Archive for January, 2010

Genes Linked to ‘Pot’ Belly

Sunday, January 31st, 2010

New research sheds light on the possible link between the genes you inherit and the size of your belly.

Participants in a French study doubled their risk of having fat around the abdomen if they had a certain genetic trait, and the more of these traits one had, the greater the risk for a pot belly.

The study was looking at metabolic syndrome, a condition in which abdominal obesity, high cholesterol and high blood pressure combine to raise the risk of several diseases such as stroke, heart disease and type 2 diabetes.

The findings are just one more piece of the obesity puzzle, a nutrition specialist said.

“Certainly it adds to the body of knowledge, but we need to look at what it means within the big picture and context of all the other obesity research,” said Lona Sandon, an assistant professor at University of Texas Southwestern Medical Center and spokeswoman for the American Dietetic Association.

Results of the study, which was designed to explore a possible link between genes and metabolic syndrome, are published in the November issue of the Journal of Nutrition.

The researchers followed 1,754 French people for seven and a half years, tracking what they ate. They found that having any one of five genetic traits doubled the risk that a person would have abdominal obesity, and that eating a lot of saturated fats boosted the risk even more. But they also found that having one of the genetic traits didn’t boost the risk of metabolic syndrome.

Sandon said the study doesn’t confirm that the genetic trait directly leads to obesity. The findings, she said, show “an association, not a cause-and-effect.”

Also, she pointed out that while the study found a relationship between the gene and abdominal obesity, some subjects were consuming more than 15.5 percent of their calories from saturated fat.

The current recommendation is 10 percent for most healthy people and 7 percent for those with high cholesterol and other metabolic risk factors for heart disease, she said.

In the larger picture, researchers are beginning to understand how genetics are connected to obesity and “how those genes are affected by environment and food components,” Sandon said.

“The mystery is how do we put this into real health recommendations, and how do multiple genes work together to promote or squelch obesity,” she said. “If there were just one gene related to obesity, the answer might be simple. But we know multiple genes are involved, so it is difficult to make hard and fast conclusions about what people should do with this information.”

When it comes to obesity, the factors of genetics, diet and exercise — or lack thereof — are indeed “highly entangled,” said study co-author Dr. Richard Planells, a professor of biochemistry at University of Aix-Marseille II in France.

What to do? At the moment, genetic tests to track these particular genes aren’t feasible. “Many other genes have to be analyzed before one can design a genetic map,” Planells explained.

Even if there was such a test, “the majority of control is always in your hands,” added Cynthia Sass, a registered dietitian and author in New York City. “Even if you have strong genetic predispositions to obesity or any disease, you are not guaranteed to develop that disease. Given the exact same lifestyle, yes, you will have a higher risk, but the bottom line is that the majority of the risk lies in how you treat your body, and that’s empowering.”

Handwriting Skills May Lag in Kids With Autism

Wednesday, January 27th, 2010

Autistic children are more likely to have handwriting problems, including trouble forming letters, than those without autism, researchers say.

The new study included 28 children, aged 8 to 13. Half of the study participants had autism spectrum disorder, but all of the children scored within the normal range for perceptual reasoning on an IQ test.

The children were asked to copy a scrambled sentence — “the brown jumped lazy fox quick dogs over” — to eliminate any speed advantage for children who were more fluent readers.

Five categories were used to score the participants’ handwriting: legibility, form, alignment, size and spacing. Half of the 14 children with autism earned less than 80 percent of the total possible points, compared with one of 14 children in the group without autism. Nine of the children with autism scored below 80 percent in the form category, compared with two of the children without autism, the researchers reported.

The overall handwriting quality was poorer in children with autism, but all of the children in both groups were able to align, space and size their letters equally well, the study authors noted in their report in the Nov. 10 issue of Neurology.

“Our results suggest that therapies targeting motor skills may help improve handwriting in children with autism, which is important for success in school and building self-esteem,” study author Amy Bastian, of the Kennedy Krieger Institute and Johns Hopkins School of Medicine in Baltimore, said in a news release from the American Academy of Neurology. “Such therapies could include training of letter formation and general training of fine motor control to help improve the quality of their writing.”

Health Tip: Create Baby’s Bedtime Routine

Monday, January 18th, 2010

Babies are never too young to benefit from a bedtime routine, the U.S. National Library of Medicine says.

The agency offers these suggestions for developing bedtime habits from the start:
Don’t give your baby a bottle in bed. Make sure the last bottle of the day is given a sufficient amount of time before bed.
Enjoy quiet relaxation time with your baby.
Put baby to bed when sleepy, but not when he or she is actually asleep. This way, baby gets used to falling asleep alone.
When baby cries, speak in a soothing tone. Or rub baby’s back until calm. But don’t pick baby up.
Avoid turning lights on when you feed baby in the middle of the night.
Whatever your routine, make sure you’re consistent, and try to ensure that both of you enjoy it.
Don’t sleep in the same bed with a baby that’s 12 months or younger. This may increase the risk of sudden infant death syndrome (SIDS).

Germs Mingle Most on Palms, Feet, Forearms

Friday, January 15th, 2010

A new “atlas” of bacterial life on and within the human body has uncovered the fact that your palms, feet and forearms are a veritable United Nations of germs.

The scientists, using sophisticated gene-sequencing technologies, pinpointed specific bacterial types and where they like to thrive on and within the body. They found a wide variability of bacteria, depending on the spot on the body. They also found that bacterial colonies differed person to person, with each individual carrying his or her own “personalized” assortment of microorganisms.

“We’ve always known that there are microbes on us and in us,” said study author Noah Fierer, an assistant professor of microbial ecology at the University of Colorado at Boulder. “But we weren’t always able to isolate them and differentiate them from each other. With these new techniques, we can.”

“Each of us is really an archipelago of distinct habitats, at least as far as bacteria are concerned,” added senior study author Robert Knight, an assistant professor of chemistry and biochemistry and computer science at the University of Colorado. “It’s truly amazing how different the sites within the same body are, and how different the corresponding sites on different people are.”

The team’s work is being published Nov. 5 in the online version of Science. The study builds on earlier research, including a 2008 study that found that women had a greater diversity of bacteria on their palms than men.

The mapping project focused on seven to nine men and women, who were examined four times each over a three-month period. Researchers swabbed 27 different sites, searching for bacteria in virtually every nook and cranny, from hair to ear wax, mouth to nostril and trunk and legs.

So, where are the most popular places for bacteria to hang out? They seem to like the gut (no surprise there), forearms, palms, index fingers, the backs of the knees and soles of the feet, according to the study. At least that is where some of the most diverse and thriving colonies take root.

Some bacterial communities appeared to strongly prefer one body spot over another. For example, when the scientists transplanted microbial groupings from the forearm to the forehead, the germs failed to thrive. But doing the reverse — transplanting communities from forehead to forearm — didn’t seem to impede bacterial growth.

Researchers focused on bacterial diversity rather than bacterial quantity. There are thousands of bacterial types, but certain ones seemed prominent in the study, said Fierer. Four bacterial groups stood out — Actinobacteria, Firmicutes, Proteobacteria and Bacteroidetes — and they were relatively stable over time. Individual bacterial types included the Streptococcus and Staphylococcus bacteria.

In some ways, the mapping efforts spurs more questions than it answers. Researchers are not sure why the forearms and other body parts attract so much microbial diversity. Also, it is not clear whether the different strains compete with each other or live in a kind of bacterial harmony.

Researchers also want to know whether people are born with these bacterial colonies or develop them after birth, through external contact with their mothers and during the delivery process. Even more fascinating is why each person has his or her own blend of bacteria — much like a fingerprint. Perhaps diet, climate, locale or a combination of variables are responsible for each person’s unique bacterial make-up, said Fierer.

Most important, researchers want to know how the colonies impact health and whether they can be harnessed in some way to treat disease. In the future, for example, microbial mapping could lead to routine screening of patients as a way to record a baseline of their normal microbial communities. Any later deviation could be a sign of disease.

“Our ultimate goal is to devise strategies for personalized medicine, based not on the human genome, where we are all 99.9 percent identical, but on the human microbiome, where we are 80 to 90 percent different from one another,” added Knight.

Red, processed meats linked to prostate cancer

Tuesday, January 12th, 2010

Men who eat a lot of red meat and processed meats may have a higher risk of developing prostate cancer than those who limit such foods, a large study of U.S. men suggests.

Researchers at the National Cancer Institute found that among more than 175,000 men they followed for nine years, those who ate the most red and processed meats had heightened risks of developing any stage of prostate cancer, or advanced cancer in particular.

The findings, reported in the American Journal of Epidemiology, add to a conflicting body of research on meat intake and prostate cancer risk. Because studies over the years have come to different conclusions, experts generally consider the evidence linking red and processed meats to the disease to be limited and inconclusive.

These latest findings do not settle the question. But they do suggest that processed red meats and high-heat cooking methods — namely, grilling and barbecuing — may be particularly connected to prostate cancer risk, according to Dr. Rashmi Sinha and her colleagues at the NCI.

For the study, the researchers followed 175,343 U.S. men between the ages of 50 and 71 who were surveyed about their diets — including how much and what type of meat they typically ate, as well as the cooking methods they used.

The researchers used that information to estimate the levels of certain potentially cancer-promoting chemicals in the men’s diets.

Over the next nine years, 10,313 study participants developed prostate cancer and 419 died from the disease.

Overall, the researchers found, the 20 percent of men with the highest intakes of red meat, which in this study included beef and pork, were 12 percent more likely than those who consumed the least to develop prostate cancer. That’s after a range of other factors, like smoking, exercise habits and education, were taken into account.

There was a stronger connection to advanced prostate cancer — with that risk being almost one-third higher among those who ate the most red meat versus those who ate the least.

Similar findings were seen with processed meat. But when the researchers broke the men’s diet information down further, they found that red processed meats — like bacon and red-meat sausage and hot dogs — were related to higher prostate cancer risk, while white processed meats, like poultry cold cuts, were not.

When it came to cooking methods, the only one that was linked to prostate cancer was grilling/barbecuing, Sinha’s team found.

The finding is in line with the theory that meats cooked at high temperatures may be particularly linked to cancer because the cooking process produces certain chemicals — including polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines — that are known to cause cancer in animals.

Giving further support to that idea, the researchers found that higher dietary levels of a PAH called benzo-alpha-pyrene were related to a higher risk of prostate cancer. A similar pattern emerged when the investigators looked at men’s intake of nitrites and nitrates — chemicals used to preserve and flavor processed and cured meats like ham, bacon and sausage.

In the body, nitrites and nitrates can promote the production of potentially cancer-promoting chemicals called nitrosamines.

Taken together, Sinha’s team writes, the findings point to potential mechanisms by which certain meats could promote prostate cancer.

They also highlight the importance of studying the relationship between specific types of meat and prostate cancer risk, the researchers say.

Further studies, they conclude, are still needed to establish whether certain meats, and chemicals in those foods, are in fact risk factors for prostate cancer.