There are four possible reasons why some people fart more than others: They eat a lot of carbohydrates; they swallow air when they eat; the bacteria in their intestines are more efficient in turning carbohydrates into gas; or, conversely, the bacteria in their intestines don’t consume carbohydrates efficiently, and therefore produce gas.

Levitt says an average male fart is made up of about 110 milliliters of gas (almost half a cup), with 80 milliliters for a woman’s (a third of a cup). That adds up to a lot of gas — 38 ounces during a single day for men, 27 ounces for women. Although some women claim they never fart, Levitt says that’s not true. They just fart less because they are smaller.

Gassy food is gassy food for everyone, says Levitt, with a crucial caveat. Some people are able to absorb and tolerate the gas they produce better than others. The single most gas-producing food for most everyone, Levitt says, is — no surprise — baked beans. The musical fruit is made up entirely of simple carbohydrates, which are not absorbed in the intestines. Once inside the intestines, the sludge that was once beans is broken down by bacteria and enzymes, and then ferments. In that process, the thick, gooey substance can produce potent gases that have nowhere to go but down — and out, thank goodness.

Out is important. While Levitt says he has never treated someone who held a fart in too long, there are dangerous side effects (including dizziness and headaches). Your colon becomes bloated, and theoretically, the methane and other lethal gases could add enough toxins to your blood to poison you. Levitt does not recommend holding in farts.

Besides beans, vegetables (especially broccoli, brussels sprouts, cabbage and cauliflower) are also gas producers, as are grains and fiber. (Pumpernickel, the dark-grain bread, means “goblin that breaks wind” in Old German.) In fact, some of the healthiest foods, touted as anodynes for cancer and heart disease, are the foods that produce the most gas.

But what if you don’t eat lots of veggies and carbs and you still exceed 10 explosions a day on the fart-o-meter scale that Levitt says is normal? There could be several reasons:

Drinking too many carbonated beverages. The fizz in most carbonated beverages comes from carbon dioxide, which is dissipated by the time it reaches your intestines. But many soft drinks contain fructose, a sugar the intestines have a difficult time absorbing, thereby causing flatus, the medical term for farts (which comes from the Latin meaning “the act of blowing”).

Drinking through a straw. If you sip air when you swallow, then the air has to come out some way, often through your butt.

Eating too fast, and eating too much fast food. Chew your food slowly. The act of eating quickly tends to induce the diner to take in air, thereby bloating the colon, as well as turning the air inside deadly.

Chewing gum. When you chew gum, you swallow air, and that means more of the above.

Not enough exercise. Exercising helps the body absorb gases in the colon, thereby dissipating them by the time they reach your anus. If you happen to fart while you are exercising, particularly in a health club, it’s usually not so bad because most people wear headsets and listen to music, which tends to obscure the sound. As for smell, workout places often are venues of assorted bodily odors, so run-of-the-mill farts often go undetected, particularly if you don’t look suspicious.

Speaking of silent but deadly, Levitt doubts their existence. “Noisy farts can smell just as bad as silent ones,” he says. “That’s another myth that needs to be put to rest.”

Whether silent or musical, all farts are made up of a variety of gases. The majority are made up of nitrogen, oxygen, carbon dioxide, hydrogen and methane — all odorless. As anyone who has been to summer camp knows, methane, even in small amounts, can torch a match. The higher density of methane, the greater the bluish-green flames. The hydrogen in farts can cause a loud popping sound when ignited. Fart smells come in when sulfur gets stirred into the gaseous mix. Hydrogen causes the fart to waft quickly upward.

So, now that we know what’s in them, how do we make them go away? Levitt says that over-the-counter items like Bean-O and Gas-Ex rarely work. Bean-O does, though, have a 24-hour toll-free hot line, (800) 257-8650 (no, it doesn’t spell out F-A-R-T), and has a nifty collection of promotional materials, including a fanny pack and yellow windbreaker (get it?). Antacids work on some people, but Levitt stresses that for the best results, users should take no more than four tablespoons or tablets a day.

For odor, about the only thing that Levitt says works is a fart cushion made of charcoal, called the Tooter Trapper, invented by a man whose co-workers complained of his farts so much that they demanded he be moved out of the office pool into a separate room with a door. The air filter, which you sit on, does a good job of eliminating fart odors but, of course, treats only the results, not the symptoms, of the noxious-smelling gas.

Forget Glade or Airwick, or even matches, to eradicate fart smells. The thing that works best is opening a window. Lighting a match may camouflage the smell but will not dispel it, says Levitt.

And as for masking the sound, Levitt says that depending on the anatomical peculiarities of a person’s anus, sounds can vary when gas is squeezed through such a tight opening. The larger the volume of gas expelled and the greater the pressure exerted, generally the greater the noise, although Levitt says that standing usually tends to minimize the sound over sitting, which can amplify the toot.

Besides food, antibiotics occasionally cause some people to fart more, Levitt says, because the medications can disrupt the natural flora of the colon, thereby making it more difficult to break down certain foods, and thus leading to more flatus.

Americans are probably the most supercilious about farts. Other cultures are less squeamish about them. The British explorer and linguist Sir Richard Francis Burton, who first translated the “Kama Sutra” in 1883, contends in one of his many books that a tribe of Arabian Bedouins created a language of arcane codes and warnings through a series of intricately nuanced farts.

Farting came out of the closet in the United States in the breakthrough 1974 film “Blazing Saddles,” in which Mel Brooks plays Gov. Le Petomane, who serves up baked beans around the campfire one night and hears the results from a bivouac of cowboys. Actually, Brooks’ character was named after Joseph Pujol, known as Le Petroman (which translates to the “Fartiste”), who in 1892 debuted at the Moulin Rouge in Paris with a show that featured Pujol paying a flute, smoking a cigarette, blowing out candles, even singing La Marseillaise from anus air. Pujol extinguished candles from 2 feet away and became famous for his imitations of thunder, cannons and 2 yards of calico fabric being ripped. Pujol opened his own theater (the Pompadour), in which he starred for two decades before dying in 1945.

Levitt says Pujol probably was able to aspirate through his anus, that is, suck air in through his butt, and with that air performed his assortment of tricks. So it really wasn’t Pujol’s farts that amazed his audiences, but merely air that traveled a wee distance, instead of the longer, more arduous trip from mouth to colon to buttocks.

Farts, of course, predate Pujol. The Aristophanes play “The Clouds” contains a reference to farts. In Dante’s “Divine Comedy,” flatulent demons in the eighth ring of Hell make “trumpets of their asses.” Hieronymus Bosch’s “The Garden of Earthly Delights” shows a young woman with red roses shooting out from her derrihre. And in 1776, Benjamin Franklin published a book of bawdy essays called “Fart Proudly.”

Franklin wasn’t the only one who knew that farts are funny. For a host of complex cultural reasons, farts render 10-year-old boys silly, not to mention more than a few grown men who still get amused for some reason by anal gas. It’s a strange thing, though, farts. Take, for example, the expression “old fart.” It’s a term of insult when spoken in the third person, but one of pride when spoken about oneself.

And for those of you who must have an Internet fart connection, there are plenty of places. My personal favorite is farts.com, which offers an audio sampling of scores of farts, and allows viewers to rate the flatulence on several criteria, including verisimilitude, pitch, duration and volume.