Cracking Knuckles

Myth: Cracking your knuckles will cause arthritis.

Short answer: No, cracking your knuckles will NOT cause arthritis.

But it does correlate to a few other hand problems. In a paper looking at 300 individuals aged 45 and over, 76 of them admitted to being habitual knuckle crackers ^[1]. There was no predominant increase in arthritis in either group. However the cracking knuckles group was found to have a higher rate of hand swelling and lower grip strength. A correlation to be sure, and not necessarily an effect.

Though this is the results from one rather limited study. It seems as popular as knuckle cracking is, looking into the subject empirically just isn't.

The few articles on the subject conclude there is no cause and effect where knuckle cracking leads to arthritis. Most of them also conclude that you shouldn't do it anyway. If nothing else, it potentially annoys those around you.


References:

• [1] Castellanos J. Axelrod D. "Effect of habitual knuckle cracking on hand function". Annals of the rheumatic diseases. 49(5):308-9. 1990. ARD Online.

Lazy Video Post

Link to videos

Will be back Friday with our regular hard-hitting posts.

On Old Wives' Tales

Old Wife

As requested by reader Andrew, I did try to look up the origin of the term "Old Wives' Tale". The best I could do was a reference to The American Heritage Dictionary of Idioms.

A superstition, as in Toads cause warts? That's an old wives' tale. This expression was already known in ancient Greece, and a version in English was recorded in 1387. Despite invoking bigoted stereotypes of women and old people, it survives.

So it seems too old to trace back to any one spot, it was indeed quite old.

Also, if it seemed like my beard article was a bit dated, it was. (I found a debunking to that myth dating 1928!) What's important here is that a reader asked for the info, and I went out to get it and make it easy to interpret, to the best of my ability. So by all means, ask for articles on particular subjects and I'll do what I can to write on them and maybe provide you with some new info. Even if the myths are bunk and/or old. As for gum in the digestive system, it goes right through just as fast as any other food, even though it doesn't get broken down. (http://www.snopes.com/oldwives/chewgum.asp)

In the future, as suggested by one of my readers, I may start commenting on political goings-on. Though it's not really my area of knowledge, I can try. What does everyone think of that? Do you want to start seeing some politically themed articles?

Shaving and Hair Growth

An awesome beard

Reader Lucas and I really want to know if shaving will increase beard growth. The quick answer is: No, shaving will not increase hair growth, beard or otherwise.

The Myth: Hair grows back darker or thicker after it has been shaved.

Though I couldn't find when the myth dates to, the earliest paper on the subject I found was from 1928. There are a bunch of F.A.Q.s on the subject and several published papers, the most useful I found, "The Effects of Shaving on Hair Growth" by Linda Edsell ^[1].

The hair shaft (this is the hair that is cut off when shaving) is a dead, cornified structure that extends from the follicle above the surface of the skin: only the follicle is alive. To make any difference in hair growth, the follicle itself must be disturbed. Shaving or cutting the dead structure (hair) will not have any effect on the follicle itself.

The first study on hair growth, "Hair growth and shaving" by Trotter, ^[2] used three girls as subjects. They shaved twice per week for eight months. It was concluded that:

At the end of this time, microscopic examination revealed that there was absolutely no increase in the diameter or color of the hairs before or after the shaving period.

The findings finished with explanations of why it might be perceived that shaving increases hair growth. The first being growth rates. For example, if a persons beard grows a quarter inch per week and was just shaved, a week later their beard growth will appear very impressive. But if they already have a 2 inch beard, a quarter inch of growth that week is only a 12.5% increase. Significantly less noticeable. Another reason is that freshly shaved hair has sharper ends and can be held straighter by the follicle, which leads to a harsher feeling beard following a shave.

I hope that answered your question. Here are some more shaving/beard resources:

• http://beardcommunity.com/faq.php#2
• http://www.hairfacts.com/medpubs/shavemed.html
• http://www.snopes.com/oldwives/hairgrow.asp
• http://www.beards.org/
• http://www.worldbeardchampionships.com/

References:

1. Edsell, Linda C. "The Effects of Shaving on Hair Growth". International Hair Route Magazine.
2. Trotter, M. "Hair growth and shaving". Anatomical Record. December 1928, 37:373-379

More on Sylvia Browne

Some more information on Sylvia Browne from Friday's post. A post in Randi's newsletter tipped me off to another blog that also examined Sylvia Browne. The author looked into some of the claims she made during her radio interview (apart from the miners) and did some research on how extraordinary the claims might be. He went into some good depth, something that makes me wish I had thought of it first. From http://www.livejournal.com/users/baron_army/109284.html:

New health treatments include an insulin replacement for diabetes, a vaccine for stomach-related cancers, a breakthrough in MS involving the hypothalamus gland, and a vaccine that blocks the need for nicotine.

• A very quick Google search on "insulin replacement" found this.

• A search for "vaccine for stomach-related cancers" found this:
  Korean breakthrough on stomach cancer (08/12)[...]

And it goes on. All of her specific medical predictions are stories that broke well before her interview, sometimes by years! It's worth a read just to get some familiarity with some general psychic predictions. Either so vague it doesn't matter, or specific because they pull from known fact. Whatever the case, they aren't supernatural.

-=-=-

Also from Randi this week: "Atheism is a religion like not collecting stamps is a hobby."

Sylvia Browne in deep

You might have heard of Sylvia Browne, a psychic medium, who has had been on Randi's commentary newsletter more than once. She even accepted Randi's paranormal challenge, but that was 222 weeks ago. Yet to appear.

January 3, she was on a radio show (Coast to Coast) during the mining disaster in West Virginia. Early in the rescue operation, they reported that at least twelve of the thirteen trapped miners were known to be alive. This was, unfortunately, a wrong announcement, and that really twelve of the thirteen had died. For some reason, his horrible news stayed quite for three to four hours. During the radio show, Browne was heard saying that she psychically knew the miners were alright. But this was after the rescuers had found that truly, the majority of the miners had perished. After the bad news finally broke, she quickly reversed her story. Source: Fox.

As an aside, Sylvia Browne's website (I loath putting a link to it here) has a note to the Skeptic Society posted front and center. The thrust of the note is that she doesn't find it important to prove that she really is psychic. At least, not empirically.

"Somehow, in my willingness to enter into public discussions with you, I’ve mistakenly led you to believe that I have a stake of some sort in your approval, when nothing could be further from the truth."

Which is more outrageous: 1) Sylvia Browne really is psychic, which throws half of modern science to the wind, and she doesn't find it important enough to prove this; or perhaps 2) she is yet another fraud and gets away with it by preying on those who want while refusing to give rational explanations? Her second paragraph is a wash and I'll explain why in respect to her third paragraph...

"...please, please do what I would have done with it and donate it to a worthy, legitimate charity."

She is speaking about her reneged application for the JREF Million Dollar Prize. Being that Browne is relatively high profile in the psychic world, Randi would no doubt fast-track the testing procedure. Her acceptance (mov) of the test was on Larry King Live, after all. So with little effort she could go win the prize money herself. She claims she has no interest, and that Randi should donate the cash. Winning the money would do so much for her. Firstly, it would shut Randi up for a good while and that would make many, many people happy; they would clearly donate lots of money to whichever charity Browne wanted. She would prove psychic ability, she would change the face of modern science, and she could look awesome by donating the money herself. But, none of these things will ever happen. If pyschic powers do exists, show the world! Prove it using natural science! Sylvia Browne won't take the test of course, because I dare say, she knows she can not prove her psychic powers, precisely because she has none.

PS: Wednesday's post wasn't up for very long, because of my lateness. So be sure to check it out if you haven't. Skeptics Society Letter.

Skeptics Society Letter

Today I received a mailing from The Skeptics Society about fighting Intelligent Design in the public classroom. Firstly, it's cool to get a mailing from a group I actually want to get mailings from. Here are some interesting statistics it listed:

2005 Harris Poll
38% - Yes, I think human beings developed from earlier species.
54% - No, I do not think human beings developed from earlier species.
8% - Not sure.

2005 Pew Research Center Poll
36% - Replace evolution with creationism in biology classrooms.
64% - Open to the idea of teaching both creationism and evolution in public schools.

The Pew poll seemed odd to me, so I tried to find the source. The closest I could match was this page from people-press.org. Which shows that people were asked two different questions, not an either/or. I think I'll email Michael Shermer and ask him to clarify.

To add even more recommended reading this week... check out the Skeptic.com Reading Room.

"A comprehensive, free resource of articles relating to science and skepticism, as well as a community-building hub for skeptics everywhere."

As an aside, Blogger was giving me some problems when I tried to post last night. Instead of complaining, starting next week, I'm going to try and get the post up the morning of, instead of the night of. So Monday morning bright and early instead of Monday night.

What is your dangerous idea?

A great article was recently published at Edge.org. A website that asks questions. For example, "“What is your dangerous idea?"” to which they received 119 replies from scientists. At 75,000 words (about 115 pages) I haven't read even 10% of it. I've read a few of the names I immediately recognize and I'll continue picking people out over the next several days.

Richard Dawkins, for example, has an idea about crime & punishment. His idea is that people that break the law should be treated as if they were broken and in need of fixing, instead of locked away as a lost cause. Interesting but with a frightening pile of ethical questions behind it. This suggests that murderers just need fixing, and not be held responsible for their actions. Which in turn suggests that free-will is rather subjective.

Jared Diamond thinks it's possible that tribal peoples aren't any wiser than the rest of us. This one I find interesting in a skeptical point of view. It's a popular idea that a tribal people are at harmony with their environment, but that may not be the case. Perhaps Diamond will write a book about this.

There are many more interesting ideas in there, like David Pizarro on morality and Andy Clark's zombies.

I'll keep reading them and post about particularly good ones, but if you find one that's ripe for The Lazy Skeptic, post about it in the comments and I'll take a look. Or if you have a particularly dangerous idea, post that in the comments as well!