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What Causes Eye Floaters?

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Eye floaters — or muscae volitantes, Latin for “hovering flies" — are those tiny, oddly shaped objects that sometimes appear in your vision, most often when you’re looking at the sky on a sunny day. They look like spots, or a squishy little amoeba, and drift aimlessly around in your field of vision. Try to get a fix on one, though, and it seems to disappear.

Floaters aren’t just optical illusions. You’re really seeing them, and they’re actually in your eye, not just on it or in front of it. The weird little squiggles are pieces of the vitreous humor, the fluid that fills the eye, breaking off and then floating about in your eyeball.

A little gross, I know, but completely normal. The vitreous humor fills the gap between your retina and lens and helps maintain the round shape of your eye. It’s made up of water bound up in a little hyaluronic acid and collagen. When you’re young, it’s thick and gel-like, but as you age, the hyaluronic acid network breaks down and releases the trapped water molecules. As this happens, the core of the vitreous humor becomes more watery and little bits of undissolved gel break off and slowly drift around. When light passes through the eye, the shadows of these pieces are thrown up on your retina and you perceive them as floaters.

A Closer Look

Since floaters, well, float, their paths generally follow the motion of the eye. This makes looking right at them difficult, and when you shift your gaze towards them, they often move and stay at the edges. They don’t always float, though, and many of them will sink towards the bottom of the eyeball. To get a good look at them, just lie down looking up at a clear sky. Some of the floaters will settle near the fovea, a small area that sits at the back center of your eye and is responsible for your sharp central vision. The lack of movement and the even, textureless background makes it easy to scope them out and watch the blobs bob around a little.

For the most part, floaters are nothing to worry about — just a sign that you’re not a kid anymore. The sudden appearance of a lot of floaters combined with the onset of other eye weirdness — like flashes of light or blurriness or loss of peripheral vision — could indicate a problem, though. Sometimes, floaters are a symptom of the vitreous humor pulling away from the retina, a retinal tear, or the abnormal growth of blood vessels in the eye. If your floaters cross the line from curiosity to nuisance, it’s time to give the eye doctor a call.

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Big Questions
What Are Carbohydrates Used for In Our Bodies?
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What are the carbohydrates used for in our body?

Ray Schilling:

Carbs are varied. There are complex carbohydrates that are absorbed slowly and you hardly get an insulin reaction. On the other end of the spectrum there are refined carbs like sugar, which are rapidly absorbed in the gut and to which the body reacts swiftly with an insulin reaction to lower high blood sugars.

Generally speaking all carbs are broken down into glucose and absorbed in the gut. Glucose is the fuel that is metabolized inside the cells in the mitochondria to give us energy. This is particularly important in the brain, which lives solely by glucose as its energy supply, but our muscles, our heart, our liver, and kidneys are all very rich in mitochondria for the metabolism of glucose.

But there is a dark side to refined carbs that we need to know about: When all our glucose storage spaces in the liver and the muscles are full (glycogen is the storage form of glucose), then the liver starts processing glucose. With our sugar consumption having spiraled upwards in the last 183 years, this surplus sugar metabolism is causing more and more problems.

The liver produces triglycerides from the extra sugar and LDL cholesterol, the bad cholesterol. This causes hardening of the arteries and causes heart attacks, strokes, and high blood pressure.

We need to come to our senses and cut out processed foods (which have extra sugar in them), switch to a Mediterranean diet and only consume complex carbs, contained in legumes, vegetables, and fruit. It is also recommendable to cut out starchy foods with a glycemic index of higher than 55 in order to bring our liver metabolism back to normal (normal triglyceride and LDL cholesterol production). This will mean cutting out pasta, potatoes, rice, bread, and muffins.

If you're wondering what kind of recipes you could follow, I have included one week’s worth of meals in this book: A Survivor's Guide To Successful Aging: With recipes for 1 week provided by Christina Schilling.

This post originally appeared on Quora. Click here to view.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

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Big Questions
Why Do Cats Freak Out After Pooping?
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Cats often exhibit some very peculiar behavior, from getting into deadly combat situations with their own tail to pouncing on unsuspecting humans. Among their most curious habits: running from their litter box like a greyhound after moving their bowels. Are they running from their own fecal matter? Has waste elimination prompted a sense of euphoria?

Experts—if anyone is said to qualify as an expert in post-poop moods—aren’t exactly sure, but they’ve presented a number of entertaining theories. From a biological standpoint, some animal behaviorists suspect that a cat bolting after a deposit might stem from fears that a predator could track them based on the smell of their waste. But researchers are quick to note that they haven’t observed cats run from their BMs in the wild.

Biology also has a little bit to do with another theory, which postulates that cats used to getting their rear ends licked by their mother after defecating as kittens are showing off their independence by sprinting away, their butts having taken on self-cleaning properties in adulthood.

Not convinced? You might find another idea more plausible: Both humans and cats have a vagus nerve running from their brain stem. In both species, the nerve can be stimulated by defecation, leading to a pleasurable sensation and what some have labeled “poo-phoria,” or post-poop elation. In running, the cat may simply be working off excess energy brought on by stimulation of the nerve.

Less interesting is the notion that notoriously hygienic cats may simply want to shake off excess litter or fecal matter by running a 100-meter dash, or that a digestive problem has led to some discomfort they’re attempting to flee from. The fact is, so little research has been done in the field of pooping cat mania that there’s no universally accepted answer. Like so much of what makes cats tick, a definitive motivation will have to remain a mystery.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

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