时间:2018-12-15 作者:英语课 分类:VOA慢速英语2009年(九)月


英语课

This is the VOA Special English Health Report.


Vitamin D helps bones and muscles grow strong and healthy. Low levels of vitamin D can lead to problems like rickets 1 and osteoporosis. Rickets is a deformity mainly found in children. Osteoporosis is the thinning of bone, a common problem as people, especially women, get older.


Studies in recent years have suggested that vitamin D may also have other uses. Studies have shown that low levels of D may increase the risk of heart attacks in men and deaths from some cancers. Other studies have shown that people with rheumatic diseases often have low levels of D.


The easiest way to get vitamin D is from sunlight. The ultraviolet rays react with skin cells to produce the vitamin. But many people worry about skin cancer and skin damage from the sun.


Also, darker skinned people produce less vitamin D than lighter 2 skinned people. Production also decreases in older people and those living in northern areas that get less sunlight.


Not many foods naturally contain vitamin D. Foods with high levels include oily fish such as salmon 3, tuna and mackerel, and fish liver oils. Boston University researchers reported in two thousand seven that farmed salmon had a lot less vitamin D than wild salmon.


Small amounts of D are found in beef liver, cheese and egg yolks. And some people take dietary supplements containing the vitamin. But most of the D in the American diet comes from foods like milk with the vitamin added.


These days, more doctors are testing for vitamin D levels in their patients. But as research continues, some experts worry that if people take too much D, it might act as a poison. Also, skin doctors warn people to be careful with sun exposure.


How much vitamin D does a healthy person need? Nutrition experts who advise the American government set the current recommendations in nineteen ninety-seven. The daily amount is two hundred international units from birth through age fifty. Then it rises to four hundred I.U.s through age seventy, and six hundred for those seventy-one and older. But some groups say these amounts are not high enough.


The nutrition experts are taking another look at how much vitamin D and calcium 4 people should get. The Institute of Medicine of the National Academies expects to release a report by this coming May.


And that's the VOA Special English Health Report, written by Caty Weaver 5. I'm Bob Doughty 6.



1 rickets
n.软骨病,佝偻病,驼背
  • A diet deficient in vitamin D may cause the disease rickets.缺少维生素D的饮食可能导致软骨病。
  • It also appears to do more than just protect against rickets.除了防止软骨病,它还有更多的功能。
2 lighter
n.打火机,点火器;驳船;v.用驳船运送;light的比较级
  • The portrait was touched up so as to make it lighter.这张画经过润色,色调明朗了一些。
  • The lighter works off the car battery.引燃器利用汽车蓄电池打火。
3 salmon
n.鲑,大马哈鱼,橙红色的
  • We saw a salmon jumping in the waterfall there.我们看见一条大马哈鱼在那边瀑布中跳跃。
  • Do you have any fresh salmon in at the moment?现在有新鲜大马哈鱼卖吗?
4 calcium
n.钙(化学符号Ca)
  • We need calcium to make bones.我们需要钙来壮骨。
  • Calcium is found most abundantly in milk.奶含钙最丰富。
5 weaver
n.织布工;编织者
  • She was a fast weaver and the cloth was very good.她织布织得很快,而且布的质量很好。
  • The eager weaver did not notice my confusion.热心的纺织工人没有注意到我的狼狈相。
6 doughty
adj.勇猛的,坚强的
  • Most of successful men have the characteristics of contumacy and doughty.绝大多数成功人士都有共同的特质:脾气倔强,性格刚强。
  • The doughty old man battled his illness with fierce determination.坚强的老人用巨大毅力与疾病作斗争。
学英语单词
abacinating
accuracy control
angiotensins
apical placentations
batidaceaes
Baygora
bell-curve
bellite
birdlore
blood tankage
butterbird
cable strand
caravanseraiss
card No. of the user
casenote
child record
clothes don't make the man
CMHCsA
compound mode of sprinkler arrangement
Coryphaenidae
course of fermentation
crispening current
cryptocercids
cuvier c.
Czaplinek
deaken
deformation limit
desordre
determination test
diffusion stasis
disaster-preparedness
double word boundary
earp
eczema stasis
effective lens aperture
enter the scene
equivalent input offset voltage
Ershui Township
establishing-clause
federative database
figure-8 configuration
fire-gilding
foreign body in nose
fresh surface
fucosan
G-tolerance
gets going
gosh darn
heartbond
heterotypical
hierarchical menus
high-strength wire
higher cognitive process
Hluhluwe
hydraw
initial photo interpretation report
interhuman
intradural abscess
Karlsena, Mys
Karman constant
link, digital microwave
lot-tree
luneburg
Mad as a badger
Marquis de Lafayette
molecular tie
momentum principle
mureinlipoprotein
nineteenth century
no better than
non-belief
not do things by halves
Parabrachylaema
penninoes
pirouette
plain stem
play a lone hand
preprint
puccinia caricis-baccantis
pyth
radio-noise burst
rag-roll
rapid access storage
re-sized
saint-cloud
schottky source/drain
schusky
Stroh violin
suppressing agent
swell-shrink characteristics
treasurer's department
turning rule
Uber Micro
unfaiths
unwound core
Vaas
vaginal process of peritoneum
village fair trade
writing pencil
yellow fat cell
Yondon
zaleski