46.Much of our good health depends on the cooperation between substances(物質).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. Vitamin A is needed to produce a light-sensitive(敏感的) substance in the eyes.People who do not get enough vitamin A cannot see well in the dark.The best source of vitamin A is fish liver oil.It is also found in the yellow part of eggs.In addition,squash(南瓜),sweet potatoes,carrots and other darkly colored fruits and vegetables contain substances that the body can change into vitamin A. Vitamin B-1 is also called thiamine.It changes starchy (含淀粉的) foods into energy.It also helps the heart and nervous system work smoothly.Without it,we would be weak and would not grow.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. Vitamin B-12 is needed so folic acid can do its work.Together,they help produce red blood cells.Without them,a person suffers from anemia (貧血癥).Vitamin B-12 is found naturally in foods such as eggs,meat,fish and milk products. Vitamin C is necessary for strong bones and teeth,and for healthy blood vessels.It also helps wounds heal quickly.The body stores very little vitamin C.So we must get it every day in foods such as citrus fruits,tomatoes and uncooked cabbage. Vitamins
(78)
of vitamin
Functions
Problems caused by(79)
of it
(80)
Vitamin A
Helping prevent poor(81)
at night
Inability to see well at night
Fish liver oil,yellow part of eggs,darkly colored fruits and vegetables
Vitamin B-1
(82)
starchy foods into energy; Being good for the (83)
work of the heart and nervous system
(84)
health and slow growth
Whole grains,beans,peas,nuts,meat and fish
Vitamin B-12
Helping prevent a(85)
disease called anemia
Anemia
Foods like eggs,meat,fish and milkproducts (86)
in it
Vitamin C
A (87)
for strong bones and teeth and healthy blood vessels