WEDNESDAY, Nov. 4 (HealthDay News) -- Eating too fast can lead to overeating because gulping down food limits the release of hormones in the gut that trigger the feeling of being full, Greek researchers have found.

For the study, volunteers ate 300 milliliters of ice cream at different rates. Blood levels of glucose, insulin, lipids and gut hormones were measured before and after consumption of the ice cream. Participants who took 30 minutes to finish the ice cream had higher concentrations of the gut hormones peptide YY and glucagon-like peptide and also tended to feel more full than those who took less time to eat the ice cream.

Previous research has shown that the release of these hormones after a meal tells the brain the person is full, but this is the first study to examine how different rates of eating affect the release of the hormones.

"Most of us have heard that eating fast can lead to food overconsumption and obesity, and in fact some observational studies have supported this notion," lead author Dr. Alexander Kokkinos, of Laiko General Hospital in Athens, said in a news release from the Endocrine Society. "Our study provides a possible explanation for the relationship between speed eating and overeating by showing that the rate at which someone eats may impact the release of gut hormones that signal the brain to stop eating."

The study findings were released online Nov. 4 in advance of publication in an upcoming print issue of the Journal of Clinical Endocrinology & Metabolism.

More information

The U.S. National Institute of Diabetes and Digestive and Kidney Diseases has more about food portions.

TUESDAY, Nov. 3 (HealthDay News) -- If you want to lose weight, exercise and diet are crucial. But a new study says other factors appear to play a role, too -- including the number of TVs in your house and the presence of exercise equipment.

"The home environment really came out as a stronger factor than we would have anticipated," Suzanne Phelan, assistant professor of kinesiology at California Polytechnic State University and lead author of the new study, said in a news release.

Phelan and colleagues looked at the results of surveys of 167 people who lost a big chunk of their body weight -- at least 10 percent -- and managed to keep the pounds at bay for five or more years. The researchers compared this group to two other groups of people who were overweight or obese.

The researchers investigated what set the weight-losers apart from the others, and published their findings in the October issue of the Annals of Behavioral Medicine.

Those who lost weight and kept it off were about three to four times more likely to exercise than those who were obese or overweight. They were also about 1.4 to 1.6 times more likely to spend time thinking about restraining their food intake, considering things like calories.

Those who lost weight had fewer televisions in their home and less high-fat food on hand. They also had more exercise equipment in their homes, the study authors noted.

"You have to pay attention to your home environment if you want to succeed," Phelan said. "Do you have TVs in every room? When you walk into your kitchen, do you see high-fat food or healthy food?"

Dr. David Katz, director of Yale University School of Medicine's Prevention Research Center, noted in the news release that the study's findings were "common sense" and "close to self-evident."

"If you want to choose better foods, keep better foods within reach. Don't just rely on willpower. If you want to be more active, create opportunities for exercise that are always within reach. Don't just rely on motivation," he said.

More information

Learn more about obesity from the U.S. Centers for Disease Control and Prevention.

MONDAY, Nov. 2 (HealthDay News) -- At some point, nearly half of all American children and teens will live in a home that receives food stamps, a new study shows.

Researchers analyzed 30 years (1968 to 1997) of national data collected by the Panel Study of Income Dynamics and found that by the time they were 1 year old, 12.1 percent of U.S. children had lived in households receiving food stamps. That increased to 26.1 percent at 5 years of age; 35.9 percent at 10 years; 43.6 percent by age 15, and 49.2 percent by age 20.

The study also found that by age 20, about one-third of children had lived in households that received food stamps for two or more years, 28.1 percent for three or more years, 26.4 percent for four or more years, and 22.8 percent for five or more years.

Food stamp use was most likely among households with black children and those who lived in households headed by adults who were unmarried or had had less than 12 years of education, the researchers reported in the November issue of the journal Archives of Pediatrics & Adolescent Medicine.

"American children are at a high risk of encountering a spell during which their families are in poverty and food insecurity as indicated through their use of food stamps. Such events have the potential to seriously jeopardize a child's overall health," wrote Mark R. Rank, of the George Warren Brown School of Social Work at Washington University, St. Louis, and Thomas A. Hirschl, of Cornell University.

Studies have "repeatedly demonstrated that two of the most detrimental economic conditions affecting a child's health are poverty and food insecurity," the researchers noted.

"Understanding the degree to which American children are exposed to the risks of poverty and food insecurity across the length of childhood would appear to be an essential component of pediatric knowledge, particularly in light of the growing emphasis on the importance of community pediatrics," the study authors added.

More information

The U.S. Centers for Disease Control and Prevention has more about youth and nutrition.

THURSDAY, Oct. 29 (HealthDay News) -- Want to improve that osteoarthritis in your knee? New research suggests that regular Tai Chi exercise can reduce pain and help your knee function better.

"Tai Chi is a mind-body approach that appears to be an applicable treatment for older adults with knee osteoarthritis," Dr. Chenchen Wang, co-author of a study published in the November issue of Arthritis Care & Research, said in a news release from the journal's publisher.

In the United States, an estimated 4.3 million adults over 60 suffer from this form of arthritis. As many as half of American adults may develop symptoms by age 85, the U.S. Centers for Disease Control and Prevention reported recently.

Wang and colleagues from Tufts University School of Medicine recruited 40 patients, with an average age of 65, who had been diagnosed with knee osteoarthritis.

Half of the group took part in Yang-style Tai Chi sessions for an hour at a time, twice weekly over a period of three months. The Tai Chi session consisted of 10-minutes of self-message and review, a half hour of movement, 10 minutes of breathing exercises and 10 minutes of relaxing.

The other participants took two 60-minute classes per week for three months and learned about issues such as diet and nutrition, and treatments for osteoarthritis. They also stretched for 20 minutes.

Those who practiced Tai Chi had significantly less knee pain than the other group and also reported less depression, more physical function and better overall health.

"Our observations emphasize a need to further evaluate the biologic mechanisms and approaches of Tai Chi to extend its benefits to a broader population," Wang said.

More information

Learn more about osteoarthritis from the Arthritis Foundation  .