What Control Do We Have? NONE! (WashPost article)

[Jun]

Fruit From the Family Tree

By Sally Squires
Tuesday, November 15, 2005; HE01



If you're feeling hungry as you read this, your parents may be partly to blame.

A growing number of studies find that real -- and perceived -- hunger appears to be passed down from generation to generation, just like hair color or height.

At the University of Maryland, scientists studying Old Order Amish families have pinpointed two chromosomal regions that are linked to both restrained eating and to overeating in adults. At Virginia Commonwealth University in Richmond, researchers have studied twins and also found a significant genetic link for overeating.

"Genes can really influence hunger," notes Simone Lemieux, an associate professor of nutrition and science at Laval University in Quebec City. "Some people are telling us that they are always hungry. They are right, because they have genes that are misleading them in the amount of food that they really need."

But before you use that as an excuse to let your inner appetite go wild, you should know that the latest findings suggest that genetic influences on eating behavior are bite-sized compared with environmental effects.

Scientists say there's plenty of blame to go around, from the easy availability of food to the growing tendency to engineer physical activity out of life.

"Even people who may not be genetically susceptible to overeating might overeat because of what [Yale University psychologist and author] Kelly Brownell calls the 'toxic environment,' " notes Suzanne Mazzeo, assistant professor of psychology and pediatrics at Virginia Commonwealth.

At the top of the list of environmental influences on eating behavior is something you may never have considered: your family, particularly your parents.

New research suggests that how they taught you to eat and whether they trained you to use food as a reward or comfort are among the strongest shapers of lifelong eating habits.

Published in a recent issue of Obesity Research, the findings are drawn from a 30-year ongoing study of more than 200 Quebec families, whose children had already reached young adulthood when the most recent data were collected. The study used extensive questionnaires to examine three familiar eating behaviors: dietary restraint, overconsumption of food and susceptibility to feeling hungry.

The study found that family played a significant role in shaping eating habits, especially feeling hungry and the tendency to overeat in response to both good and bad emotions, from joy and anger to boredom.

Since most of the children involved in the study were young adults, the researchers conclude that the "development of eating behaviors during growth remains a critical determinant of eating behavioral traits during adult life."

Based on the latest findings, here's how you can overcome what nature and your family served you:

Move beyond your genes . Even if you come from an overweight family that used any occasion to indulge, "you can change your environment," says Mazzeo. Ask yourself, she says, "what are your coping mechanisms with food? What is your behavior like now?"

Avoid food battles with your kids. The evidence is very clear that parents who overly restrict favorite foods "are more likely to have kids who overeat when you're not around," Mazzeo says. Provide a variety of foods, then sit back and let the kids choose what to eat.

Skip criticizing what your daughter eats. Research suggests that girls seem particularly susceptible to parental criticism about what they consume, especially when it's dished out by mothers. Why mother-daughter interactions about food are so strong and long-lasting is not well understood. Some researchers think it has to do with a tendency for girls to be more perfectionistic than boys. Studies at Penn State and other universities suggest that telling girls not to eat because they'll get fat or to stop eating are particularly damaging. "It's a tricky thing to know how to we create a good [food] environment for girls," Lemieux notes.

Sons, on the other hand, don't appear to be quite as vulnerable to food criticism. But there are only a limited number of studies on the subject. As for fathers, there's virtually no research that teases out a dad's role in shaping the eating habits of his children.

Is your hunger real? That's a tough question even for nutrition experts. "Knowing when you are really hungry can be difficult these days," notes Mazzeo. "We eat in front of the television. We eat in the car. We eat at our desks. We all do it. So it's really important to take the time to ask, 'Am I hungry right now? Am I really enjoying or even tasting what I am eating?' "

E-mail: leanplateclub@washpost.com.

© 2005 The Washington Post Company

[密斯张三]

more parent-blaminng to go


http://www.guardian.co.uk/science/story ... 87,00.html

Can't sleep? Blame your parents

Kate Ravilious
Tuesday October 11, 2005
The Guardian

If you are one of those people who drops off instantly into a deep sleep every night, then the chances are you inherited the ability from your parents. For those who toss and turn there is no hope: good sleep is encoded in the genes, say researchers.

Hans-Peter Landolt and his team at the University of Zürich compared the sleep patterns and DNA of two groups. The first contained people who find that caffeine disrupts their sleep. The second group fall asleep easily, even after a strong black coffee late at night. The difference in sensitivity to caffeine is thought to be related to our ability to process an energy-rich compound, adenosine. "Caffeine is an antagonist for adenosine sensors, blocking the binding sites and preventing people from feeling sleepy," said Dr Landolt.

By analysing DNA, Dr Landolt showed that caffeine-insensitive people have a genetic mutation which appears to make the adenosine enzyme less active. "It seems that when this enzyme is inhibited, people have more deep and intense sleep," he said.

According to Dr Landolt, about 10% of people have inherited the genetic variation from one of their parents.

The finding, which appears today in the Proceedings of the National Academy of Sciences, could help people who have trouble sleeping. "For certain sleep disorders such as insomnia it may be possible to manipulate the adenosine system and inhibit the enzyme to enable people to have more deep and intense sleep," he said.