Avoid breast cancer. Sleep in the dark...

[lindisfarne]

http://news.independent.co.uk/uk/health_medical/article1090208.ece

Avoid breast cancer. Sleep in the dark...
... and you could reduce the chances of getting breast cancer. Dramatic new research shows the risks to women of artificial lights at night, in or out of bed
By Geoffrey Lean, Environment Editor
Published: 18 June 2006
Sleeping with the light on or staying up late could be a cause of breast cancer, authoritative new research suggests.

The research - which is being hailed as a "watershed", providing "the first proof" of a link between artificial light at night and cancer - confirms a mass of the studies suggesting that modern life causes the disease by interfering with natural sleep cycles.

Carried out by the blue-chip National Cancer Institute and National Institute of Environmental Health Sciences in the United States, it offers a solution to the mystery of rising levels of breast cancer in rich countries, which are five times as high as in the developing world. One in 10 women will develop the disease.

<snip>
Studies show that light at night interferes with one of the body's greatest natural defences against cancer - melatonin, dubbed "the hormone of darkness". The hormone - which is secreted by the pineal gland at night, and particularly in the early hours of the morning - both impedes the growth of cancers and boosts the immune system.

Light, however, stops its production, making the body think it is daytime.
<snip>

[BrklynLiberal]

1. That is really very interesting, particularly considering how much

artificial light we live with nowadays.

[Berry Cool]

2. What the ?*&!$#@!?&!?

This is the craziest theory I ever heard of in my life.

How many women sleep with the LIGHTS ON??

What? Now they're supposed to blame themselves because they stay up too late?!?

[DELUSIONAL]

3. oh poop -- more garbage

Increased chemicals -- etc etc etc etc

Have babies -- nurse them -- don't -- blah blah blah

Wear a bra -- or don't wear a bra.

Genes -- it's genes -- blah blah

[Warpy]

4. Yeah, everything but the chemical soup we're living in

with pesticides, food adulterants, air pollution, water pollution, and all sorts of other gross crap.

Until they start looking more closely at this, the whole business will continue to get blamed on stupid things like night lights and shift work.

[lindisfarne]

5. Read the article! Lights at night *contribute* to breast cancer risk but

don't account for all of it.

It's rather silly to reject well-designed studies simply because they don't agree with your world view.

"Experts believe that half of the cancers are likely to be accounted for by family history, smoking, drinking alcohol, diet, medicines, and such reproductive factors as childlessness and having children late. But evidence has been building up that electric light during the hours of darkness may be responsible for much of the rest.

Repeated studies have shown that night-shift workers - such as nurses or air stewardesses - are up to 60 per cent more likely to get the disease. Another found that women who stayed up late two or three times a week were similarly susceptible. Conversely totally blind women are half as likely to succumb to it."

[varkam]

9. Huh?

It's rather silly to reject well-designed studies simply because they don't agree with your world view.

You're not a regular around the health forums, I take it.

:)

[Warpy]

10. Don't ASSume I haven't read something

because it doesn't conform to YOUR world view.

This stuff has been around for many years. It's not the first study to point out that shift workers and night owls have an increased risk of breast cancer. This article is just more reinventing the wheel, regurgitating a study that was done over a decade ago. There is nothing new here and much is absent.

The fact is that we're in the infancy of understanding our own chemistry and environmental effects upon it.

Another fact is that many industries are considered sacrosanct and the possibility of their contribution to this disease isn't being studied simply because funding is mysteriously absent.

I'm sure in another decade, this study will once again be offered up to us again as something new and different while other factors are duly neglected.

[lindisfarne]

12. Actually, the study I cited is new. Other studies have been done in

the past, and observations that night shift workers seemed to have a higher incidence of certain cancers were a partial motivation for these kinds of studies.

Science and medical research doesn't happen overnight: it happens by an accumulation of evidence, pointing toward a general conclusion, but also one study refining a previous one in some manner (or perhaps, simply replicating - which is an important step as well). As initially we may not understand all the relevant factors, the conclusions evolve. A body of well-designed studies carried out over a number of years is the goal of science. There's very little that we "know" today that we won't "know" and "understand" much better in 20 years, or 50 years.

[Brigid]

6. Oh, come on!

Who really wrote this -- The Onion? :eyes:

[lindisfarne]

7. This isn't the first study to contribute evidence; go to pubmed.com

and search: breast cancer light melatonin

=====================================================
Eur J Cancer. 2005 Sep;41(13):2023-32. Related Articles, Links
Night work and breast cancer risk: a systematic review and meta-analysis.

Megdal SP, Kroenke CH, Laden F, Pukkala E, Schernhammer ES.

Milken Community High School, Los Angeles, CA, USA.

The association between occupations that involve night shift work (a surrogate for exposure to light at night with subsequent melatonin suppression) and breast cancer risk is uncertain. We therefore conducted a systematic review and meta-analysis of observational studies to assess the effects of night work on breast cancer risk. Data sources were MEDLINE from January 1960 to January 2005, experts in the field, bibliographies, and abstracts. Search terms included night work terms, flight personnel terms, cancer terms, and risk terms. Independent data extraction by two authors using standardised forms was performed. The method of DerSimonian and Laird was used to derive combined estimates and Egger's; and Begg and Mazumdar's tests for publication bias were conducted. Based on 13 studies, including seven studies of airline cabin crew and six studies of other night shift workers, the aggregate estimate for all studies combined was 1.48 (95% CI, 1.36-1.61), with a similar significant elevation of breast cancer risk among female airline cabin crew (standardised incidence ratio (SIR), 1.44; 95% CI, 1.26-1.65), and female night workers (relative risk (RR), 1.51; 95% CI, 1.36-1.68) separately. We found some evidence suggesting confounding due to incomplete adjustment for breast cancer risk factors, with smaller effects in the studies that more completely adjusted for reproductive history and other confounding factors. Egger's and Begg and Mazumdar's tests for publication bias showed no significant asymmetry (P>0.05). Studies on night shift work and breast cancer risk collectively show an increased breast cancer risk among women. Publication bias is unlikely to have influenced the results.
======================

Epidemiology. 2006 Jan;17(1):108-11. Related Articles, Links

Night work and risk of breast cancer.

Schernhammer ES, Kroenke CH, Laden F, Hankinson SE.

Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA. [e-mail]

BACKGROUND: Melatonin shows potential oncostatic activity and is acutely suppressed by light exposure. Some evidence suggests an association between night work and breast cancer risk, possibly through the melatonin pathway. METHODS: In a cohort of premenopausal nurses, we prospectively studied the relation between rotating night shift work and breast cancer risk. Total number of months during which the nurses worked rotating night shifts was first assessed at baseline in 1989 and periodically updated thereafter. We used Cox proportional hazards models to calculate relative risks (RRs) and 95% confidence intervals (CIs). RESULTS: Among 115,022 women without cancer at baseline, 1,352 developed invasive breast cancer during 12 years of follow up. Women who reported more than 20 years of rotating night shift work experienced an elevated relative risk of breast cancer compared with women who did not report any rotating night shift work (multivariate RR = 1.79; 95% CI = 1.06-3.01). There was no increase in risk associated with fewer years of rotating night work. CONCLUSION: Our results suggest a modestly elevated risk of breast cancer after longer periods of rotating night work. Additional studies are warranted to rule out small sample size or uncontrolled sources for confounding as alternative explanations.
===================

Circadian disruption, shift work and the risk of cancer: a summary of the evidence and studies in Seattle.
Cancer Causes Control. 2006 May;17(4):539-45.
Davis S, Mirick DK.

Program in Epidemiology, Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, and Department of Epidemiology, School of Public Health and Community Medicine, University of Washington, Seattle, WA 98109-1024, USA. [e-mail]

There is increasing interest in the possibility that disruption of normal circadian rhythm may increase the risk of developing cancer. Persons who engage in nightshift work may exhibit altered nighttime melatonin levels and reproductive hormone profiles that could increase the risk of hormone-related diseases, including breast cancer. Epidemiologic studies are now beginning to emerge suggesting that women who work at night, and who experience sleep deprivation, circadian disruption, and exposure to light-at-night are at an increased risk of breast cancer, and possibly colorectal cancer as well. Several studies have been conducted in Seattle recently to investigate the effects of factors that can disrupt circadian rhythm and alter normal nocturnal production of melatonin and reproductive hormones of relevance to breast cancer etiology. Studies completed to date have found: (1) an increased risk of breast cancer associated with indicators of exposure to light-at-night and night shift work; and (2) decreased nocturnal urinary levels of 6-sulphatoxymelatonin associated with exposure to 60-Hz magnetic fields in the bedroom the same night, and a number of other factors including hours of daylight, season, alcohol consumption and body mass index. Recently completed is an experimental crossover study designed to investigate whether exposure to a 60-Hz magnetic field under controlled conditions in the home sleeping environment is associated with a decrease in nocturnal urinary concentration of 6-sulphatoxymelatonin, and an increase in the urinary concentration of luteinizing hormone, follicle stimulating hormone, and estradiol in a sample of healthy women of reproductive age. Presently underway is a study to determine whether working at night is associated with decreased levels of urinary 6-sulphatoxymelatonin, and increased urinary concentrations of the reproductive hormones listed above in a sample of healthy women of reproductive age, and to elucidate characteristics of sleep among night shift workers that are related to the hormone patterns identified. A proposal is under review to extend these studies to a sample of healthy men to investigate whether working at night is associated with decreased levels of urinary 6-sulphatoxymelatonin, and increased concentrations of urinary cortisol and cortisone, urinary levels of a number of androgen metabolites, and serum concentrations of a number of reproductive hormones. Secondarily, the proposed study will elucidate characteristics of sleep among night shift workers that are related to the hormone patterns identified, as well as investigate whether polymorphisms of the genes thought to regulate the human circadian clock are associated with the ability to adapt to night shift work. It is anticipated that collectively these studies will enhance our understanding of the role of circadian disruption in the etiology of cancer.

[Rageneau]

8. If it's a melotonin deficiency, can't women just eat more melons?

[lindisfarne]

11. They haven't looked at melons, but melatonin has been looked at to a small

degree. Larger studies need to take place.
----------------------------------------------------
Melatonin has been shown to slow or stop the growth of several cancer cell lines when studied in the lab. Whether or not this same effect occurs in the body is unknown, however.

Several studies have looked at the effects of giving melatonin to treat cancer. Melatonin has been used alone and combined with chemotherapy, radiation therapy, hormone therapy (such as tamoxifen), or immunotherapy (such as interleukin-2) in a number of studies involving different types of cancer. Some of the studies have suggested that melatonin may extend survival and improve quality of life for patients with certain types of untreatable cancers such as advanced lung cancer and melanoma. Some studies reported that a small number of cancers went into total or partial remission, while others indicated that melatonin caused little or no response in tumors.

Most of the studies reporting positive results were small and conducted by the same group of Italian researchers. Before the results are widely accepted, they will need to be confirmed in larger studies done at other centers.
http://www.cancer.org/docroot/ETO/content/ETO_5_3X_Melatonin.asp?sitearea=ETO

[HysteryDiagnosis]

13. Break out the blacklights... must be them hippies knew more than

they thought they did.

[HysteryDiagnosis]

14. Breast cancer must be down in Baghdad.... mebbe we should call

in an airstrike on a power station of two.