This is SCIENCE IN THE NEWS, in VOA Special English. I'm Shirley Griffith. And I'm Steve Ember. This week, we will present some new warnings about smoking and tobacco products.
For many years, scientists have warned us not to smoke. The World Health Organization says tobacco is the leading preventable cause of death in the world. Five million people die of causes linked to tobacco use every year.
Now, medical research has provided even more warnings. Advisers to America's Centers for Disease Control and Prevention report that pneumococcal pneumonia threatens smokers more than nonsmokers. The advisers say many smokers will need a vaccine to help prevent the disease.
This is the first time medical experts have suggested the vaccine for young and middle-aged adult smokers. The Advisory Committee on Immunization proposed that the vaccine be given to smokers ages nineteen through sixty-four.
Past research showed that cigarette smokers are four times more likely to get pneumococcal diseases than nonsmokers. For years, older adults and children under two have been urged to get the vaccine. So have people with serious health problems like diabetes and heart disease. Others at risk are people with low resistance to infection.
A C.D.C. official says it is not known why smokers are more likely to get pneumococcal infections. One idea is that smoking damages protective tissue in the back of the throat. As a result, bacteria are more likely to connect to the smoker's windpipe and lungs.
The vaccine fights several kinds of Streptococcus pneumoniae. The bacteria can infect a person's brain, causing the disease meningitis. It also can affect the blood. Experts say up to twenty percent of people with pneumococcal blood infections die, even when treated.
The experts say smoking even one cigarette a day can increase the threat of pneumococcal pneumonia by one hundred percent. The more cigarettes a person smokes, the greater the threat of the disease. Health officials say smokers should do more than get the pneumococcal vaccine. They urge people to stop smoking.
Smoking also can affect your hearing. That warning resulted from a study reported earlier this year by the International Society of Audiology Congress in Hong Kong. The study was said to be one of the largest ever carried out about hearing loss. The results were published in Springer's "Journal of the Association for Research in Audiology."
The report says hearing loss is not just a natural result of the aging process. The major cause is noise. But the report says smoking and being over-weight aid the development of hearing loss.
Four thousand eighty-three people took part in the study. They were fifty-three to sixty-seven years old. They answered questions about their medical history and their contact with possible environmental threats. They also took hearing tests.
Researchers considered the possibility of the links between the possible threats and hearing loss. The researchers found a close connection between smoking and hearing loss.
Many smokers use tobacco products while eating or drinking alcohol in public. The American state of Massachusetts banned smoking in almost all restaurants and workplaces four years ago.
Recently, a study found that the state had five hundred seventy-seven fewer heart attack deaths each year since the ban became law. The Massachusetts Department of Public Health and the Harvard School of Public Health organized the study. The findings may strengthen evidence for workplace smoking bans.
The World Health Organization says one billion three hundred million people still smoke worldwide – even after all the warnings. W.H.O. officials say eighty-four percent of all smokers live in developing countries. At the same time, smoking in the United States and Europe has decreased.
People who smoke also harm non-smokers. The American Cancer Society says this kind of secondhand smoke causes lung infections in as many as three hundred thousand young children each year.
Expectant mothers who smoke are more likely to have babies with health problems and low birth weight. Such babies may suffer health problems as they grow.
Older smokers are also at risk. A study in the publication "Neurology" showed that older adults who smoke face an increased risk of Alzheimer's disease. Decreased mental health also was more likely in persons who smoked than in non-smokers. After a time Alzheimer's, patients lose the ability to think, plan and organize.
Most people know that smoking causes lung cancer. But it also has been shown to be a major cause of cancers of the mouth, esophagus, kidney, bladder and pancreas. Cigarettes are not the only danger. Smokeless tobacco and cigars also have been linked to cancer. But these facts are not enough to prevent people from smoking.
The American Cancer Society says there is no safe way to smoke. The group has warned that smoking begins to cause damage immediately. All cigarettes can damage the body. Smoking even a few cigarettes is dangerous.
Nicotine is a substance in tobacco that gives pleasure to smokers. Nicotine is a poison. The American Cancer Society says nicotine can kill a person when taken in large amounts. It does this by stopping the muscles used for breathing.
The body grows to depend on nicotine. When a former smoker smokes a cigarette, the nicotine reaction may start again. This forces the person to keep smoking.
Studies have found that nicotine can be as difficult to resist as alcohol or the drug cocaine. So experts say it is better never to start smoking than it is to smoke with the idea of stopping later.
Experts say menthol cigarettes are no safer than other tobacco products. Menthol cigarettes produce a cool feeling in the smoker's throat.
That means that people may hold the smoke in their lungs longer than smokers of other products. As a result, scientists suspect that menthol cigarettes may be even more dangerous than other cigarettes.
Other smokers believe that cigarettes with low tar levels are safer. Tar is a substance produced when tobacco leaves are burned. It is known to cause cancer.
America's National Cancer Institute has said that people who smoke low-tar cigarettes do not reduce their risk of getting diseases linked to smoking. Scientists found no evidence of public health improvements from changes in cigarette design and production in the past fifty years.
Is there no way to smoke without harming your health?
The American Cancer Society does not think so. The group wants people to stop, or at least reduce, smoking.
For this reason it organizes the Great American Smokeout every year. The event takes place in November. Local volunteers support the efforts of individuals who want to stop smoking.
The American Cancer Society says blood pressure returns to normal twenty minutes after the last cigarette. Carbon monoxide levels in the blood return to normal after eight hours. The chance of heart attack decreases after one day. After one year, the risk of heart disease for a non-smoker is half that of a smoker.
There are products designed to help people reduce their dependence on cigarettes. Several kinds of nicotine replacement products provide small amounts of the chemical. These can help people stop smoking.
Experts also say a drug used to treat depression has helped smokers. The drug is called Zyban. It does not contain nicotine. It works by increasing levels of dopamine in the brain. Dopamine is a chemical that produces pleasure.
Here is some advice from people who have stopped smoking: Stay away from alcohol. Take a walk instead of smoking a cigarette. Avoid people who are smoking. If possible, stay away from situations that trouble you.
It is not easy to stop. And people never can completely control their own health. But as one doctor advises her patients, becoming a non-smoker is one way to gain control of your life.
This SCIENCE IN THE NEWS was written by Jerilyn Watson. Brianna Blake was our producer. I'm Steve Ember. And I'm Shirley Griffith. Read and listen to our programs at voaspecialenglish.com. Join us again next week for more news about science in Special English on the Voice of America.