Monday, December 28, 2009

Pistachios Reduce Risk of Lung Cancer

“Pistachios are one of those good-for-you nuts, and 2 ounces per day could be incorporated into dietary strategies designed to reduce the risk of lung cancer without significant changes in body mass index,” said Ladia M. Hernandez, senior research dietitian in the Department of Epidemiology at the University of Texas M. D. Anderson Cancer Center.

It's nice to know that there is a delicious tasting nut out there that actually has healthy properties, and in this case, is showing scientists a considerable benefit when consumed by those who would otherwise be at risk of certain cancers.

A diet that incorporates a daily dose of pistachios may help reduce the risk of lung and other cancers, according to data presented at the American Association for Cancer Research Frontiers in Cancer Prevention Research Conference, held Dec. 6-9. This is likely because vitamin E provides a degree of protection against certain forms of cancer. Higher intakes of gamma-tocopherol, which is a form of vitamin E, may reduce the risk of lung cancer. Pistachios are loaded with gamma-tocopherol.

“Pistachios are a good source of gamma-tocopherol. Eating them increases intake of gamma-tocopherol so pistachios may help to decrease lung cancer risk,” said Hernandez, the main author.

Pistachios are known to provide a heart-healthy benefit by producing a cholesterol-lowering effect and providing the antioxidants that are typically found in food products of plant origin. Hernandez and colleagues conducted a six-week, controlled clinical trial to evaluate if the consumption of pistachios would increase dietary intake and serum levels of gamma-tocopherol. Many experts will tell you that it is better to get your vitamin E through natural food sources than via supplements.

A pistachio-rich diet could potentially help reduce the risk of other cancers from developing as well, according to Hernandez.

“Because epidemiologic studies suggest gamma-tocopherol is protective against prostate cancer, pistachio intake may help,” she said. “Other food sources that are a rich source of gamma-tocopherol include nuts such as peanuts, pecans, walnuts, soybean and corn oils.” The study, conducted at Texas Woman’s University included 36 healthy participants who were randomized into either a control group or the intervention group consisting of a pistachio diet. There were 18 participants in the control group and 18 in the intervention group.

Hernandez and colleagues found a significant increase in energy-adjusted dietary intake of gamma-tocopherol at weeks three and four in those on the pistachio diet compared with those on the control diet. The similar effect was seen at weeks five and six among those on the pistachio diet compared with those on the control diet. For those on the pistachio diet, cholesterol-adjusted serum gamma-tocopherol was significantly higher at the end of the intervention period compared to baseline.


Wednesday, December 16, 2009

Celebrex Undermines Aspirin’s Anti-Clotting Action

Researchers at the University of Michigan Health System suggest that it may not be a good idea to combine the pharmaceutical drug Celebrex with a daily low-dose aspirin regimen. Millions of Americans take Celebrex for arthritis or other pain. Many, if they are middle-aged or older, also take a low-dose aspirin tablet daily to reduce the risk of heart attack and stroke. Yet they may be getting little protection, because Celebrex keeps the aspirin from doing its job effectively.

Doctors frequently advise daily low-dose aspirin (81 mg) for patients who have heart conditions, notably a serious form of angina known as unstable angina, or for patients who are at risk of second heart attacks. Aspirin is well-known for its ability to discourage formation of blood clots that can lead to heart attack and stroke. In addition, arthritis patients who take Celebrex regularly are often put on low-dose aspirin because this is thought to counteract Celebrex’s own potential clot-promoting effect.

But there is a problem with this combination. In laboratory studies, University of Michigan researchers found that several drugs in the class to which Celebrex belongs interfere with aspirin’s ability to discourage blood clots, if the aspirin is taken in low doses. These results appear in the journal Proceedings of the National Academy of Sciences.

“There are many people who take low-dose aspirin, perhaps as many as half of men over 50. If they are also prescribed Celebrex for arthritis or other pain, our results suggest that the Celebrex will probably interfere with the aspirin’s action,” says William L. Smith, Ph.D., the study’s senior author and chair of the biochemistry department at the University of Michigan Medical School.

“The greatest risk is having people take Celebrex who are taking aspirin for cardiovascular problems that are known to be mitigated by aspirin, including patients with unstable angina or those at risk for a second heart attack,” he says. In unstable angina, small clots form in arteries and interfere with blood flow. Previous studies of healthy subjects found no ill effect on blood clotting when Celebrex was combined with aspirin at higher doses, specifically a daily “regular” aspirin tablet (324 mg), Smith notes. So it may be that a higher aspirin dose, or spreading out the time between taking low-dose aspirin and Celebrex, will allow aspirin to be effective.

For many people, however, Aspirin’s undesirable effects on the gastrointestinal tract at higher doses when taken long-term would have to be taken into account.

More research is ongoing, as it will be important to determine if a balance in dose and/or dose regimens can be found so that aspirin and Celebrex can both be effective.


Saturday, December 5, 2009

Hibiscus a Possible Help for Hypertension

Hibiscus, an easily accessible and popular herb, has been shown in a recent study to be very good for reducing blood pressure in hypertensive people.

Hibiscus flowers have been used historically to treat high blood pressure, liver disease, and fever. It now turns out that in addition to ascorbic and citric acid (vitamin C), they contain a number of important vasoactive alkaloids, anthocyanins and quercetin, which may lay behind this blood-pressure benefit.

The study referred to was designed to compare the blood pressure lowering effects of “Sour tea,” made from Hibiscus sabdariffa, with ordinary black tea (Camellia sinensis) in type II diabetics with mild high blood pressure. Sixty such patients, none of whom were taking antihypertensive or lipid-lowering medications, were randomly assigned to drink one cup of Sour tea or black tea twice daily for one month. Each infusion was to be made with one tea sachet weighing 2 gm, placed in a teapot with 240 ml boiling water, and steeped for 20–30 minutes. They were permitted to add one cube of sugar.

The average systolic blood pressure (SBP) in the Hibiscus group decreased from 134.4 ± 11.8 mmHg at baseline to 112.7 ± 5.7 mmHg after 1 month, a robust 16% reduction. Among the black tea drinkers, the average SBP actually increased over the month, from 118.6 ± 14.9 mmHg at baseline to 127.3 ± 8.7 mmHg, a 7.3% rise. There were no statistically significant changes in mean diastolic blood pressure in either group.

Overall, the interventions were deemed “effective” (i.e., producing significant decreases in systolic pressure) in 48% of the Sour tea patients but only 15% of the black tea patients. The study was written up in the Journal of Human Hypertension, 2009; 23: 48–54). The findings are highly supportive of Hibiscus as a remedy for mild blood pressure elevations, in which the risks and costs of drug therapy may not be outweighed by their expected benefits, or in cases where a patient does not want to begin pharmaceutical treatment.


Thursday, December 3, 2009

Cigarettes Harbor Many Bacteria

A new international study conducted by centers in both the USA and France shows that cigarettes are "widely contaminated" with bacteria, including some known to cause disease in people. This work was done by researchers at the University of Maryland as well as at the Ecole Centrale de Lyon in France.

The research team describes the study as the first to show that "cigarettes themselves could be the direct source of exposure to a wide array of potentially pathogenic microbes among smokers and other people exposed to secondhand smoke." Their study will appear in an upcoming edition of the journal Environmental Health Perspectives and the manuscript has been posted online.

Lead researcher Amy R. Sapkota, an assistant professor at UMD (Maryland) says, "We were quite surprised to identify such a wide variety of human bacterial pathogens in these products. The commercially-available cigarettes that we tested were chock full of bacteria, as we had hypothesized, but we didn't think we'd find so many that are infectious in humans," explains Sapkota, who holds a joint appointment with the University's Maryland Institute for Applied Environmental Health and the department of epidemiology and biostatistics.

"If these organisms can survive the smoking process - and we believe they can - then they could possibly go on to contribute to both infectious and chronic illnesses in both smokers and individuals who are exposed to environmental tobacco smoke," Sapkota adds. Obviously scientists feel they need to learn more about the bacterial content of cigarettes, because these products are still used by more than a billion people worldwide.

Among the study's findings and conclusions:

* Commercially available cigarettes show a broad array of bacterial diversity, ranging from soil microorganisms to potential human pathogens;
* This is the first study to provide evidence that the numbers of microorganisms in a cigarette may be as "vast as the number of chemical constituents;"
* Hundreds of bacterial species were present in each cigarette, and additional testing is likely to increase that number significantly;
* No significant variability in bacterial diversity was observed across the four different cigarette brands examined: Camel; Kool Filter Kings; Lucky Strike Original Red; and Marlboro Red;
* Bacteria of medical significance to humans were identified in all of the tested cigarettes and included Acinetobacter (associated with lung and blood infections); Bacillus (some varieties associated with food borne illnesses and anthrax); Burkholderia (some forms responsible for respiratory infections); Clostridium(associated with foodborne illnesses and lung infections); Klebsiella (associated with a variety of lung, blood and other infections); and Pseudomonas aeruginosa (an organism that causes 10 percent of all hospital-acquired infections in the United States).

This research might account for the fact that the respiratory tracts of smokers are characterized by higher levels of bacterial pathogens.


Tuesday, December 1, 2009

Loneliness Can be Contagious

Research at the University of Chicago, the University of California San Diego and Harvard shows that loneliness can spread among groups of people like a bad cold.

Using data from a large-scale study that has been following health conditions for more than 60 years, a team of scholars found that lonely people tend to share their loneliness with others. Gradually over time, a group of lonely, disconnected people moves to the fringes of social networks.

“We detected an extraordinary pattern of contagion that leads people to be moved to the edge of the social network when they become lonely,” said University of Chicago psychologist John Cacioppo, one member of the study team and one of the nation’s leading scholars of loneliness. “On the periphery people have fewer friends, yet their loneliness leads them to losing the few ties they have left.”

Other members of the study team were James Fowler, Associate Professor at the University of California San Diego, and Nicholas Christakis, Professor of Medicine in the Harvard Medical School. Before relationships are severed, people on the periphery transmit feelings of loneliness to their remaining friends, who also become lonely. “These reinforcing effects mean that our social fabric can fray at the edges, like a yarn that comes loose at the end of a crocheted sweater,” said Cacioppo.

Because loneliness is associated with a variety of mental and physical diseases that can shorten life, Cacioppo said it is important for people to recognize loneliness and help those people connect with their social group before the lonely individuals move to the edges.

These findings were published in the article, “Alone in the Crowd: The Structure and Spread of Loneliness in a Large Social Network,” published in the December issue of the Journal of Personality and Social Psychology. For the study, the team examined records of a study which has been ongoing since 1949, including more than 5,200 people in what was originally a study of cardiovascular risk.

The study has since been expanded to include about 12,000 people, as the children and the grandchildren of the original group and others have been included to diversify the population sample. This study now includes more tests, including measures of loneliness and depression. The second generation in the study, which includes 5,124 people, was the primary focus of the loneliness research.

Researchers kept in touch with the subjects every two to four years and collected names of friends who knew the subjects. Those records became an excellent source of information about the people’s social networks.

By constructing graphs that charted the subjects’ friendship histories and information about their reports of loneliness, researchers were able to establish a pattern of loneliness that spread as people reported fewer close friends. The data showed that lonely people “infected” the people around them with loneliness, and those people moved to the edges of social circles. The team found that the next-door neighbors in the survey who experienced an increase of one day of loneliness a week prompted an increase in loneliness among their neighbors who were their close friends. The loneliness spread as the neighbors spent less time together.

Women, who are more likely to need emotional support, were more likely to report “catching” loneliness from others than were men. People’s chances of becoming lonely were more likely to be caused by changes in friendship networks than changes in family networks.

Research also shows that as people become lonely, they become less trustful of others, and a cycle develops that makes it harder for them to form friendships. Societies seem to develop a natural tendency to shed these lonely people, a pattern which makes it all the more important to recognize loneliness and deal with it before it spreads.

“Society may benefit by aggressively targeting the people in the periphery to help repair their social networks and to create a protective barrier against loneliness that can keep the whole network from unraveling,” the authors said.