If you know someone with cancer, or you want to prevent getting cancer, you need to read this story about ground breaking research going on right here in New Orleans.

WWL-TV

An image shows how much light is still generated in parts of the United States at night.

Some doctors are finding that some of your night time habits may be putting you at risk.

Two Tulane scientists have put years of research into something that is important to each and everyone of us, something that may contribute to cancer of the breast, prostate, uterus, ovaries, colon and the deadly skin cancer melanoma, something as simple as the importance of getting light in the day and darkness at night.

Remember back in the mid 90s when "The Melatonin Miracle" came out? The book about the natural hormone called melatonin made at night in our brains to help us sleep, had people taking melatonin supplements in hopes of fighting jet lag, insomnia, aging, disease and even enhancing sex lives. Now Tulane doctors David Blask and Steven Hill have made major advancements in the study of melatonin.

"It's a hormone but it's also a nutrient because it's found in virtually all edible plants so there's some scientists who think that melatonin is more than just a hormone. It may in fact be a vitamin," says Tulane Cancer Biologist Dr. David Blask.

So besides being able to control our biological clocks, science is finding that it may be a powerful antioxidant, fighting what destroys our cells as well as keeping cancer cells and tumors from growing.

"It also has and appears to have, from a number of studies throughout the world, an inhibitory, a direct inhibitory effect on a variety of malignancies," says Dr. Steven Hill, a Molecular Endocrinologist at Tulane.  

So at night when it's dark, the small biological clock cells in the brain tell a small gland to send the hormone melatonin through the blood stream and that in a sense turns off the growth of cancer cells and tumors. But there is a big problem in our lives, we have light coming through our eyes and to our brains day and night. Look at these night time satellite pictures in the developed world. It's bright. And when it's bright the gland in the brain stops making melatonin.

"In parts of Israel around cities that have the brightest lighting the highest incidence of breast cancer cluster around those areas," adds Dr. Blask. 

Think about the night lights children use, falling asleep with the TV and computer on, those outside street lights coming through the window and worst of all shift workers who rotate from day to night. Science actually shows that light pollution may cause cancer.

"We think because shift workers are exposed to so much light at night, that that is the factor that is unique, somewhat unique to their profession, that is responsible for the elevated risks of breast, prostate cancer, colorectal cancer, endometrial cancer found in rotating night shift workers," says Dr. Blask.

And there is another reason why we need darkness at night so our bodies can make melatonin. Women need the hormone estrogen made by the ovaries to live, but without enough melatonin at night women may be exposed to more than the normal amount of estrogen nature intended us to have.

"Melatonin working through its own receptor can block or blunt significantly the effects of estrogen and the estrogen receptor so it slows down breast tumor growth in a large percentage of tumors, says Dr. Hill.

Without melatonin the doctors say tumors grow two to seven times faster, and tryptophan that amino acid found in turkey, walnuts, mustard seeds, cherries and Chinese herbs is needed in our diets to help produce melatonin. And melatonin also helps combat all the linoleic acid in junk foods and corn, safflower and cottonseed oils that feed tumors.

"I take melatonin supplements in the evening about an hour before I go to bed, adds Dr. Hill. 

But while Dr. Hill takes 1 milligram a day, Dr. Blask says still more studies are needed before people use supplements.

The doctors say if you need a light at night, use a red bulb in the night light. Red light does not cause the brain to stop making melatonin at night.