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Dietary studies have suggested that people who consume large amounts of vitamin A in foods, multi vitamins, or both are more likely to suffer hip fractures than are people who ingest modest amounts.
New evidence bolsters these findings. Researchers have now correlated men’s blood concentrations of vitamin A with a later incidence of broken bones: a comparison that avoids the vagaries that plague diet-recall studies.
Taken together, the new work and the diet studies raise knotty questions about the maximum amount of vitamin A that a person can safely ingest each day, says study coauthor Karl Michasson, an orthopedic surgeon at University Hospital in Uppsala, Sweden. He and his colleagues report the new findings in Jan. 23 New England Journal of Medicine.
In the United States, the average daily intake of vitamin A through food, specially fish, eggs, and meat, is roughly 2,600 IU (international units) for men, and many multi-vitamins contain 5,000 IU. The US Institute of Medicine recommends that people get 2,300 to 3,000 IU of vitamin A each day and sets the safe upper limit around 10,000 IU.
"I believe tiffs upper level should be lowered," Michasson says. When he and his colleagues gave the men dietary questionnaires, they learned that men ingesting as little as 5,000 IU of vitamin A per day were more prone to fractures than were men getting less. Manufacturers should lower the amount of vitamin A in multi-vitamin tablets and fortified foods, such as cereals, says Michasson.
The new study began in the early 1970s when researchers stored blood samples from 2,047 men about 50 years old. Since then, 266 of the men have had at least one bone fracture. After dividing the men into five equal groups according to their blood vitamin A concentrations, the researchers found that men in the top group were nearly twice as likely as those in the middle group to have broken a bone. The correlation was particularly strong with fractures of the hip.
"I think it’s pretty conclusive now that there’s a bad effect of vitamin A supplementation," says Margo A. Denke, an endocrinologist at the University of Texas Southwestern Medical Center in Dallas. Elderly people may be at special risk because they’re slow to clear the vitamin from their bodies. Studies of animals have established that excess vitamin A stimulates the formation of cells that dissolve bone.
However, since some vitamin A is necessary to maintain good eyesight and general health, Denke and Michasson agree that fully fortified foods and supplements should remain available in countries where poor nutrition puts people at risk of a vitamin A deficiency.
A:a man taking large amounts of vitamin A will suffer hip fractures. B:the maximum of vitamin A a man takes every day should be within 3,000 IU. C:the more a man consumes vitamin A every day, the higher chance he suffers hip fracture. D:the less a man consumes vitamin A every day, the higher chance he stands of good health.
Text 2
Dietary studies have suggested that people who consume large amounts of vitamin A in foods, multi vitamins, or both are more likely to suffer hip fractures than are people who ingest modest amounts.
New evidence bolsters these findings. Researchers have now correlated men’s blood concentrations of vitamin A with a later incidence of broken bones: a comparison that avoids the vagaries that plague diet-recall studies.
Taken together, the new work and the diet studies raise knotty questions about the maximum amount of vitamin A that a person can safely ingest each day, says study coauthor Karl Michasson, an orthopedic surgeon at University Hospital in Uppsala, Sweden. He and his colleagues report the new findings in Jan. 23 New England Journal of Medicine.
In the United States, the average daily intake of vitamin A through food, specially fish, eggs, and meat, is roughly 2,600 IU (international units) for men, and many multi-vitamins contain 5,000 IU. The US Institute of Medicine recommends that people get 2,300 to 3,000 IU of vitamin A each day and sets the safe upper limit around 10,000 IU.
"I believe tiffs upper level should be lowered," Michasson says. When he and his colleagues gave the men dietary questionnaires, they learned that men ingesting as little as 5,000 IU of vitamin A per day were more prone to fractures than were men getting less. Manufacturers should lower the amount of vitamin A in multi-vitamin tablets and fortified foods, such as cereals, says Michasson.
The new study began in the early 1970s when researchers stored blood samples from 2,047 men about 50 years old. Since then, 266 of the men have had at least one bone fracture. After dividing the men into five equal groups according to their blood vitamin A concentrations, the researchers found that men in the top group were nearly twice as likely as those in the middle group to have broken a bone. The correlation was particularly strong with fractures of the hip.
"I think it’s pretty conclusive now that there’s a bad effect of vitamin A supplementation," says Margo A. Denke, an endocrinologist at the University of Texas Southwestern Medical Center in Dallas. Elderly people may be at special risk because they’re slow to clear the vitamin from their bodies. Studies of animals have established that excess vitamin A stimulates the formation of cells that dissolve bone.
However, since some vitamin A is necessary to maintain good eyesight and general health, Denke and Michasson agree that fully fortified foods and supplements should remain available in countries where poor nutrition puts people at risk of a vitamin A deficiency.
A:A．the harmful effect of vitamin B:B．vitamin A and fractures. C:C．vitamin A and human health. D:D．vitamin A deficiency.
Text 2
Dietary studies have suggested that people who consume large amounts of vitamin A in foods, multi vitamins, or both are more likely to suffer hip fractures than are people who ingest modest amounts.
New evidence bolsters these findings. Researchers have now correlated men’s blood concentrations of vitamin A with a later incidence of broken bones: a comparison that avoids the vagaries that plague diet-recall studies.
Taken together, the new work and the diet studies raise knotty questions about the maximum amount of vitamin A that a person can safely ingest each day, says study coauthor Karl Michasson, an orthopedic surgeon at University Hospital in Uppsala, Sweden. He and his colleagues report the new findings in Jan. 23 New England Journal of Medicine.
In the United States, the average daily intake of vitamin A through food, specially fish, eggs, and meat, is roughly 2,600 IU (international units) for men, and many multi-vitamins contain 5,000 IU. The US Institute of Medicine recommends that people get 2,300 to 3,000 IU of vitamin A each day and sets the safe upper limit around 10,000 IU.
"I believe tiffs upper level should be lowered," Michasson says. When he and his colleagues gave the men dietary questionnaires, they learned that men ingesting as little as 5,000 IU of vitamin A per day were more prone to fractures than were men getting less. Manufacturers should lower the amount of vitamin A in multi-vitamin tablets and fortified foods, such as cereals, says Michasson.
The new study began in the early 1970s when researchers stored blood samples from 2,047 men about 50 years old. Since then, 266 of the men have had at least one bone fracture. After dividing the men into five equal groups according to their blood vitamin A concentrations, the researchers found that men in the top group were nearly twice as likely as those in the middle group to have broken a bone. The correlation was particularly strong with fractures of the hip.
"I think it’s pretty conclusive now that there’s a bad effect of vitamin A supplementation," says Margo A. Denke, an endocrinologist at the University of Texas Southwestern Medical Center in Dallas. Elderly people may be at special risk because they’re slow to clear the vitamin from their bodies. Studies of animals have established that excess vitamin A stimulates the formation of cells that dissolve bone.
However, since some vitamin A is necessary to maintain good eyesight and general health, Denke and Michasson agree that fully fortified foods and supplements should remain available in countries where poor nutrition puts people at risk of a vitamin A deficiency.
A:lower the recommended safe upper limit of vitamin A amount. B:produce vitamin A supplement pills with less vitamin A in them. C:prevent people from eating cereals in their everyday meals. D:lower the amount of vitamin A in fortified food and supplements.
High concentration of vitamin A may lead to fracture because
A:A．elderly people are slow in digesting vitamin B:B．the absorption of excessive vitamin A makes people near-sighted. C:C．it helps produce cells that weaken the bones of human beings, D:D．vitamin A stays in human body for a long timid.
Passage Two
Protecting the heart, warding off cancer, easing the pain of arthritis -- the list of Vitamin E’s possible benefits keeps getting longer. Now, because of two new studies, some researchers say the nutrient is so critical for older people that everyone over 65 should consider taking a daily supplement.
The latest finding comes from nutrition and immunology respected: Vitamin E boosts the immune system in older people. In an eight-month study of 88 seniors, the scientists found that those taking at least 200 international units of Vitamin E daily had stronger immune responses than those taking little or none. Alzheimer’s disease. Researchers tracked 341 moderately senile patients. Those who popped 2,000 IU of Vitamin E took seven months longer to reach an advanced stage of the disease.
Rangit Kumar Chandra, a Vitamin E researcher at Memorial University of Newfoundland, Canada, says more studies are needed to learn who can benefit most and at what dose. Vitamin E thins the blood, so high doses can cause bleeding in people who also take blood thinning drags, even aspirin. Individuals with serious conditions should consult their doctors. But most people over 65, Chandra says, can take up to 200 IU with no side effects and great benefits.
A:Vitamin E Scores for Old People B:Vitamin E Fights Cancer C:You Need Vitamin E D:How to Keep Healthy
Passage Two
Protecting the heart, warding off cancer, easing the pain of arthritis -- the list of Vitamin E’s possible benefits keeps getting longer. Now, because of two new studies, some researchers say the nutrient is so critical for older people that everyone over 65 should consider taking a daily supplement.
The latest finding comes from nutrition and immunology respected: Vitamin E boosts the immune system in older people. In an eight-month study of 88 seniors, the scientists found that those taking at least 200 international units of Vitamin E daily had stronger immune responses than those taking little or none. Alzheimer’s disease. Researchers tracked 341 moderately senile patients. Those who popped 2,000 IU of Vitamin E took seven months longer to reach an advanced stage of the disease.
Rangit Kumar Chandra, a Vitamin E researcher at Memorial University of Newfoundland, Canada, says more studies are needed to learn who can benefit most and at what dose. Vitamin E thins the blood, so high doses can cause bleeding in people who also take blood thinning drags, even aspirin. Individuals with serious conditions should consult their doctors. But most people over 65, Chandra says, can take up to 200 IU with no side effects and great benefits.
A:Vitamin E's side effects B:who will gain the greatest advantages by taking Vitamin E C:Vitamin E's other benefits D:how Vitamin E cuts risks of heart attack
Passage Two
Protecting the heart, warding off cancer, easing the pain of arthritis -- the list of Vitamin E’s possible benefits keeps getting longer. Now, because of two new studies, some researchers say the nutrient is so critical for older people that everyone over 65 should consider taking a daily supplement.
The latest finding comes from nutrition and immunology respected: Vitamin E boosts the immune system in older people. In an eight-month study of 88 seniors, the scientists found that those taking at least 200 international units of Vitamin E daily had stronger immune responses than those taking little or none. Alzheimer’s disease. Researchers tracked 341 moderately senile patients. Those who popped 2,000 IU of Vitamin E took seven months longer to reach an advanced stage of the disease.
Rangit Kumar Chandra, a Vitamin E researcher at Memorial University of Newfoundland, Canada, says more studies are needed to learn who can benefit most and at what dose. Vitamin E thins the blood, so high doses can cause bleeding in people who also take blood thinning drags, even aspirin. Individuals with serious conditions should consult their doctors. But most people over 65, Chandra says, can take up to 200 IU with no side effects and great benefits.
A:People will be in perfect health if they take Vitamin E every day. B:Study showed that people who took Vitamin E regained their Flexibility. C:Vitamin E may help prevent Alzheimer's. D:Vitamin E offers a range of advantage if old people take proper dose of Vitamin E every day.
Vitamins are important to our health．Difierent vitamins are found in difierent foods．grains．vegetables and fruits，fish and meat，eggs and milk products．So which foods should be eaten to get enough of the vitamins our bodies needLet us look at some important vitamins for the answer．
Vitamin A helps prevent skin and other tissues from becoming dry．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 is also 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．
Vitamin B is also called thiamine(硫胶)．Thiamine changes starchy foods jnto 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(脚气病)．Thiamine is found not iust in whole grains like brown rice．but also jn other foods．These include beans and peas．nuts．and meat and fish．
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(铲)in the blood．Calcium is needed for nerve and muscle cells to work normally．It is also needed to build strong bones．VitaminD prevents the children’s bone disease rickets(佝偻痫)．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 f肠道)normally produce vitamin K．It can also be found in pork products．1iver and in vegetables like cabbage．kale and spinach．
______is able to change rice and wheat into energy
A:Vitamin C B:Vitamin K C:pork products D:Vitamin BI
A:Too much Vitamin D may cause skin cancer. B:Sunlight is the easiest way to get vitaminD. C:Few kinds of food naturally contain vitamin D:D. The older people need more vitamin D than the yout
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