December 19, 2014 08:44 UTC

Science in the News

Why Vitamins Are Important to Good Health

Why Vitamins Are Important to Good Health
Why Vitamins Are Important to Good Health

Or download MP3 (Right-click or option-click and save link)

BOB DOUGHTY: This is SCIENCE IN THE NEWS, in VOA Special English. I’m Bob Doughty.

FAITH LAPIDUS: And I’m Faith Lapidus. This week, we tell about vitamins.

(MUSIC)

BOB DOUGHTY: Many jobs must be done with two people. One person takes the lead. The other helps. It is this cooperation that brings success.

So it is with the human body. Much of our good health depends on the cooperation between substances. When they work together, chemical reactions take place smoothly. Body systems are kept in balance.

Some of the most important helpers in the job of good health are the substances we call vitamins.

FAITH LAPIDUS: The word “vitamin” dates back to Polish scientist Casimir Funk in 1912. He was studying a substance in the hull that covers rice. This substance was believed to cure a disorder called beriberi.

Funk believed the substance belonged to a group of chemicals known as amines. He added the Latin word "vita," meaning life. So he called the substance a “vitamine” -- an amine necessary for life.

BOB DOUGHTY: Funk was not able to separate the anti-berberi substance from the rice hulls; it was later shown to be thiamine. Other studies found that not all vitamines were amines. So the name was shortened to vitamin. But Funk was correct in recognizing their importance.

Scientists have discovered 14 kinds of vitamins. They are known as vitamins A, the B group, C, D, E and K. Scientists say vitamins help to carry out chemical changes within cells. If we do not get enough of the vitamins we need in our food, we are at risk of developing a number of diseases.

FAITH LAPIDUS: This brings us back to Casimir Funk. His studies of rice were part of a long search for foods that could cure disease.

One of the first people involved in that search was James Lind of Scotland. In the 1740's, Lind was a doctor for the British Navy. He was investigating a problem that had existed in the Navy for many years.

The problem was the disease scurvy. So many sailors had scurvy that the Navy’s fighting strength was very low. The sailors were weak from bleeding inside their bodies. Even the smallest wound would not heal. Doctor Lind thought the sailors were getting sick because they failed to eat some kinds of foods when they were at sea for many months.

BOB DOUGHTY: Doctor Lind separated 12 sailors who had scurvy into two groups. He gave each group different foods to eat. One group got oranges and lemons. The other did not. The men who ate the fruit began to improve within seven days. The other men got weaker. Doctor Lind was correct. Eating citrus fruits prevents scurvy.

Other doctors looked for foods to cure the diseases rickets and pellagra. They did not yet understand that they were seeing the problem from the opposite direction. That is, it is better to eat vitamin-rich foods to prevent disease instead of eating them to cure a disease after it has developed.

(MUSIC)

FAITH LAPIDUS: Which foods should be eaten to keep us healthy? Let us look at some important vitamins for these answers.

Vitamin A helps prevent skin and other tissues from becoming dry. It is also needed to make a light-sensitive substance in the eyes. People who do not get enough vitamin A cannot see well in darkness. They may develop a condition that dries the eyes. This can result in infections and lead to blindness.

Vitamin A is found in fish liver oil. It also is in the yellow part of eggs. Sweet potatoes, carrots and other darkly colored fruits and vegetables contain substances that the body can change into vitamin A.

Why Vitamins Are Important to Good Health
Why Vitamins Are Important to Good Health

BOB DOUGHTY: Vitamin B-one is also called thiamine. Thiamine changes starchy foods into energy. It also helps the heart and nervous system work smoothly. Without it, we would be weak and would not grow. We also might develop beriberi.

Thiamine is found not just in whole grains like brown rice, but also in other foods. These include beans and peas, nuts, and meat and fish.

Another B-vitamin is niacin. It helps cells use food energy. It also prevents pellagra -- a disease that causes weakness, reddish skin and stomach problems. Niacin is found in meat, fish and green vegetables.

FAITH LAPIDUS: Vitamin B-12 is needed so folic acid can do its work. Together, they help produce red blood cells. Vitamin B-12 is found naturally in foods like eggs, meat, fish and milk products. Folic acid has been shown to prevent physical problems in babies when taken by their mothers during pregnancy.

Vitamin B-12 is found in green leafy vegetables and other foods, like legumes and citrus fruits. In some countries, it is added to products like bread.

BOB DOUGHTY: In 2003, Japanese researchers identified a new member of the B-vitamin group. It is a substance known as pyrroloquinoline quinone, or PQQ.

The researchers found that PQQ is important in the reproductive and defense systems of mice. They said the substance is similarly important for people. PQQ is found in fermented soybeans and also in parsley, green tea, green peppers and kiwi fruit.

FAITH LAPIDUS: Vitamin C is needed for strong bones and teeth, and for healthy blood passages. It also helps wounds heal quickly. The body stores little vitamin C. So we must get it every day in foods such as citrus fruits, tomatoes and uncooked cabbage.

Vitamin D increases levels of the element calcium in the blood. Calcium is needed for nerve and muscle cells to work normally. It also is needed to build strong bones.

BOB DOUGHTY: Vitamin D prevents the children’s bone disease rickets. Ultraviolet light from the sun changes a substance in the skin into vitamin D. Fish liver oil also contains vitamin D. In some countries, milk producers add vitamin D to milk so children will get enough.

Vitamin K is needed for healthy blood. It thickens the blood around a cut to stop bleeding. Bacteria in the intestines normally produce vitamin K. It can also be found in pork products, liver and in vegetables like cabbage, kale and spinach.

(MUSIC)

FAITH LAPIDUS: Experts agree that everyone needs vitamins so that their bodies can operate normally. In general, a complete diet should provide all the vitamins a body needs in their natural form. In addition, many foods and food products now have extra vitamins and minerals added.

Some people fear they do not get enough vitamins from the foods they eat. So they take products with large amounts of vitamins. They think these products, called vitamin supplements, will improve their health and protect against disease. Many adults now take vitamin supplements every day.

BOB DOUGHTY: In 2006, medical experts gathered near Washington, D.C. to discuss studies about vitamin supplements. The experts found little evidence that most supplements do anything to protect or improve health. But they noted that some do help to prevent disease.

The experts said women who wish to become mothers should take folic acid to prevent problems in their babies. And, they said vitamin D supplements and calcium can protect the bones of older women.

FAITH LAPIDUS: The medical experts agreed with doctors who say that people who know they lack a vitamin should take vitamin supplements. Some older adults, for example, may not have enough vitamin B-12. That is because, as people get older, the body loses its ability to take it from foods.

The experts also noted that taking too much of some vitamins can be harmful. They said people should be sure to discuss what vitamins they take with their doctors.

Several studies have not been able to show that taking vitamin supplements in addition to a balanced diet helps to prevent disease. One study found that older Americans do not get enough Vitamin C and required minerals. The study involved more than 6,000 individuals. More than half of them took vitamin supplements.

BOB DOUGHTY: Vitamins are important to our health. A lack of required vitamins can lead to health problems.

Different vitamins are found in different foods -- grains, vegetables and fruits, fish and meat, eggs and milk products. And even foods that contain the same vitamins may have them in different amounts. Experts say this is why it is important to eat a mixture of foods every day, to get enough of the vitamins our bodies need.

(MUSIC)

FAITH LAPIDUS: This SCIENCE IN THE NEWS program was written by Brianna Blake. I’m Faith Lapidus.

BOB DOUGHTY: And I’m Bob Doughty. Join us again next week for more news about science in Special English on the Voice of America.

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Learn with The News

  • Mideast Islamic State US

    Audio Top Islamic State Leaders Killed in Airstrikes

    Three top Islamic State leaders were killed in a series of targeted airstrikes in Iraq. U.S. not ruling out White House visit by Cuban President Raul Castro. Suspected Boko Haram gunmen kidnap over 100 women, children. Putin says Russia’s economy will improve in two years. More

  • the interview

    Video Sony Criticized for Cancelling 'The Interview'

    The company acted after a group of computer hackers attacked the company and threatened to attack movie theaters that show the film. Most people have criticized Sony’s decision to cancel the release. The US says North Korea was behind the cyber attack. North Korea denies the accusation. More

  • The MOM Incubator could save more babies in refugee camps who die due to complications of premature birth.

    Audio Low-Cost Incubator May Save More Babies

    Premature birth is the biggest killer of children worldwide. About one million babies around the world die of problems because they are born too early. Many of these babies could have been saved if they had been placed in an incubator. A young British researcher says he has found a solution. More

  • A screenshot from Cuban television shows President Raul Castro addressing the country, in Havana, Dec. 17, 2014.

    Audio US, Cuba Normalize Relations

    After the release of Alan Gross from prison, U.S. and Cuba announce policy changes that end more than 50 years of diplomatic isolation that began in the Cold War. Also in the news, India joins Pakistan in mourning after Tuesday's Taliban attack. And Sony Pictures cancels release of "The Interview." More

  • Audio How Much of You Does Facebook Own?

    If you use Facebook, your friends may have posted an update recently saying Facebook is not permitted to violate their privacy. But how much of your data -- things you post -- does Facebook legally own? Experts say Facebook's terms of service agreement clearly says they own most of what you post. More

Featured Stories

  • Video Music Shows in Private Homes Gain Popularity

    Attending a live musical performance, be it in a huge arena or a small cafe, is an exciting experience. But here in the U.S., a very different kind of performance is gaining popularity: house concerts. “There's just a totally unique experience as opposed to playing like a coffee shop or a bar." More

  • Lee Surrenders to Grant at Appomatox

    Audio Southern General Robert E. Lee Surrenders at Appomattox

    General Robert E. Lee’s military skill and intelligence helped extend the war between the states. But even his skill could not save the South from the industrial power of the North and its mighty armies -- armies that were better-fed and better-equipped. On Sunday, August 9, Lee surrendered. More

  • Uganda Playground for Disabled Children

    Audio Helping Uganda’s Disabled Children Play

    You may think that all children have freedom to play. But for children who look differently from others or have physical disabilities, the idea of play can seem far away. An organization in Uganda is seeking to change that. Read on to learn words needed to talk about this sometimes difficult topic. More

  • A microneedle used to inject glaucoma medications into the eye is shown next to a liquid drop from a conventional eye dropper. (Georgia Tech Photo: Gary Meek

    Audio Tiny Needles Treat Eye Disease

    Glaucoma is the second leading cause of blindness around the world. In the United States, more than two million people suffer from the disease. Now, researchers are developing very small needles that may offer a more effective and painless treatment for glaucoma and other eye diseases. More

  • The National Museum of Organized Crime and Law Enforcement in Las Vegas

    Audio Mob Museum Tells About the Mafia in America

    The U.S. government has long used public money to fight organized crime. Now, public money is also paying for a museum in Las Vegas to tell about "The Mob,” and not everyone is happy about that. But some say it helps the local economy by bringing people to a part of Las Vegas that few visit. More

Practice Your Writing

Confessions of an English Learner BlogConfessions of an English Learner Blog

Tell us About Our Programs