Writing — the kind that’s expressive and heartfelt — has long been known to be a kind of self-medication: Jot down your personal thoughts and feelings and you just feel better.

Research backs this up. Studies show writing can improve memory and sleep, boost the immune system, even speed healing. A recent study found that cancer patients who practiced expressive writing just before their surgeries felt better, mentally and physically, than those who did not.

The explosive growth of blogging — there are an estimated 60 million of them in the world, about half in the United States — has some scientists speculating that it’s the feel-good nature of writing that’s driving the blogosphere’s growth.

“You know that (biological) drives are involved (in blogging) because a lot of people do it compulsively,” Alice Flaherty, a Harvard University neuroscientist told Scientific American.

So Flaherty and other researchers are launching studies to parse the neurological reasons of blogging. One possibility: It triggers the release of the brain chemical dopamine, which also happens when people listen to music, look at art or run.

+ GET ME THAT STAT!

A Canadian researcher surveyed more than 2,300 students between the ages of 12 and 18 to assess what types of student were most likely to be socially victimized, such as having harmful rumors spread about them or being excluded by others.

Lindsey Leenaars of the University of Alberta found that females who viewed themselves as attractive had a 35 percent greater chance of being indirectly victimized. Conversely, males who perceived themselves as good-looking were 25 percent less likely to be victimized.

+ BODY OF KNOWLEDGE

It has been estimated that one brow wrinkle is the result of 200,000 frowns.

+ NUMBER CRUNCHER

A 32-ounce Cappuccino Blast from Baskin-Robbins contains 620 calories, 216 from fat. That’s 37 percent of the recommended total fat intake for a 2,000-calorie daily diet.

It also contains 95 milligrams of cholesterol (32 percent); 200 mg of sodium (8 percent); 94 grams of total carbohydrates (31 percent); 85g of sugar and 12g of protein.

+ MEDTRONICA

Diabetes mine

diabetesmine.com

A blog for people with diabetes, created by a diabetic. There are personal stories, advice about food and products, news analysis and recommended books and resources.

+ STORIES FOR THE WAITING ROOM

An 18-year-old girl went to see her doctor, complaining of stomach pains, vomiting and weight loss — 40 pounds over a five-month period.

A scan was ordered, revealing a huge mass of hair blocking her entire stomach. Surgery followed, with a 10-pound hairball or bezoar removed. The mass was 15 inches long and 7 inches wide. The patient recovered and was diagnosed with Rapunzel syndrome, a psychological condition in which one compulsively eats his or her own hair.

+ PHOBIA OF THE WEEK

Eosophobia — fear of dawn

+ OBSERVATION

“The very first requirement in a hospital is that it should do the sick no harm.”

— British nursing pioneer Florence Nightingale (1820-1910)

+ CURTAIN CALLS

In 1996, a 26-year-old burglar successfully broke into a second-floor insurance company in Huntington, N.Y., but was stymied in his attempts to open the company safe. Finally, with morning approaching, the burglar decided to slide the 600-pound safe down a flight of stairs and take the whole thing away in his car.

Putting his back against the front side, the burglar allowed the safe to begin sliding down the stairs. The safe’s weight, however, was too much; the burglar lost his footing and was carried down the stairs with the tumbling safe. The next morning, he was found, crushed to death.

The safe, it turned out, was empty.