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.
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.
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