"It ain't what we don't know that hurts us . . ."

". . . it's what we know that ain't so." Mark Twain's famous saying should be carved over the doorways of most media outlets. TimesOnline does a bit to refute some common mistaken beliefs about health and medicine:

HAVING SEX CAN CAUSE A HEART ATTACK IN MEN

How wrong is this? Fairly. The risk is hugely exaggerated by the familiar portrayals of men in books, films and dramas gasping their last in flagrante.

What are the facts? Research shows that the chances of a 50-year-old non-smoking male suffering a heart attack is about one in a million in any hour. Having sex increases these odds to two in a million, but doubling a barely existent risk means that risk is still negligible.

Any related myths? That sex is a form of exercise. In fact, it equates only to climbing two flights of stairs.

[. . .]

HEADACHES ALONE CAN BE A SIGN OF A BRAIN TUMOUR

How wrong is this? Totally.

What are the facts? The stats alone may be ease your headache. After all, your GP sees this symptom daily, but encounters a brain tumour only a few times in his entire career. Nasties of this sort almost always produce other symptoms — fits, personality change or unsteadiness.

Any related myths? That a scan is a good idea. The chances of turning up an irrelevant but worrying abnormality are fairly high.

YOU SHOULDN'T MIX ANTIBIOTICS AND ALCOHOL

How wrong is this? Totally, with the exception of the antibiotic metronidazole.

What are the facts? Any interaction of alcohol with virtually all antibiotics is nonexistent, or so small as to be irrelevant. Metronidazole, an antibiotic used for a variety of infections, is the exception to this rule. When mixed with even small amounts of booze, it causes vomiting.

Any related myths? That you should always finish your course of antibiotics. It usually makes little difference.

Update: The usual suspects weigh in on the Fark thread (the usual warnings apply about NSFW language and images at that link).