What's the Difference Between Mold and Mildew?

iStock.com/AndreasReh
iStock.com/AndreasReh

We’re all familiar with colorful spots of something growing in our showers and in other dark, damp areas in our homes, but you may not know what to call it. Is it mold, or is it mildew? What is the difference between the two, anyway?

Both terms refer to fungus, but as it happens, it’s a squares-versus-rectangles situation. Mildew is a type of mold. The term typically describes fungi that grows flat, on surfaces like the walls of your shower or window sills. There are also several types of mildew that are specific to plants—powdery mildew and downy mildew are parasites that grow on certain trees, flowers, and crops, for example. While mold might be a colorful green or black, mildew is typically white.

The word mildew originally came from honeydew, a term for sticky secretions aphids and other insects leave on plants, which people used to think came from the sky, like dew. Eventually, the word came to refer to the mold caused by the fungi that fed on these secretions.

Leaves covered in white powder
Powdery mildew on maple leaves
iStock.com/kazakovmaksim

Most of the household growths we refer to as mold belong to just a few families of fungi species. According to the CDC, the most common indoor molds are Cladosporium, Penicillium, Aspergillus, and Alternaria. Household molds can be a variety of colors, from orange-brown to green to gray to black. (Note that not all mold that is black in color is the more toxic species we call “black mold,” or Stachybotrys.) In contrast to the powdery texture of mildew, molds are typically fuzzy or slimy.

In nature, mold can play an important role in the ecosystem, breaking down dead plants and leaves. In your house, those decomposition abilities aren’t quite so welcome. Mold spores fly through the air, and when they land in moist places, they start to grow—whether that’s on food, your ceiling, paper products, wood, carpet, leather, or elsewhere around your house—and in the process, destroy whatever they're growing on. Unlike mildew, most molds grow down into the surface of its habitat, making them more difficult to remove. In porous materials, mold grows into all the empty crevices, which is why it is often impossible to remove all the mold from ceiling tiles (or soft foods like bread).

Mold growing under a windowsill and near the carpet of a home
Mold growing in a Nashville home following a flood
Martin Grube, FEMA // Public Domain

Getting rid of the unsightly growth in your damp bathroom is more than just a matter of aesthetics. Indoor mold can cause allergic reactions, such as a stuffy nose or itchy eyes, and can lead to infections for people with compromised immune systems. Some people are more sensitive to mold than others, and may experience more symptoms when exposed to it. Generally speaking, though, mold spores are everywhere, so you’re never going to live a totally mold-free life. Spores will come into your home through windows, doorways, ventilation and climate control systems, and via your clothing, shoes, and pets.

But there’s only one way to effectively inhibit mold growth at home: Get rid of the moisture. That means fixing leaks, getting better ventilation, and possibly running a dehumidifier, according to the CDC’s recommendations on mold.

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What Does CPR Stand For?

undefined undefined/iStock via Getty Images
undefined undefined/iStock via Getty Images

The life-saving technique known as CPR stands for cardiopulmonary resuscitation. It's a method that allows oxygenated blood to temporarily circulate throughout the body of a person whose heart has stopped. When the heart ceases beating during cardiac arrest, lungs stop receiving oxygen. Without oxygen, nerve cells start to die within minutes; it can take just four to six minutes for an oxygen-deprived person to sustain permanent brain damage or die.

The cardio part of the phrase refers to the heart, the muscular organ that pumps blood through the body's circulatory system. Pulmonary involves the lungs. People take approximately 15 to 20 breaths per minute, and with each breath you take, your lungs fill with oxygen. Resuscitation means bringing something back to consciousness, or from the brink of death.

We have two physicians, Peter Safar and James Elam, to thank for developing mouth-to-mouth resuscitation in the mid-1950s. In 1957, the American military adopted their CPR method for reviving soldiers. In 1960, the American Heart Association integrated chest compressions, which keep the blood circulating.

Doctors, nurses, dentists, first responders, lifeguards, and some teachers are required to be certified in CPR. But because approximately 85 percent of cardiac arrests occur at home, it’s smart for the average person to know how to perform it, too. In school, you were probably taught CPR by the traditional method of giving 100 to 120 chest compressions per minute (play the Bee Gees’ "Stayin’ Alive" in your head to keep the beat) and mouth-to-mouth resuscitation. Today, the American Heart Association recommends that average people learn hands-only CPR, which simply involves chest compressions. The organization has found that people can be reluctant to administer mouth-to-mouth CPR in an emergency because they're afraid of doing it wrong or injuring the patient. With hands-only CPR, bystanders feel less anxiety and more willingness to jump in. The AHA also notes that hands-only CPR can be just as effective in saving a life. (And any CPR is better than none at all.)

But how many people actually know CPR?

In 2018, a Cleveland Clinic survey found that 54 percent of Americans said they knew CPR, but only one in six people knew that bystander CPR requires only chest compressions. Only 11 percent of people knew the correct pace for compressions. Again, singing "Stayin' Alive" to yourself is one way to remember the pace—though being a fan of The Office can apparently help, too (as one lucky life-saver recently discovered).

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Are Left-Handed People Really More Creative?

Kuzma/iStock via Getty Images
Kuzma/iStock via Getty Images

The left-handed brand has come a long way in the last few decades. The majority of people no longer assume that southpaws are tools of Satan, alight with hellfire. Today’s lefties are surrounded by a far more benevolent glow. We associate left-handedness with intelligence, out-of-the-box thinking, and artistic talent. But are these flattering generalizations backed up by science? Does being left-handed really make you more creative? 

The answer to that is a definitive … maybe.

Scientists have been chipping away at the peculiarities of left-handedness, which occurs in about 10 percent of the population, for a long time. They’ve looked into the purported links between left-handedness and things like mental illness, faulty immune systems, and criminal behavior. They’ve studied whether lefties are better at problem-solving, and if they’re more likely to die young. From all these studies on left-handedness, we can conclude one thing, and one thing alone: science is complicated. 

A handful of studies have found a link between left-handedness and creativity, conferred (some think) by the fact that left-handed folks constantly have to adjust to a right-handed world. Other studies found no link at all. 

Some researchers conclude that lefties are no smarter than righties, while others say that left-handedness comes with a clear intellectual advantage. Is there really a left-handed personality? Are lefties more prone to schizophrenia and learning disabilities? That depends on who you ask. 

But "Are lefties different?" might not even be the right question. Over the last few years, a number of studies have concluded that it’s not which hand is dominant that matters—it’s the degree of dominance. According to researchers, very few people are truly entirely left- or right-handed; it’s more of a spectrum. We use our left hands for some things and our right hands for other tasks. 

These experiments have found that people toward the middle of the spectrum are more flexible thinkers. They seem to be more empathetic and better able to view things from other people’s perspectives. When considering the risks and benefits of any given decision, inconsistent-handed people (as researchers call them) are more likely to focus on the risks, whereas people at the outer edges of the handedness spectrum pay more attention to potential benefits. They may even sleep differently. It seems we’ve been aiming our stereotypes a little too far to the left.

But who knows? This is ever-changing, constantly evolving science. If you’re a lefty who enjoys feeling superior, we’re not going to tell you to tone it down. For all we know, you could be right.

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