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Prevent breast cancer by avoiding light at night
You want to decrease the risk of breast cancer, not just detect it early, since being exposed to light at night, ups the risk, be sure to sleep IN THE DARK
Breast Cancer Awareness month puts breast cancer on your radar. Maybe you booked to have a mammogram, to check all was in order. Maybe you planned to, but life happened.
Let’s face it, by the time you’re picking up a lump in your breast, the ship has sailed.
You’ve GOT a problem.
Preventing breast cancer
In an ideal world, you want to stop breast cancer in it’s tracks, not just detect it early.
So what can you do ?
Well there is the standard advice, eat less and move more.
It is probably good advice. Being overweight and sedentary, definitely increase your risk.
More to breast cancer risk
But, there is something else that contributes to the risk of breast cancer, that few people are talking about.
It is something every women needs to know.
Being exposed to light at night, ups the risk of breast cancer, significantly.
Light at night is a risk
This was reiterated by a study that analysed cancer incidence in the US state of Georgia.
To do this study, the research team, dug through the records in the state cancer register – which is a database of people with cancer, looking for clues.
They specifically probed breast and lung cancer cases, occurring between 2000 and 2007.
The database recorded 34 053 breast cancer cases and 14 458 lung cancers …..
The Georgia cancer register
Not much was known about each victim, but the set up of the database, did give the researchers details of the cancer type and the county, in which the person was living, at the time of diagnosis.
Armed with this information, the team tracked how much light there was in the person’s neighbourhood at night, in the year’s prior to their diagnosis, using satellite images.
They worked it out for each year, going back as far as 1992.
Lighting up the sky at night
Neighbourhoods were classified as low, medium or high.
The calculation gave them a picture of how much light each person had experienced outside their home, at night. They obviously were clueless as to how much light the person had experienced inside their home each night, and could not be sure, how long the person lived at that particular address.
But they figured……….. there would be some correlation, because the more light there is outside, the more light gets in.
The cancer maps
Next they created a map of where the breast cancer and lung cancer cases had occurred.
In the case of lung cancer – there was no pattern.
This makes sense, the risk of lung cancer is strongly correlated with whether you smoke or not. It might also be related to air pollution, but air pollution is not directly related to “light” pollution.
When it came to the risk of breast cancer, the story was very very different.
More light, more breast cancer
In the places with HIGH light at night, there were a lot more cases of breast cancer.
Here are the maps they put together.
Breast cancer by county and light at night exposure in Georgia. Copyright 2013 Bauer et al
On the left, the cases of breast cancer in each county are reported. The darker the colour, the more women living in that county had a diagnosis of breast cancer. On the right, is the light exposure pattern for Georgia in 2007. The bright red spots are where light pollution is at its highest and the dark blue areas, where the light pollution is lowest.
There is definitely a pattern.
But it’s no definitive
The data is NOT perfect.
There are a lot of things the team could not factor in, whether the person was, thin or fat, or whether they were couch potatoes etc.
But…………….it does suggest light is an issue.
Especially viewed with other evidence….
Other evidence light at night matters
There is a growing body of evidence linking light at night with the risk of breast cancer
- The same pattern has been seen in other ecological studies done in California, Hong Kong, Korea, Israel.
- Exposure to light at night, increases the incidence of breast cancer in lab animals.
- Women who work night shift, and are thus exposed to high levels of light at night, are at increased risk of breast cancer
- Blind women , who are not able to sense light at night, are at lower risk of breast cancer.
- Breast cancer is spreading to the developing world, along with western diets and ELECTRIFICATION.
Plus, the idea that breast cancer could be related to light exposure is biologically plausible.
Light at night suppresses melatonin
Melatonin is usually associated with sleep. Think of the hormone melatonin as your night valet. He is responsible for getting you ready for bed – he draws the curtains, turns down the covers and puts a mint on your pillow.
But his duties extend beyond putting you to bed, he serves you ALL NIGHT.
And night time is when your body cleans up………………….. mistakes and mishaps that have happened during the day. And mistakes happen.
Watch you light hygiene
Fortunately, limiting exposure to light at night is something you can do something about.
Make sure you are sleeping IN THE DARK.
Block out the light from the neighbourhood by closing doors and hanging thick curtains or blinds. If that is not an option, slap on an eye mask.
Help melatonin and the other night workers in your body, do their job.
Further reading
Clock watching uncovers one reason why beta cells fail in diabetes
Pancreatic clocks tick better when spend time in the dark. Unfortunately, being IN THE DARK, doesn’t always happen, light at night is commonplace.
Not sleeping in the dark, might be making you FAT
You’re a regular Jo, most nights, you climb into bed and ……………you’re off to dreamland. Sleep issues don’t explain your weight problems. Not so fast…….
Avoid breast cancer by feeding your beasties
Gut bacteria use their chemical wizardry to bump up your body’s estrogen levels, and too much estrogen often drives breast cancer.