Live and let dye?!

January 25, 2004 4:13 AM

Live and let dye?!Hair dyeing causes non-Hodgkin's lymphoma, especially in cases of repetitive dyeing over years, especially with darker colors.

This might sound trivial, until the names of some potential victims are mentioned. Jacqueline Kennedy Onasis, Joey Ramone, Louis Malle, Charles Lindbergh, King Hussein of Jordan, Paul Tsongas, Gabriel Garcia Marquez, William Casey, Roger Maris, Mickey Mantle, Steve Reeves, and Mr. T. (Shaddup, foo! I'm in remission!) Not that any of them would ever dye their hair, of course.
posted by insomnia_lj (19 comments total)

Hair dyeing causes...

Slow down there, insomnia. In a survey of 600 people with NHL and 700 controls, they found slightly higher tendency for this already low-incidence cancer in subgroups of those who had dyed longer and darker. It's a thimbleful of data, a long way from "Hair dyeing causes non-Hodgkin's lymphoma."
Don't we see a reversal every month or so on the old "alcohol causes/prevents heart disease" topic?
posted by planetkyoto at 4:47 AM on January 25, 2004

I checked the study, which was done over six years, and they seem to have a 95% confidence interval, which is fairly convincing.

It should be pointed out that those who dyed their hair after 1980 didn't show the correlation between dyeing and cancer. The researchers didn't indicate a need for further studies to prove a correlation between dyeing and Hodgkin's, but they did say that further studies are warranted to show whether the association reflects the change in hair dye formula contents during the past two decades or indicates that recent users are still in their induction/latent periods.
posted by insomnia_lj at 5:33 AM on January 25, 2004

Several men's anti-gray hair dyes contain amounts of lead acetate. That has long impressed me as an astoundingly bad idea.

"...the FDA has studied these lead-containing dyes and has concluded that it is unlikely to be absorbed through the skin."

Right.

"POISON! DANGER! MAY BE FATAL IF SWALLOWED, INHALED OR ABSORBED THROUGH SKIN. SUSPECT CANCER HAZARD. MAY CAUSE CANCER. Risk of cancer depends on level and duration of exposure. CAUSES IRRITATION TO SKIN, EYES AND RESPIRATORY TRACT. NEUROTOXIN. AFFECTS THE GUM TISSUE, CENTRAL NERVOUS SYSTEM, KIDNEYS, BLOOD AND REPRODUCTIVE SYSTEM."
posted by kablam at 6:00 AM on January 25, 2004

[nitpick] Why would it be less "trivial" because it happened to famous people?[/nitpick]
posted by signal at 6:50 AM on January 25, 2004

I'll weigh in with PlanetKyoto here. The article presents retrospective data that using hair dye doubled the risk of developing NHL. That sounds deadly, but if the risk goes from 0.1% to 0.2%, at least those who have died their hair in the past can breathe a sigh of relief.

I think the larger issue is that we never really know about the safety of a new product until years after it's introduced. Take thalidomide for instance... it's an argument against the new-fangled.
posted by mert at 7:10 AM on January 25, 2004

Who is linking off of who? Metafilter from Fark, or Fark from Metafilter?....
posted by tgrundke at 8:15 AM on January 25, 2004

My mother had NHL and she didn't dye her hair.

What about this stuff? The incidence of NHL has nearly doubled over the last 30 years.
posted by jaronson at 9:03 AM on January 25, 2004

I checked the study, which was done over six years, and they seem to have a 95% confidence interval, which is fairly convincing.

Errr, any study should construct some sort of confidence interval around its point-estimates.

I can't get to the study easily, only to the abstract.

But it looks like their 95% CI around the odds ratios includes 1, which could be interpreted as equal risk. I also can't tell whether they're doing some sort of quasi-experiment ending up with 2-sample t-tests or whether they're doing some manner of limited-dependent-variable regression or an event-history regression, either of which could help to control for the zillions of possible confounding factors.
posted by ROU_Xenophobe at 9:40 AM on January 25, 2004

I heard about this back in the 80s (Clairol blueblack was very popular, and people would always say it eventually killed you).

And for years, they've been telling pregnant women not to dye their hair using chemical formulas because it can get to the fetus.
posted by amberglow at 9:46 AM on January 25, 2004

I checked the study, which was done over six years, and they seem to have a 95% confidence interval, which is fairly convincing.

This is convincing with regard to the likelihood that the observed correlation is actually present in the population being generalized to (as opposed to being a product of sampling error). However this is not a reason to assume that the relationship is causal. I haven't dug up the original study but the Yahoo! article doesn't mention what other variables were controlled for. People who dye their hair often with darker colors could differ from people who don't in terms of lifestyle, genetics, etc.

Of course a causal model seems entirely plausible, given the nasty chemicals in hair dye, but the study doesn't appear to allow us to say "hair dye causes lymphoma".

Also, what signal said.

On preview, ROU_Xenophobe: Yes, aside from the specific test used the interesting question is whether other variables were entered into the model and whether or not the hair dye variable would still explain as much of the variance if they were.
posted by boredomjockey at 9:48 AM on January 25, 2004

Marquez isnt dead is he?
posted by Satapher at 9:59 AM on January 25, 2004

I don't know if he's dead, but from here:
Unfortunately, in 1999 García Márquez was diagnosed with lymphatic cancer, and to this day he suffers under a regimen of treatments, often taking him from Cartagena or Mexico City to clinics in Los Angeles...
posted by amberglow at 10:17 AM on January 25, 2004

My grandfather died of Non-Hodgkin's lymphoma, and he didn't even have hair.
posted by mr_crash_davis at 10:56 AM on January 25, 2004

Elvis used Miss Clairol's Blue-Black, and he's fine.
posted by scody at 11:13 AM on January 25, 2004

It should be pointed out that many known/suspected carcinogens have been removed from hair dye since 1980. So to state in the present tense that "Hair dyeing causes non-Hodgkin's lymphoma" may not be strictly accurate.
posted by pmurray63 at 11:26 AM on January 25, 2004

Vanity causes non-Hodgkin's Lymphoma. Grey is okay.
posted by Faze at 4:15 PM on January 25, 2004

*cough* natural selection *cough*
posted by inpHilltr8r at 4:49 PM on January 25, 2004

No, Marquez is not dead.
posted by blissbat at 11:09 PM on January 25, 2004

More to the point I think they should be investigating the effects on your eyesight. I stopped dyeing my hair myslef because I was afraid I was going to go blind from the fumes.

Getting it done professionally does not irritate my eyes or skin at all but it takes way longer. I wonder why?
posted by maggie at 8:59 AM on January 26, 2004