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Achoo! What does your, ah, snot say about you?

You might be wearing the tell-tale colors of a cold: Your nose is dripping a clear liquid, and the skin near your nostrils is red from sniffling and sneezing. 

A doctor's exam may find the lining of your nose and throat is inflamed and red. And you could have white patches on your sore tonsils. 

But what about the gross gunk clogging up your nose, throat, and lungs? Can the shades of your secretions -- mucus and phlegm -- tell you anything about how long you'll be under the weather or what kind of bug you have? 

Dr. Stacey Tutt Gray is a sinus specialist at the Massachusetts Eye and Ear Infirmary in Boston, and she says it's not unusual for her patients to bring in their mucus-covered tissues to show her what's coming out of their bodies. So Gray is quite familiar with these secretions and her color-inspired last name makes her an ideal expert to explain their various hues. 

But first she points out that mucus is a liquid gel made up of mucin, a protein, and infection-fighting substances. It acts as a protective blanket over the lining of your nose, and the sticky substance can help trap and clear dust, allergens, bacteria, and viruses. 

You make roughly a quart of clear, thin mucus a day, which you usually just swallow. But snot production often cranks up, thickens, and discolors when you catch a cold, have allergies, or get an infection. 

Phlegm is also mucus that's coming from the chest and lungs. Technically, doctors call it sputum. Most people don't normally have phlegm, says Gray, but the lining of the airways has mucus in it to keep the lungs clear. 

A rainbow of mucus and phlegm
As far as color goes, mucus is typically clear. But when the immune system sends white blood cells into the nose to fight off infection, they contain a greenish enzyme that shades the substance yellow or green. These are the same tones mucus takes on when it dries and clumps into boogers.  

Red- or brown-tinged snot could occur when tiny blood vessels in your nose break from frequently blowing it. Black mucus can come from the noses of smokers or people who work in coal mines or dusty environments.

The phlegm palette is similarly multicolored to mucus with clear or white sputum being normal, yellow or green hues from frequent coughing, and red or brown shades from blood that's new or old. If you're seeing a lot of blood in phlegm, give your doctor a call. 

To thin down mucus or loosen phlegm, drink plenty of hot or cold liquids, and take a hot shower or inhale steam. Nasal rinsing with warm water can also help flush out congestion to make breathing easier. 

Gray says she is often asked by her patients with sinus trouble whether the color of mucus means a person has a bacterial infection and if they need an antibiotic. "The color in and of itself doesn't necessarily mean anything," she explains.

 A physician will determine whether an illness is viral or bacterial, an allergy or a sinus problem based on what a patient is saying about their other symptoms -- fever, body aches, nasal congestion, how long they've felt this way -- not just the color of mucus.  

So if you have a cold, you might see a rainbow of gook from your nose and chest. But it doesn't tell you much and it's usually nothing to worry about.

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Bettini

Just LOOK AT IT.

As American cyclist George Hincapie pedals his way toward a record-tying 16^thTour de France that started July 2, it looks as though his brain is escaping from his leg.

Actually, he’s suffering from an unsightly case of varicose veins, says Dr. Walter M. Whitehouse, Jr., a vascular surgeon and Medical Director of Restoration Vein Care in Ann Arbor, Mich. In Hincapie's case, it's likely caused by his hours and hours of sitting on his bike. Sitting or standing for long periods can put pressure on the veins and cause them to bulge.

“These are the ugliest varicose veins I’ve seen in awhile,” he says. “They are more severe than the typical patient. I’ve seen bigger, but these are just a huge mass that are clumped together.”

Varicose veins indicate veins are blocked or pressured and fail to function well enough to carry blood back to the heart. When that happens, vein walls stretch and people can end up with scary-looking legs like Hincapie’s that can ache, swell and cramp.

Whitehouse, also a surgeon at St. Joseph Mercy Hospital in Ann Arbor, Mich., says upon first glance, Hincapie, 38, may need two procedures, one that uses radiofrequencies to collapse some veins, a second to remove the large mass.

 “I’ll bet he doesn’t have any symptoms,” says Whitehouse, “because if he did, he would have done something about it.”

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Warner Bros.

We know, Ed Helms. We're shocked, too!

By Bill Briggs

We’re all grown-ups here.

Kind of.

So why have so many “Bridesmaids” viewers cringed with laughter while watching the bride (Maya Rudolph) and her girlfriends -- bedecked in designer dresses -- suddenly erupt in a food-poisoning-induced storm of vomit and diarrhea? (Pity that poor -- once-white -- wedding gown).

Why, in "The Hangover Part 2," will packs of theatergoers today simultaneously grimace and grin at the glimpse of a young man’s severed ring finger -- still wearing a Stanford class ring?

And why, in 2007's “Knocked Up,” did some of us wince and giggle when we saw a baby’s head crown from Katherine Heigl’s ladyparts as she screamed, “Get out!” to a horrified dude who had peeked into her birthing room?

Those scenes put the gag in -- well -- gag. But many of us roared despite our repulsion. What are we, like, 8 years old?

Why do disgusting or shocking movie moments still make some of us cackle till we cry?

According to two experts -- one a researcher, one a comic -- there’s psychology behind that crude comedy.

“Humor is elicited by the perception of something that seems to be unsettling, threatening, wrong, scary or anger-inducing,” said Peter McGraw, assistant professor of marketing and psychology at the University of Colorado, Boulder. “There’s a wonderful quote by Mark Twain that sums it up nicely: ‘The secret source of humor is not joy but sorrow. There is no humor in heaven.’ ”

Last August, McGraw co-authored a study examining why we laugh at images we consider to be morally wrong. By asking his test subjects to read offensive scenarios -- then tweaking those descriptions to see if the subjects still found them humorous -- the researchers developed their “benign violation theory.”

“Of course, things that are wrong usually make us upset. So at the same time that something is seen as a violation, it also has to be seen as benign -- that it is, in some way, OK or acceptable,” McGraw said.

That benign aspect is fueled, McGraw said, because the situation has “psychological distance” -- it’s happening to someone else, or it happened a long time ago, or that it’s so absurd, it seems obviously contrived. (This is where the old saying, "Tragedy plus time equals comedy," applies.)

Is there a demographic that seems most immune to insult and who, therefore, laughs harder at the raunchiest material?

“Young men seem to be pretty impossible to offend,” McGraw said. “As a result, a lot of things that everybody finds to be violations, they find to be benign violations.”

“It’s the frat humor,” agreed comedian Alonzo Bodden. “It all goes back to ‘Animal House’ and ‘Stripes.’

“When it’s done well, it’s funny,” Bodden said. “It’s funny because it’s so totally inappropriate.”

Bodden agrees with McGraw’s “benign violation theory.” But as a man who stands alone on stage seeking laughter, he also understands that what’s hilarious to one person, can just seem stupid to another.

“When it’s predictable or too over-the-top,” Bodden said, “when the (filmmaker or comedian feels they) have to make it so much wilder and more ridiculous, now it’s not funny anymore.”

To help draw his scientific conclusions, McGraw and his co-author, Caleb Warren, asked 36 participants to read the description of a violation. Some were aghast at the passage. But most were amused – because, to them, it seemed benign. 

The scene? A man rubs his genitals against a kitten -- which "purrs and seems to enjoy the contact."

See. Made you laugh. Well, some of you.

What's your favorite gross-out scene from a movie? Or -- can you think of a movie that went a little too far? Leave a comment telling us the movie and the scene.

Bill Briggs is a frequent contributor to msnbc.com and author of “The Third Miracle.”

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