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December 2007 vol. 12 no. 12

Nearly all men can stand adversity, but if you want to test a man’s character, give him power.
Abraham Lincoln
16th president of US (1809 - 1865)

Table of Contents:


Lack of Sunlight May Increase Lung Cancer Risk

Lack of sunlight may increase the risk of lung cancer, suggests a study of rates of the disease in over 100 countries, published in the Journal of Epidemiology and Community Health.

Lung cancer kills over a million people every year around the globe.

The researchers looked at the association between latitude, exposure to ultraviolet B (UVB) light, and rates of lung cancer according to age in 111 countries across several continents.

They took account of the amount of cloud cover and aerosol use, both of which absorb UVB light, and cigarette smoking, the primary cause of lung cancer International databases, including those of the World Health Organization, and national health statistics were used.

Smoking was most strongly associated with lung cancer rates, accounting for between 75% and 85% of the cases.

But exposure to sunlight, especially UVB light, the principal source of vitamin D for the body, also seemed to have an impact, the findings showed.

The amount of UVB light increases with proximity to the equator. And the analyses showed that lung cancer rates were highest in those countries furthest away from the equator and lowest in those nearest.

Higher cloud cover and airborne aerosol levels were also associated with higher rates of the disease.

In men, the prevalence of smoking was associated with higher lung cancer rates, while greater exposure to UVB light was associated with lower rates.

Among women, cigarette smoking, total cloud cover, and airborne aerosols were associated with higher rates of lung cancer, while greater exposure to UVB light was associated with lower rates.

The associations for a protective role for UVB light persisted after adjusting for smoking.

The link between cancer and sunlight is chemically plausible, say the authors, because laboratory research has shown that vitamin D can halt tumor growth by promoting the factors responsible for cell death in the body.

Although cigarette smoking is the main cause of lung cancer, greater UVB exposure may reduce the incidence of the disease, they conclude.


Timing of Pills Might Matter

Taking a blood pressure pill at bedtime instead of in the morning might be healthier for some high-risk people. New research suggests that simple switch may normalize patterns of blood pressure in patients at extra risk from the twin epidemics of heart and kidney disease. Why? When it comes to blood pressure, you want to be a dipper. In healthy people, blood pressure dips at night, by 10 to 20 percent. Scientists don’t know why, but suspect the drop gives arteries a little rest.

People with high blood pressure that doesn’t dip at night — the non-dippers — fare worse than other hypertension sufferers, developing more serious heart disease. Moreover, heart and kidney disease fuel each other — and the 26 million Americans with chronic kidney disease seem most prone to non-dipping. In addition to heart problems, they’re at extra risk of their kidney damage worsening to the point of dialysis.

Most blood pressure patients need two or three medications. So Italian researchers performed an easy test: They told 32 non-dippers with kidney disease to switch one of those drugs from a morning to a bedtime dose. In two months, nearly 90 percent of these high-risk patients had turned into dippers. Their nighttime blood pressure dropped an average of 7 points, without side effects or increase in daytime blood pressure.

Better, a key sign of kidney function improved significantly, too, Dr. Roberto Minutolo of the Second University of Naples reports this month in the American Journal of Kidney Diseases. It’s the latest research in the field of chronotherapy: How our bodies’ internal rhythms make certain diseases worse at certain times of the day, and in turn affect how to time treatments. While the Italian study is too small for proof, similar studies from Europe also back a bedtime switch for non-dippers. The work is catching the attention of U.S. hypertension specialists, and now doctors at Baltimore’s Johns Hopkins University are planning a larger study to see if a bedtime switch really could give certain people healthier hearts and kidneys.

How big a problem is non-dipping?

“I think it’s huge,” says Hopkins’ Dr. Lawrence Appel. “This is our best lead” into why black Americans with kidney disease, in particular, tend to worsen despite treatment. Appel found 80 percent of black kidney patients in a recent study were non-dippers. Most startling, 40 percent had nighttime blood pressure that was even higher than daytime levels. Two-thirds of chronic kidney disease patients, and at least 10 percent of the general population, are estimated to be non-dippers, says Dr. Joseph Vassalotti of the National Kidney Foundation.

One theory is that their bodies have trouble excreting salt. Yet few patients have ever heard of the problem — and few doctors know who is affected. Most people get their blood pressure checked only during the day. A 24-hour blood pressure monitor can tell but is rarely used, partly because insurance seldom pays for the extra visit to download and diagnose the readings.

And most patients who take several once-a-day pills swallow them all in the morning, meaning they all start wearing off around the same time, says Dr. Gina Lundberg of St. Joseph’s Hospital in Atlanta.

“It does make good sense to take some in the morning and some in the evening,” says Lundberg, a spokeswoman for the American Heart Association. Everyone has an internal clock, determined by genes, that affects health. Many of these biological rhythms are circadian, meaning they fluctuate on a 24-hour cycle.

Consider how that can affect the timing of treatments. Some older “statin” pills fight cholesterol best if taken at bedtime; they target a liver enzyme that’s most active at night. Asthma attacks are more frequent at night, and the stomach secretes more heartburn-causing acid at night, affecting some patients’ dosing requirements. Researchers even are studying how to better time certain cancer chemotherapies and allergy treatments. The best-known example: Blood pressure jumps in the early morning hours, as the awakening body produces more stress hormones. That’s also why heart attacks and strokes are most common in the morning.

The nighttime dipping problem has gotten far less attention. The new Italian study marks an important advance, says Dr. Mahboob Rahman of the University Hospitals of Cleveland. “We know now that you can change medication timing and lower blood pressure at night,” he explains. That doesn’t mean everyone should switch willy-nilly to bedtime dosing. Morning may be best for people on just one drug, and no one yet knows if the switch truly gives non-dippers better overall health. “That’s the million-dollar question,” Rahman cautions. Still, Lundberg says it’s worth asking your doctor how to time doses, saying one at night for someone taking multiple medicines couldn’t hurt.


High Dairy in Childhood Linked with Cancer Risk

Children who consume high levels of diary products may have a greater risk of developing colorectal cancer in adulthood, study findings suggest.

Among nearly 5,000 individuals followed for an average of 65 years, those who grew up in families reporting the highest levels of dairy consumption — nearly 2 cups per day — had close to three-times the risk of colorectal cancer compared with those from families reporting the lowest intake, Dr. Jolieke C. van der Pols and colleagues report.

The level of milk consumption in the high-diary group was similar to the estimated average daily intake of children in the United States, van der Pols, of the University of Queensland, Brisbane, Australia, and colleagues noted.

Links between colorectal cancer risk and childhood exposure to dairy products have not been previously evaluated, the researchers said.

Using data from a study of weekly food consumption in families living in England or Scotland from 1937 to 1939, the researchers estimated the daily dairy intake ranged from less than half a cup at the lowest to nearly 2 cups at the highest. Nearly all, 94 percent, of the diary produces came from drinking milk, they report in the American Journal of Clinical Nutrition.

Among the 4,374 individuals still available for follow-up between 1948 and 2005, the investigators identified 35 registrations and 41 deaths from colorectal cancer.

An increased risk of colorectal cancer among those who consumed the highest amounts of dairy during childhood was still seen after the investigators adjusted the data for potentially influential factors such as meat, fruit, and vegetable consumption; and socioeconomic status.

However, van der Pols’ group cautions that more complete life-course assessments comparing dairy intake with related dietary and lifestyle factors must be completed before definitive conclusions can be made for dairy intake in childhood.

The American Journal of Clinical Nutrition, December 2007.


Depression Might Influence Breast Cancer Risk

Depression appears to somewhat heighten the risk of breast cancer, but it has no significant association with lung, colon or prostate cancer, according to a review of the medical literature conducted by Dutch researchers. “Depression is related to a slightly increased risk of cancer,” investigator Dr. Marjan van den Akker told Reuters Health. “The relation with breast cancer gets stronger with a longer follow-up period.” van den Akker, of Maastricht University, and colleagues came to this conclusion after examining data from 13 studies involving more than 127,000 patients. Their findings are published in the journal Clinical Practice and Epidemiology in Mental Health.

Based on eight studies with complete data, the researchers calculated that the overall risk of cancer was increased by 12 percent in individuals with depression. Based on data from seven studies that looked at a mixture of factors, no significant association was seen between depression and the development of breast cancer.

However, analysis of a subgroup of studies that included at least 10 years of follow-up showed a significant association — patients with depression had a 2.5-fold increased risk of developing breast cancer compared with under-pressed patients. “With the evidence available at this moment, it’s difficult to disentangle the possible effects of depression and antidepressants on the occurrence of subsequent cancer,” continued van den Akker. “It’s not yet possible to translate these results into preventive interventions,” she concluded.

Clinical Practice and Epidemiology in Mental Health, December 3, 2007.


Lose Weight by Getting Off Your Duff Literally!

People may be overweight simply because they sit too much, according to scientists at the University of Missouri. They found that exercise alone isn’t enough to take off extra pounds they discovered that the enzymes in our body responsible for burning fat simply shut down when we sit down.

The scientists said the discovery goes far beyond the assumption that people who sit for hours on end in front of the TV or computer are less active and thus prone to gain weight. They said the simple act of sitting on our cans for long periods harms the body in ways which have not been well understood. It was hard to believe at first, said research team leader Marc Hamilton, associate professor of biomedical sciences at the University of Missouri-Columbia. When the team began investigating what happens to fat when we sit for extended periods, they really didn’t expect to find much, and certainly didn’t expect to find anything that turned out to be huge.

In order to avoid the harm caused by sitting for long periods, Hamilton said everyone should stand up and putter. While he doesn’t suggest people quit exercising, he says exercise alone isn’t enough. He says we need to be ever mindful of what we’re doing when we aren’t engaged in exercise, because the ability of the body to get rid of fat stops whenever we stop and sit down.

The researchers injected lab animals with radioactive tracers to follow the fat and find out what happened to it when the animals sat. They found that a fat-splitting enzyme called lipase is suppressed after the animals sat for several hours, and that the fat was transported to adipose tissue, which is connective tissue where fat globules are stored. In other words, the fat was put in a place where it could not easily be burned. Tests with humans showed essentially the same thing: fat was retained; HDL cholesterol, the good kind, was lowered; and the overall rate of metabolism was reduced.

No one yet knows how much we need to get up and move around to keep the fat-splitting enzyme active, but Hamilton says theres soon going to be flood of research by a lot of people to find out. Until all the answers are found, he advises getting up and puttering whenever possible.


Selected segments are reproduced from:

Dr. Mercola’s excellent website: http://www.mercola.com/index.htm

Physicians Committee for Responsible Medicine http://www.pcrm.org