Thursday, July 15, 2010

Coffee may help prevent cancer

The ups and downs of the rights and wrongs of coffee consumption again. The fact that each study below found benefits in different parts of the body strongly suggests that we are just looking at data dredging

Several new studies suggest coffee helps prevent breast, prostate, head and neck cancers. While too much coffee can cause health problems, such as ulcers, the new research suggests generous amounts of it are most strongly linked to lower cancer rates -- between two and five cups daily, or even more, depending on the study and cancer type.

In one analysis, researchers pooled data on regular coffee drinkers and nondrinkers from nine studies collected by the International Head and Neck Cancer Epidemiology consortium.

People who drank about four or more cups a day had a 39 percent decreased risk of oral cavity and pharynx cancers combined, the investigators found. Data on decaffeinated coffee was too sparse for detailed analysis, they added, but indicated no increased risk. Tea intake wasn't associated with head and neck cancer risk.

"What makes our results so unique is that we had a very large sample size. we had more statistical power to detect associations between cancer and coffee," said said lead researcher Mia Hashibe of the University of Utah.

The research is published in the advance online issue of the journal Cancer Epidemiology, Biomarkers & Prevention, published by the American Association for Cancer Research.

In another study, presented at the association's Frontiers in Cancer Prevention Research Conference last December, Harvard University researchers presented data showing that men who drank the most coffee had an up to 60 percent decreased risk of lethal and advanced prostate cancers.

Results of a third study published in the January issue of the same journal showed a decreased risk of gliomas, or brain tumors, associated with coffee. This link was found among those who drank five or more cups of coffee or tea a day, according the researchers from Imperial College, London.

And yet a fourth study, in the April 2008 issue of Cancer Epidemiology, Biomarkers & Prevention, found that at least two or three cups of coffee a day can either reduce the risk of breast cancer or delay its onset.

This effect is related to estrogens, female sex hormones, said the scientists, from Lund and Malmo universities in Sweden. Certain metabolic products of these hormones are known to be carcinogen, and various components of coffee can alter the metabolism so that a woman acquires a better configuration of various estrogens, investigators said. Caffeine also hampers cancer cell growth.

In the study, researcher Helena Jernstrom and colleagues studied the coffee-drinking habits of women including nearly 460 breast cancer patients at Lund. Coffee's effect, the scientists said, varied depending on which version women have of a gene called CYP1A2, which produces an enzyme that breaks down estrogen and coffee. Half of the women had a variant called A/A, while the others had either A/C or C/C.

"Those women who had one of the C variants, and who had drunk at least three cups of coffee a day, developed breast cancer considerably more seldom than women with the A/A variant with the same coffee consumption. Their cancer risk was only two thirds of that of the other women," Jernstrom said.


Cell phones don’t cause cancer

This is such an old chestnut that I am disinclined to write on it again but the author below has some good points

Could your cell phone be killing you? A lot of people seem to think so. Some activists say that talking on your phone for 30 minutes a day over several years can cause brain tumors. They say governments need to address the problem with regulations. The alternative? “[D]o nothing and wait for the body count,” according to the University of Albany’s David Carpenter.

Regulations are starting to pass. San Francisco just passed a law requiring cell phone retailers to disclose how much radiation their products emit. The city already has a warning label regulation. Maine passed its own warning label mandate last year.

Now Rep. Dennis Kucinich (D-OH) is introducing federal labeling legislation, so that “cell phone users can decide for themselves the level of risk that they will accept.”

Fortunately, when it comes to cell phones and cancer, that risk is zero. It is physically impossible for cell phones to cause cancer. Literally. Most phones only emit about one watt of energy. The legal limit is 1.6 watts. This is not nearly enough to cause the tissue damages that cause many kinds of cancer.

How little energy is one watt? The human body generates about a hundred times that much energy during normal, everyday activity. During exercise, our bodies can pump out more than 1,100 watts of energy – enough to power a whole row of light bulbs. Adding a single watt to that baseline does nothing to contribute to the DNA damage that can lead to tumor growth.

So if scare-mongerers are right that one-watt cell phones can cause brain tumors, they should be at least a thousand times more worried about working out. But they aren’t. Suspicious.

There’s more. Not only are cell phones too weak to cause tissue damage, they don’t even operate at the right frequency to do so. Some frequencies are dangerous to living tissue. Others aren’t. The sun’s visible light is harmless to humans. But its higher-energy UV rays have caused countless cases of skin cancer among the sun-bathing set.

The physicist Bernard Leikind found that cell phone photons are so weak, they fall short of DNA-damaging energy levels by about a factor of 500,000.

So you might have something to worry about if you strapped half a million cell phones to your body. But it wouldn’t be cancer – it would be getting crushed to death. So talk on your phone all you want. Unless you’re driving while you’re gabbing, you are safe.

The cell phone cancer scare probably says more about the people promoting it than anything else. Activists promoting the scare only ever mention brain tumors. And brain tumors are frightening. But you hold your cell phone in your hand. You hold it next to your ear and your jaw. Why no mention of those cancers?

They should be just as worried about skin and bone cancers in the hand. They should also be worried about the ears and the jaws. Not to mention the scalp and skull that take in every bit as much cell phone radiation as the brain. This strangely selective choice of scare-mongering is reason to be suspicious of the phone-cancer connection. Some people just like to be scared. And other people can get massive amounts of funding by catering to those people.

So don’t buy into the hype. David Carpenter and Dennis Kucinich can live in bed-wetting fear of their phones if they like. But you don’t have to.


No comments: