flora? If we constantly reduce the levels of our gut bacteria, surely this will cause problems with our digestion?

Thirdly, we are not defenceless. Our immune systems are perfectly capable to handle most types of bacteria, viruses and fungi found in your home. Actually, by removing most of the germs from our environment we will weaken our immune systems and might even cause it to attack our own bodies instead, leading to autoimmune syndromes like allergies.

And last but not least, what good could come from constantly exposing bacteria to anti-bacterial chemicals? All that will do is to increase the selective pressure for resistant strains of bacteria, and we’ll be left with homes full of much stronger and hardier germs.

Obviously, I’m not saying we should stop washing and live our lives in filth. Keeping clean is a major part of keeping healthy. But trying to keep your homes sterile is not. So please, stop making these annoying commercials!

This is the fourth installment of the Urban myth series. You can find part 1, part 2 and part 3 here. Part 5 is to follow.