A high intake of trans fats could increase colon cancer risk, according to new research published in the American Journal of Epidemiology.
People who ate the most trans fatty acids were more likely to have pre-cancerous growths or polyps in their colons than those who consumed the least, Dr. Lisa C. Vinikoor of the University of North Carolina in Chapel Hill and colleagues found. "These results provide further support for recommendations to limit consumption of trans-fatty acids," they conclude.
Trans fats are formed by processing vegetable oils to increase their shelf-life, and are found in many baked goods, crackers, snacks and other packaged foods. Eating them increases levels of "bad" LDL-cholesterol, and hence heart disease risk. US food producers are now required to list the amount of trans fat contained in their products, and health authorities recommend people avoid eating trans fats entirely.
While there has been little research on whether trans fats boost colorectal cancer risk, there are many possible ways that they could do so, for example by changing the normal balance of fatty or bile acids in the colon, Vinikoor and her colleagues say.
To investigate a possible link, they looked at 622 people who had colonoscopies at University of North Carolina Hospitals in 2001 and 2002. Study participants were interviewed about their diet, physical activity and other health issues within 12 weeks of having the screening test.
People in the top fourth based on trans-fatty acid consumption, most of whom took in 6.54 grams daily, were 86 percent more likely to have colon polyps than those in the bottom quartile for trans fat intake, for whom median intake was 3.63 g, the researchers found. There appeared to be a threshold effect, with no increased risk seen for people in the bottom three quarters of fatty acid consumption.
Among the 38.5 percent of study participants found to have colon polyps, average trans fatty acid intake was 4.97 g, while most consumed 4.12 g. Average intakes for people who were free of the colon growths was 4.42 g, while the median was 3.61 g.
These results suggest that consumption of high amounts of trans-fatty acid may increase the risk of colorectal polyps, the researchers write, adding that the findings also back current recommendations to limit trans fat intake.
A high intake of trans fats
Metabolic syndrome
Metabolic syndrome, a cluster of conditions that increases the risk of heart disease, stroke and diabetes, in extremely obese patients can be cured by gastric bypass surgery, according to the findings from a new study.
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"Reversibility of metabolic syndrome depends more on the percentage of excess weight lost than on other clinical or demographic characteristics," the research team reports in the journal, Mayo Clinic Proceedings.
To determine the effect of major weight loss on the metabolic syndrome, Dr. Francisco Lopez-Jimenez and colleagues evaluated patients being considered for bypass surgery at the Mayo Clinic in Rochester, Minnesota, between 1990 and 2003.
All patients met at least three of the five criteria for the metabolic syndrome - high levels of triglycerides (a "bad" fat), low levels of high-density lipoprotein "good" cholesterol, increased blood pressure, high blood sugar levels and obesity.
The study group included 180 patients who underwent gastric bypass and 157 patients who did not undergo the procedure, either because they declined surgery, were denied coverage by insurance providers, or did not maintain lifestyle interventions during their evaluation. All patients received medical and dietetic care and extensive counseling about the importance of physical activity.
The mean body mass index (BMI) was 49 in the surgical group and 44 in the nonsurgical group. A normal BMI is considered to be between 18.5 and 24.9.
During an average follow-up of 3.4 years, the prevalence of metabolic syndrome decreased from 87 percent to 29 percent in the surgical group, and from 85 percent to 75 percent in the control group. The authors estimate that the number of patients needed to treat with bypass surgery to cure one patient of metabolic syndrome was 2.1.
Weight loss averaged 44 lbs in the surgical group and 0.2 lbs in the nonsurgical group. Additional analysis showed that the percentage of excess weight lost was the primary factor that determined the resolution of the metabolic syndrome.
"Our study provides robust data to practicing clinicians about the benefits of counseling weight reduction in metabolic syndrome patients," Lopez-Jimenez and his associates conclude.
They recommend "gastric bypass surgery should be considered as a treatment option in patients with metabolic syndrome that has not responded to conservative measures" in those eligible for surgery.
Presidential scholars
Presidential scholars say she appears to be the least experienced, least credentialed person to join a major-party ticket in the modern era.
So unconventional was McCain’s choice that it left students of the presidency literally “stunned,” in the words of Joel Goldstein, a St. Louis University law professor and scholar of the vice presidency. “Being governor of a small state for less than two years is not consistent with the normal criteria for determining who’s of presidential caliber,” said Goldstein.
“I think she is the most inexperienced person on a major-party ticket in modern history,” said presidential historian Matthew Dallek.
That includes Spiro T. Agnew, Richard Nixon’s first vice president, who was governor of a medium-sized state, Maryland, for two years, and before that, executive of suburban Baltimore County, the expansive jurisdiction that borders and exceeds in population the city of Baltimore.
It also includes George H.W. Bush’s vice president, Indiana Sen. Dan Quayle, who had served in the House and Senate for 12 years before taking office. And it also includes New York Rep. Geraldine Ferraro, who served three terms in the House before Walter Mondale chose her in 1984 as the first female candidate on a major-party ticket.
“It would be one thing if she had only been governor for a year and a half, but prior to that she had not had major experience in public life,” Dallek said of Palin. “The fact that he would have to go to somebody who is clearly unqualified to be president makes Obama look like an elder statesman.”
And Alaska is a much smaller state than Illinois, the political base of Barack Obama, whom Republicans have repeatedly criticized for being inexperienced, having served nearly four years in the U.S. Senate after eight in the Illinois state Senate.
“Not to belittle Alaska, but it’s different than the basket of issues you deal with in big, dynamic states,” Dallek said.
Palin has no experience in national office. Before becoming governor in December 2006, she served as a council member and mayor of Wasilla, Alaska, which had a population of slightly more than 5,000 during her time in office.
Brad Blakeman, who ran the 1988 Republican convention for GOP nominee George H.W. Bush, turned the experience question on its head, suggesting that accomplishments in office mean more than time accrued.
“Here’s a governor who may have served two years, but her accomplishments are worth eight,” said Blakeman, citing Palin's work as governor on ethics reform and an Alaska oil pipeline. “She’s got as much experience for being vice president as Barack does to be president.”
But other students of presidential history said that in choosing Palin as his running mate, McCain has reached back to a time when few actually seriously contended that the vice president should be demonstrably prepared to assume the presidency from Day One.
If elected vice president, Palin would appear to have the least amount of experience in federal office or as a governor since John W. Kern, Democrat William Jennings Bryan’s 1908 running mate, who had served for four years in the Indiana state Senate and then four more as city solicitor of Indianapolis. The Democratic ticket lost to Republican standard-bearer William Howard Taft and running mate James S. Sherman by an Electoral College spread of 321-162.
More conventionally in modern times, running mates could boast decades of experience in Washington, from ballot box winners like Dick Cheney, Al Gore, the elder Bush and Mondale to also-rans such as Jack Kemp, Lloyd Bentsen and Joseph I. Lieberman.
These super-credentialed candidates were sometimes chosen, like Joe Biden, to shore up the résumés of candidates with little or no time in Washington, such as Jimmy Carter (Mondale), Bill Clinton (Gore) and Michael Dukakis (Bentsen).
Palin, on the other hand, is a total “wild card,” said Stanford historian David Kennedy.
“If she had been around for two terms as governor — or been a senator — it would have been an incredible choice,” said historian Doris Kearns Goodwin. “Who else could he have found who appealed to the conservative base … and as someone who was a reformer?”
That’s not to say Palin will be a dud on the campaign trail.
But out-of-the-box picks in recent years have not usually worked out too well for the top of the ticket. Consider independent candidate Ross Perot’s 1992 running mate, former Navy Adm. James Stockdale, who famously asked at the vice presidential debate with Gore and Quayle, “Who am I? Why am I here?”
“He took the wind out of Perot’s sails, and Perot could have done even better” than the 19 percent he garnered, Dallek said.
A bad running mate pick can even put a successful presidential ticket in question. The 1988 Bush-Quayle victory over Dukakis and Bentsen came in spite of Quayle’s frequent campaign trail gaffes and questions about his military service in the Vietnam era and other controversies. Bush handlers largely relegated Quayle to small-town audiences that would attract little media attention.
“Quayle — it threw off the momentum for some weeks,” said Goodwin. “One has to hope for McCain’s sake that [Palin] has been fully vetted.”
“The first thing that hits me,” said Stephen Hess of the Brookings Institution, "is that it suggests that John McCain is a gambler. This is a high-roller decision.”
“The next thing you have to ask yourself: Is it worrisome to have a gambler in the Oval Office? That’s an important question," he said, “perhaps more important than anything else today.”
Influenza vaccination
While influenza vaccination does provide protection against catching the flu, it does not have a major impact on death in the elderly, contrary to what some studies have suggested, a new study suggests.
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In prior studies, an impressive 50 percent reduction in death from any cause had been noted in elderly people who got a flu shot, but some researchers were skeptical of this degree of benefit, suggesting that it may have been the result of the "healthy user effect." The new study supports this line of thinking.
The study included more than 700 elderly people, half of whom had gotten a flu shot and half of whom had not. After controlling for a variety of factors that were largely not considered or simply not available in previous studies, the researchers concluded that any death benefit "if present at all, was very small and statistically non-significant and may simply be a healthy-user artifact that they were unable to identify."
"The healthy-user effect," study chief Dr. Sumit Majumdar of the University of Alberta in Edmonton, Canada explained in a statement, "is seen in what doctors often refer to as their 'good' patients -- patients who are well-informed about their health, who exercise regularly, do not smoke or have quit, drink only in moderation, watch what they eat, come in regularly for health maintenance visits and disease screenings, take their medications exactly as prescribed -- and quite religiously get vaccinated each year so as to stay healthy. Such attributes are almost impossible to capture in large scale studies using administrative databases."
"Over the last two decades in the United Sates, even while (flu) vaccination rates among the elderly have increased from 15 to 65 percent, there has been no commensurate decrease in hospital admissions or all-cause mortality," added co-investigator Dr. Dean T. Eurich, who is also with the University of Alberta.
"Further, only about 10 percent of winter-time deaths in the United States are attributable to influenza, thus to suggest that the vaccine can reduce 50 percent of deaths from all causes is implausible in our opinion," he added.
The study involved 352 patients given the vaccine and 352 matched control subjects. Overall, 85 percent of patients were over 64 years of age. Severe pneumonia was seen in 29 percent of patients and 12 percent of the patients died.
Flu vaccination was, in fact, associated with reduced mortality of about 50 percent (8 percent vs. 15 percent mortality in the vaccinated and unvaccinated groups, respectively), and this finding did not change after accounting for age, gender, or co-existing illnesses.
However, after adjusting for other potential confounders, including functional and socioeconomic status, the mortality reduction was weakened and no longer statistically significant.
"Previous studies were likely measuring a benefit not directly attributable to the vaccine itself, but something specific to the individuals who were vaccinated -- a healthy-user benefit or frailty bias," Eurich concluded in a statement.
Drunken
Drunken-driving deaths fell in 32 states in 2007, the government reported Thursday, but alcohol-related fatalities increased among motorcycle riders in half the states.
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Nearly 13,000 people were killed in crashes in which the driver had a blood alcohol concentration of 0.08, the legal limit in the United States, or at higher levels.
Overall, alcohol deaths were down nearly 4 percent compared with 2006, when nearly 13,500 people died on the highway.
Transportation Secretary Mary Peters said she was disappointed by the increase in deaths involving drunk motorcycle riders. A total of 1,621 motorcyclists were killed in alcohol-impaired crashes in 2007, an increase of 7.5 percent.
Motorcycle riders have been featured in the government's $13 million advertising campaign surrounding the Labor Day holiday. Law enforcement agencies are increasing their enforcement against drunken driving during the end of the summer.
Dean Thompson, a spokesman for the Motorcycle Safety Foundation, said riders who conduct training courses always stress the dangers involved in drinking alcohol before riding.
"The skill set you need in terms of the coordination and balance and things like that, you cannot choose to drink and ride. It's just the wrong choice to make," he said.
Among the states, California had 117 fewer alcohol-impaired driving deaths last year, the largest decrease in the nation. Texas had 108 fewer deaths and Arizona's fatalities dropped by 63 deaths.
California conducted more than 1,000 sobriety checkpoints during the year and encouraged motorists to dial 911 on their cell phones if they spot a potentially drunken driver, said Christopher Murphy, who leads the state's traffic safety office.
"Our vision is really toward zero deaths — everyone counts, so we're not exactly celebrating these numbers," said Murphy, who leads the Governors Highway Safety Association.
North Carolina had 66 more deaths, the most among states, followed by South Carolina with 44 fatalities.
In addition to North Carolina and South Carolina, alcohol-impaired deaths increased in Alabama, Alaska, Delaware, Maine, Massachusetts, Minnesota, Montana, Nebraska, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Virginia, West Virginia, Wisconsin and the District of Columbia.
The latest data followed calls from dozens of college presidents to consider lowering the drinking age from 21 to 18, arguing that the laws lead to binge drinking on campus.
Mark Rosenker, acting chairman of the National Transportation Safety Board, said Thursday he opposed the administrators' effort.
"Age 21 drinking laws have been proven time and again effective in preventing deaths and injuries," Rosenker said. "Repealing them is a terrible idea."
Researchers studying
Researchers studying people with a rare genetic disorder have identified a brain chemical that may play a role in appetite and obesity, a finding they say could lead to new drugs to help some obese people.
Previous animal studies had pointed to this chemical, known as BDNF, as helping to regulate appetite and weight, but the new study published on Wednesday in the New England Journal of Medicine is the first to show such a role in people.
"The importance of the finding is that it opens up another avenue for us to develop treatments that might help folks with obesity," said Dr. Jack Yanovski of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, part of the U.S. National Institutes of Health.
A number of substances naturally occurring in the body, including the hormone leptin and neuropeptide Y, are known to affect appetite and obesity, and the findings about BDNF add to the understanding of factors underpinning obesity, he added.
BDNF, which stands for brain-derived neurotrophic factor, is already known to play a role in long-term memory.
"We're looking at a small part of what is really a large and complex puzzle," Yanovski, who helped lead the study, said in a telephone interview. "We guess there are probably about 300 genes that affect body weight in some form or another."
The study involved 33 people with WAGR (pronounced wagger) syndrome, a rare genetic condition that puts one at high risk for eye problems, certain cancer types and mental retardation.
Normally a person has two copies of the gene that controls BDNF. But the researchers found that most of the WAGR syndrome patients -- 19 of them -- were missing one copy of the gene, and thus had low blood levels of BDNF.
Every one of the 19 was obese by age 10 and had a strong tendency to overeat. The 14 other people who had two working copies of the gene were no more likely than the general population to be obese or overeat, the researchers said.
This strongly suggests BDNF is involved in controlling appetite and thus obesity, they said. The release of BDNF in the hypothalamus, a brain structure involved in regulating appetite, may be triggered indirectly by leptin, they added.
Yanovski said drugs that are based on improving low levels of BDNF could help certain obese people who have not had success with other treatments.
Fat cells in obese people
Fat cells in obese people are "sick" compared to those in lean people, a new study shows.
Published in the September issue of Diabetes, a group of researchers from the Temple University School of Medicine analyzed fat samples from the upper thighs of six lean and six obese people.
They found significant differences in the fat cells of the obese participants compared with the lean participants.
"The fat cells we found in our obese patients were deficient in several areas," study author Guenther Boden, the Laura H. Carnell Professor of Medicine and chief of endocrinology, said in Temple press release.
Boden said that the obese people's fat cells showed stress on the endoplasmic reticulum (ER), which helps cells synthesize proteins and monitor how they are folded. When the ER is stressed, Boden explained, it produces several proteins that ultimately lead to insulin resistance. Insulin resistance, in turn, plays a major role in the development of obesity-related conditions.
The differences in the fat cells between obese and lean people may help explain the link between obesity and a higher risk of diabetes, heart disease, and stroke, Boden theorized.
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Trecking
