THURSDAY, Jan. 26 (HealthDay News) -- Infants younger than a year old who are at risk of developing autism may already have telltale brain responses when another person looks at or away from them, the results of a new study indicate.

The researchers say that the findings suggest that assessing brain responses in infants as young as 6 months may one day help predict whether they'll develop autism at a later age. Currently, firm diagnoses of autism are made only after a child is 2 years old, according to the study in the Jan. 26 online edition of Current Biology.

"Our findings demonstrate for the first time that direct measures of brain functioning during the first year of life associate with a later diagnosis of autism -- well before the emergence of behavioral symptoms," study author Mark Johnson of Birkbeck College, University of London, said in a journal news release.

The study included infants aged 6 to 10 months who had an increased risk of developing autism because they had an older brother or sister with the disorder. The researchers monitored the infants' brain activity while they viewed faces that switched between looking at them and looking away from them.

Previous research has shown that characteristic patterns of brain activity occur in a normal response to eye contact with other people, a response that's crucial for face-to-face social interaction. Older children with autism have unusual patterns of eye contact and of brain responses to social interactions that involve eye contact.

This study found that the brains of the infants at risk of developing autism already process social information in a different way than typically developing children.

"At this age, no behavioral markers of autism are yet evident, and so measurements of brain function may be a more sensitive indicator of risk," Johnson said.

However, the researchers noted that not all the babies who showed these differences in brain function were later diagnosed with autism, and vice versa. Brain-function measuring would need to be further adjusted and used alongside other methods to serve as an accurate predictor of autism in a clinical setting, the researchers said.

More information

The U.S. National Institute of Neurological Disorders and Stroke has more about autism.

WEDNESDAY, Jan. 25 (HealthDay News) -- It's well-documented that healthy foods such as fresh fruits and vegetables tend to cost more than "junk" foods such as chips and cookies, a phenomenon that's often cited as a contributing factor to the U.S. obesity epidemic.

But a new study conducted in YMCAs found that healthy snacks aren't always more expensive, and in some cases are even more economical.

From 2006 to 2008, researchers from Harvard School of Public Health evaluated the snacks offered to kids at 32 YMCAs in four cities in the U.S. Pacific Northwest, South, Midwest and East.

The YMCA sites were participants in a program called the YMCA/Harvard Afterschool Food and Fitness Project, designed to improve the diets and boost physical activity among kids aged 5 to 12 attending the Ys' after-school programs. The project set out standards for snacks served at YMCAs, including: serving water instead of sugar-sweetened beverages, offering whole grains and a fruit or vegetable with each snack and avoiding trans fats.

"One of the questions we had was what kind of financial burden are we putting on them to ask them to put these healthier foods into place, because it's known that healthy foods are more expensive," said Rebecca Mozaffarian, project manager for the YMCA/Harvard program.

The average cost per snack was 57 cents, with prices ranging from 47 cents in the Midwest and Northeast to 78 cents in the Pacific Northwest.

As expected, snacks that met the healthy eating standards cost 50 percent more than those that didn't.

However, some YMCAs found ways of mixing and matching combinations that both met the healthy eating standards and kept costs at or even below what it would cost to serve a less healthy alternative.

For example, serving water instead of fruit juice significantly reduced the price of a snack. Instead of the fruit juice, Ys could serve water and a banana or apple slices and water, and the snack had the same calorie count at a lower cost. The whole fruit has the added nutritional benefits of fiber and helping kids feel fuller, longer than juice, Mozaffarian said.

Or, for example, water and cheese is less expensive than serving chocolate milk, and the cheese contains less sugar.

Other areas where Ys could make improvements without adding to cost were substituting whole grains, in foods such as Triscuits, Wheat Thins and Cheerios, for refined grains such as graham crackers and Saltines.

And while snacks that included canned or frozen vegetables were on the pricy side, snacks including fresh vegetables, such as carrots and celery, were not.

The study is in the February issue of the journal Preventing Chronic Disease.

Some YMCAs in low-income areas are reimbursed by the federal government for snacks at a rate of 74 cents per snack per child. Using this as a target number, researchers identified a dozen healthy snack combinations that fall under that price. Those include: carrots, hummus and water; apples, cheese slices, water; whole wheat bread, green peppers, turkey slices, water; Craisins (dried cranberry snacks), string cheese, Wheat Thins, water; and applesauce, popcorn, 1 percent milk, water.

Joy Dubost, a registered dietitian and spokeswoman for the Academy of Nutrition and Dietetics, called the study "well-conducted." However, the five criteria used to determine what qualifies as a healthy snack option aren't as comprehensive as she would like.

For example, tortilla chips count as a whole grain and therefore meet the criteria for a healthy snack option, but they're also full of saturated fat, which may contribute to heart disease over the long term.

Applesauce counts as a fruit, but it would be better if the guidelines specified that the after-school programs choose applesauce without added sugar, she said.

In addition to addressing saturated fats and added sugars, the healthiest after-school snack would take into account calories and sodium, which many American children get too much of as well, Dubost said.

"It's a step in the right direction, but they could be doing a little bit more," she said.

More information

For more on choosing healthy snacks for children, visit Food and Fun After School  .

TUESDAY, Jan. 24 (HealthDay News) -- Exposure to high levels of a group of common household chemicals may impair children's immunity, a new study suggests.

The team of researchers, from the United States and Denmark, showed that elevated exposures to perfluorinated compounds (PFCs) in early childhood was associated with a reduced immune response to two routine immunizations.

"We found that PFC pollution is apparently making the immune system more sluggish, so that it doesn't react as vigorously to vaccines as it should," said study author Dr. Philippe Grandjean, an adjunct professor of environmental health at the Harvard School of Public Health in Boston.

The findings appear in the Jan. 25 issue of the Journal of the Medical Association.

PFCs are commonly used in a wide range of household products including nonstick cookware, carpets, upholstery and food packaging such as microwave popcorn bags; previous research has found that the chemicals are present in most people's bloodstreams.

Other recent studies have linked increased exposure to the chemicals with early menopause and elevated cholesterol levels. But Grandjean said this is the first study in humans to find an association between high levels of PFCs in the blood and an impaired immune response.

"What we don't know is whether this association represents a general immune system dysfunction, and if it has implications in regards to infections, allergies or even cancer," Grandjean said. "We are looking at something that appears to be just the tip of the iceberg, and we'd very much like to know what the rest of the iceberg looks like."

For the study, Grandjean and his colleagues followed 587 children born in the Faroe Islands between 1999 and 2001. In the Faroes, located in the North Atlantic Sea between Iceland and Norway, frequent intake of seafood is associated with increased exposure to PFCs.

To examine the chemicals' effects on immunity, the research looked at antibody levels to the tetanus and diphtheria vaccines, which children in the Faroes are given at 3, 5 and 12 months of age, with a booster shot at 5 years of age. The children's prenatal exposures to five kinds of PFCs were measured by conducting blood tests on their mothers in the last weeks of their pregnancies. Postnatal exposure was assessed through blood tests at age 5. The researchers then measured serum antibody concentrations against tetanus and diphtheria vaccines at ages 5 and 7.

Grandjean's team found that all of the five PFCs measured showed negative associations with antibody levels. In children who had twice the average levels of PFCs in their blood at age 5, their immune response to the tetanus and diphtheria vaccines at age 7 was only half of what it should have been, Grandjean said.

The researchers noted that most levels of PFCs measured in the children studied at age 5 were lower than the levels found in a group of 3-year-olds to 5-year-olds in the United States studied in 2001 and 2002.

Another children's environmental health expert said the findings were concerning. "It's one more thing, along with a number of other findings about perfluorinated chemicals, that suggests we should all be concerned about them in general and try to decrease everybody's exposure to them," said Dr. Jerome Paulson, medical director of the Child Health Advocacy Institute at Children's National Medical Center in Washington, D.C.

Grandjean said that in addition to avoiding products made with PFCs such as microwave popcorn and nonstick cookware, parents who want to reduce their young children's exposure to PFCs should vacuum their rugs and upholstery more frequently "to control the levels of house dust."

More information

The U.S. Centers for Disease Control and Prevention has more on exposure to PFCs.

TUESDAY, Jan. 24 (HealthDay News) -- After studying data on more than 3,700 pairs of identical twins, researchers from Northwestern University found that low birth weight was associated with more than triple the risk for autism spectrum disorder among twins in which autism only affected one of the children.

"That only one twin is affected by ASD [autism spectrum disorder] in some identical twin pairs suggests that environmental factors may play a role either independently or in interaction with autism risk genes," study author Molly Losh, director of Northwestern's Neurodevelopmental Disabilities Laboratory, said in a university news release.

"Our study of discordant twins -- twin pairs in which only one twin was affected by ASD -- found birth weight to be a very strong predictor of autism spectrum disorder," she added.

The study, which was released online in advance of publication in an upcoming print issue of the journal Psychological Medicine, used data from the Swedish Twin Registry's Child and Adolescent Twin Study.

In analyzing twins in which one baby was more than 14 ounces, or at least 15 percent heavier at birth than the other, the researchers found the risk for autism rose 13 percent for every 3.5 ounce drop in birth weight.

The study results suggested that birth weight could play a role in the complex causes of autism by interacting with a child's underlying genetic predisposition, or likelihood, of developing the condition, the researchers said.

Losh added that because autism is a developmental disorder involving early brain development, prenatal and perinatal environmental factors, such as birth weight, may be especially important.

The researchers noted, however, their findings may not apply to children who are not part of a multiple-birth pregnancy.

While the study found an association between birth weight and autism risk, it did not prove a cause-and-effect relationship.

More information

The U.S. National Institute of Neurological Disorders and Stroke has more about autism.