TORONTO -- They're often the butt of ribald jokes or the subject of such motherly advice as 'Don't sit on cold cement, you'll get piles."

But for anyone who suffers from hemorrhoids, there is nothing funny about having the condition or the embarrassment it can cause.

Hemorrhoids -- derived from the Greek word haimorrhois, meaning "liable to discharge blood" -- are clumps of tissue containing veins and tiny arteries that have become swollen and inflamed.

They can be either internal, located inside the rectum, or external, developing under the skin around the anus and often large enough to hang down.

"Internal hemorrhoids are not usually painful," says Dr. Iain Cleator, whose Vancouver clinic specializes in their treatment. "But they're often associated with other conditions, and the commonest condition is a thing called a fissure."

A fissure is a tear in the lining of the anal canal, which can be further opened up by the passage of stool during a bowel movement. "And that becomes painful and bleeds and itches," Cleator explains.

"When hemorrhoids themselves are painful, it's when they get blood clots in them, which is relatively rare."

Hemorrhoids may result from straining during bowel movements or from increased pressure on blood vessels, during pregnancy for instance. There is often a genetic component, as the occurrence of hemorrhoids tends to run in families.

A severe case can have profound effects on a person's day-to-day life, Cleator suggests.

"First of all, there's something sticking out all the time. Secondly it rubs, thirdly you can be bleeding into your underwear or through your trousers or whatever, and that can be very distressing. And, of course, you can also get leakage of stool and mucus."

Katherine, who's in her mid-40s, has been suffering from both internal and external hemorrhoids for more than a decade.

Her first inkling there was something wrong came when she noticed she was experiencing pain "down there." Her doctor told her she had hemorrhoids and referred her to a specialist.

But it wasn't until she discovered "bright red" blood during a prolonged bowel movement that she realized just what the presence of these small grape-like clusters could mean.

"I was freaked out. I totally freaked out. I didn't know what the heck it was," recalls Katherine, who asked that her full name not be used.

A friend drove her to the hospital emergency department, where doctors said her hemorrhoids had become thrombosed, or full of blood, and had burst. Since then, she always wears a panty liner or pad, just in case.

Katherine believes her hemorrhoids are the result of stress and are exacerbated by another stress-related condition called irritable bowel syndrome, which is often marked by alternating episodes of constipation and diarrhea.

"When I do have a really bad episode, where I'm on the toilet constantly and I'm there for longer periods of time, when all the external ones do come out, then it's hard to sit, walk, lie -- anything," she says. "Everything is difficult, that's how painful they are.

"So if you can imagine, it's like little grapes that are sticking out all on top of each other. Yucky."

Katherine's case is hardly rare. Between 60 and 70 per cent of Canadians will develop hemorrhoids at some point in their lifetime, and at least half of people over age 50 are affected by the cushion-like growths.

"It's very, very common," says Cleator. "It's mostly due to our diet in North America, which is processed food, which has had the soluble fibre removed from it and salt and sugar substituted."

In Africa, for example, hemorrhoids are virtually unheard of among people who eat traditional high-fibre foods, he says, although that is beginning to change as more Africans adopt a western diet.

Certain lifestyle factors and activities can contribute to the development of hemorrhoids or make them worse, says Cleator. "Anything that increases intra-abdominal pressure: it could be obesity, it could be pregnancy, it could be weightlifting, it could be riding a bicycle, it could be playing golf."

And men and women are equally affected, Cleator says.

"The common perception is, of course, that women get it more commonly as a result of pregnancy, but in fact that's not true. What happens is they get it earlier as a result of pregnancy. So they get it three or four years younger than they would normally get it."

For some people, hemorrhoids produce only mild discomfort and can be treated with over-the-counter ointments, suppositories or pads that contain such ingredients as witch hazel or hydrocortisone, which can relieve pain and itching.

But if hemorrhoids persistently bleed or are painful, they may need to be removed.

Blood loss "can be huge" in some patients," says Cleator. "We've seen people that have needed to be transfused, just simply from bleeding from their hemorrhoids or fissures.

"Usually the large bleeds are more from the fissures than the hemorrhoids, but it can be from either. But you can lose quite a lot of blood from hemorrhoids on their own."

Cleator specializes in what's called rubber band ligation, in which tiny rubber bands are tightened around the base of an internal hemorrhoid to cut off its circulation. Within a week or so, the hemorrhoid withers and falls off.

Some doctors opt for injecting a chemical solution into the hemorrhoid to shrink it, although that procedure is considered less effective than rubber banding; coagulation therapy uses infrared light, laser or heat to shrivel small internal hemorrhoids, but it has a higher rate of recurrence than banding.

Hemorrhoids can also be surgically removed using a variety of techniques, but the procedure carries the highest rate of complications, including urinary tract infections and temporary difficulty emptying the bladder.

Eric, a patient in his early 40s who asked that his real name not be used, had been plagued by hemorrhoids for years, but was too embarrassed to see a doctor and suffered in silence.

"At the beginning of this year, it was getting worse ... There was a lot of blood, for a couple of days, so I thought it was about time to see a doctor."

Eric was referred to Cleator, who performed rubber band ligation to get rid of his internal hemorrhoids, one at a time in appointments about a month apart. He is scheduled to have the third and final one tied off this week.

"I didn't feel anything," he says. "The whole treatment took about 10 or 20 seconds. It was surprising."

For Katherine, dealing with the condition hasn't been so simple. She is among the roughly eight per cent of people whose hemorrhoids recur, despite treatment.

"I'm constantly getting them," she says. "We band them, I get rid of them, and I then get them again."

One thing Cleator stresses is that patients need to consume a high-fibre diet to prevent hemorrhoids developing in the first place -- and especially to stop them recurring. Women should be ingesting 25 grams of soluble fibre per day, while men need 35 grams. North Americans average only about 10 to 12 grams daily, he says.

"So it's very important to increase the amount of fibre in your diet."

Here are some home remedies compiled by the Mayo Clinic for relieving mild pain, swelling and inflammation of hemorrhoids:

-- Apply an over-the-counter hemorrhoid cream or suppository containing hydrocortisone, or use pads containing witch hazel or a numbing agent.

-- Soak regularly in a warm bath or sitz bath. Soak anal area 10 to 15 minutes two to three times a day.

-- Keep the area clean. Bathe (preferably) or shower daily with warm water to gently cleanse the skin around the anus. Soap isn't necessary and may aggravate the problem. Gently dry the area with a hair dryer after bathing.

-- Don't use dry toilet paper. To help keep the area clean after a bowel movement, use moist towelettes or wet toilet paper that don't contain perfume or alcohol.

-- Apply ice packs or cold compresses to the area to relieve swelling.

--T ake an oral pain reliever, such as acetaminophen or ibuprofen, temporarily to help relieve discomfort.

With these treatments, hemorrhoid symptoms often go away in a few days. See a doctor if there is no relief within a few days, or sooner if there is severe pain or bleeding.