Premature Births, Fast Food and Dolly the Sheep
I'm Steve Ember. And I'm Phoebe Zimmerman with the VOA Special English program SCIENCE IN THE NEWS. This week, we tell about a treatment that may reduce premature births. We look at some of the legal and health issues of fast food. And, we remember Dolly the cloned sheep.
Doctors say they have discovered a way to reduce early births among women at risk of premature delivery. Normally a pregnancy is forty weeks. Babies born before thirty-seven weeks are considered premature. The treatment is a weekly injection of the hormone progesterone. Tests found that the injections lowered the rate of premature births by thirty-four percent.
Hormones are natural chemical substances found in animals and plants. Our bodies produce more than thirty of them. Organs called glands produce most of the hormones. Then blood carries them to other organs or tissue where they are used.
Doctor Paul Meis from Wake Forest University in North Carolina led the study. He called the findings the first real success against the problem of premature births. Yet the researchers are not sure how progesterone helps prevent early births.
Progesterone is normally made in the mother's ovaries. It helps support the pregnancy for the first ten to twelve weeks. Then, the baby starts to produce the hormone on its own.
Hormones are "chemical messengers." They help the body operate correctly. They control such things as growth, development and reproduction.
Scientists tested progesterone during the nineteen-sixties and seventies as a treatment to prevent premature births. But Doctor Meis says no one did a full study until now.
The research involved more than four-hundred-fifty women at nineteen medical centers around the United States. Doctors considered the women at especially high-risk because each had given birth too early before.
Not all the mothers received progesterone in the study. Most did. But, for comparison, doctors gave the others a placebo -- an inactive substance -- but did not tell them.
The injections began at sixteen to twenty weeks of pregnancy. The doctors stopped the treatments at thirty-six weeks. Doctor Meis said the researchers found the study so successful, they stopped it early. They wanted the women who got the placebo injections to receive progesterone, too.
Almost half-a-million babies are born prematurely each year in the United States alone. This is about twelve percent of all live births. And, it is the leading cause of death during the first month. Babies born too early often have lung problems or other disorders. They can have slow mental growth, hearing loss or blindness. They can also develop problems with their nervous systems.
In about half of all premature births, the cause is not known. But several things can cause women to give birth too early. Mothers who use drugs or alcohol may deliver prematurely. Older mothers and very young mothers are also at higher risk. So are women who are overweight or pregnant with more than one baby. Infections are another cause.
Doctor Meis reported on the study at a medical conference in San Francisco in early February. The findings were not yet published. The researchers now plan another study to see if they can produce even better results. This time, women will get progesterone together with omega-three fatty acids in fish. Women who do not eat enough of these fatty acids may also increase their risk of premature births.
You are listening to the VOA Special English program SCIENCE IN THE NEWS. I'm Phoebe Zimmerman with Steve Ember in Washington.
In the United States, tobacco companies have had to pay large amounts of money over diseases and deaths caused by cigarettes. Recently food companies have worried that their products could become the next big target of legal action.
Already some people have brought civil cases against McDonald's and other fast-food companies. These people say eating fast food made them fat and sick. The lawsuits charge that the companies have not warned people that this kind of food could be harmful.
America has about one-hundred-seventy-thousand fast-food restaurants that sell products high in fat and calories. These include hamburger meat sandwiches and French fries, which are potatoes deep-cooked in oil. The restaurants also serve sugary drinks.
One man charged that this kind of food damaged his health. He said he had heart attacks and developed diabetes. Several families said their children also developed the disease as they got fat on fast food. One of these teenagers weighed one-hundred-eighty kilograms.
On January twenty-second, however, a federal judge in New York dismissed the young people's case against McDonald's. Judge Robert Sweet said people cannot blame the company if they know they might gain weight or suffer health problems, but eat a lot of "supersized McDonald's products" anyway.
At the same time, though, Judge Sweet said the young people might have a better case if they could show that "the dangers of McDonald's products were not commonly well known." He called Chicken McNuggets, for example, "a McFrankenstein creation" of elements not used by the home cook.
McDonald's later released a statement in support of its McNuggets. The statement said these are made of boneless, breaded chicken cooked in vegetable oil.
Last week, the dismissed lawsuit was amended to accuse McDonald's of selling food that is more dangerous than people expect. McDonald's called the renewed action "senseless."
In any case, experts say Americans are now the fattest people in the world.
Two years ago, the government's top doctor at the time said almost sixty percent of American adults weighed too much. David Satcher also said thirteen percent of children were too fat. He said the fast-food industry, schools and government agencies should change their policies. He said extreme overweight could become the nation's leading cause of preventable death.
A private group, the Center for Science in the Public Interest, says Americans spend about half their food budgets on meals eaten outside the home. Many eating places have increased the size of their servings. And it is not easy to know the amounts of fat and nutrients in the food served in restaurants. Processed foods that are sold in food stores are required to include this information.
The food industry spends large amounts of money on advertisements to get people to buy their products.
In nineteen-ninety-eight, for example, McDonald's spent about one-thousand-million dollars on ways to increase its business. But McDonald's and Hershey Foods have also given money to an international food organization to set up a Web site to get children to exercise more.
There is debate in society over who is responsible for the current situation with weight. On one side is the argument that people have no one but themselves to blame for what and how much they eat. But others argue that the food industry is not doing enough to protect public health. These critics say the industry does not always explain what is in its products or the possible risks.
By now, you may have heard the news that Dolly the sheep is dead. She had lung disease. She was six years old, about halfway through the life of a sheep. But Dolly's body had also shown signs of aging too soon. On February fourteenth, the scientists who created her decided it was time to put her to death.
Dolly was a clone -- a genetically engineered copy of another living organism. She was not the first clone ever created, not even the first mammal ever cloned. What made her special was that she was the first mammal ever cloned from an adult cell.
Ian Wilmut and other scientists at the Roslin Institute in Scotland did not start with undeveloped cells. Instead, they took cells from a fully grown sheep and used these to create Dolly. It was not easy. Genetic engineering took a big step when Dolly was finally born in nineteen-ninety-six. But with her came new concerns about cloning.
Next week, we will present a full report about Dolly and the debate over cloning. We will also tell about the fiftieth anniversary of the discovery of the structure of D-N-A -- the genetic material that makes life possible.
Science in the News was written by Jill Moss and Jerilyn Watson. It was produced by Mario Ritter. This is Steve Ember. And this is Phoebe Zimmerman. Join us again next week for more news about science in Special English on the Voice of America.