Colds and Age
A critical factor that plays a part in susceptibility to colds is age. A study done by the University of Michigan School of Public Health revealed particulars that seem to hold true for the general population. Infants are the most cold ridden group, averaging more than six colds in their first years. Boys have more colds than girls up to age three. After the age of three, girls are more susceptible than boys, and teenage girls average three colds a year to boys two. The general incidence of colds continues to decline into maturity. Elderly people who are in good health have as few as one or two colds annually. One exception is found among people in their twenties, especially women, who show a rise in cold infections, because people in this age group are most likely to have young children. Adults who delay having children until their thirties and forties experience the same sudden increase in cold infections. The study also found that economics plays an important role. As income increases, the frequency at which colds are reported in the family decreases. Families with the lowest income suffer about a third more colds than families at the upper end. Lower income generally forces people to live in more cramped quarters than those typically occupied by wealthier people, and crowding increases the opportunities for the cold virus to travel from person to person. Low income may also adversely influence diet. The degree to which poor nutrition affects susceptibility to colds is not yet clearly established, but an inadequate diet is suspected of lowering resistance generally.
高考英语作文复习素材 :建议信 A Letter of Suggestion
2017届高考英语一轮复习课件人教版必修三 unit2《healthy eating》
2017届高考英语一轮复习课时知能训练:人教版选修八 Unit 5《Meeting your ancestors》
2017届高考英语一轮复习课时知能训练:人教版选修八 Unit 3《Inventors and inventions》
2017届高考英语一轮复习课时知能训练:人教版选修7 Unit 5《Travelling abroad》
2017届高考英语一轮复习课时知能训练:人教版选修7 Unit 4《Sharing》
背熟这20篇范文 2017中考英语作文轻松得满分
2017届高考英语一轮复习课件人教版必修四 unit2《working the land》
2017版英语一轮精品复习学案:Unit2《The United Kingdom》(新人教版必修5)
2017届高考英语一轮复习课时知能训练:人教版选修八 Unit 1《A land of diversity》
2017届高考英语一轮复习课时知能训练:人教版选修八 Unit 4《Pygmalion》
2017届高考英语一轮复习课时知能训练:人教版选修六 Unit 4《Global warming》
2017届高考英语一轮复习课件人教版必修三 unit4《astronomy:the science of the stars》
2017届高考英语一轮复习课时知能训练:人教版必修四 Unit 1《Women of achievement》
2017届高考英语一轮复习课件人教版必修三 unit1《festivals around the world》
高考英语作文复习素材 :今天的年轻人对生活的期待作文素材
高考英语作文复习素材 :世界是如此小 The world was too small
2017届高考英语一轮复习课时知能训练:人教版选修六 Unit 5《The power of nature》
2017版英语一轮精品复习学案:Unit1《Women of achievement》(新人教版必修4)
2017版英语一轮精品复习学案:Unit4《Body language》(新人教版必修4)
2017届高考英语一轮复习课件人教版必修三 unit3《the million pound bank note》
高考英语作文复习素材 :靠打工还是家庭资助来完成学业 Earning a Degree by Working or by Family Support
2017届高考英语一轮复习课时知能训练:人教版必修三 Unit 5《Canada—The True North》
2017届高考英语一轮复习课时知能训练:人教版选修六 Unit 1《Art》
2017届高考英语一轮复习课件人教版必修三 unit5《canada—“the true north”》
2017版英语一轮精品复习学案:Unit3《A taste of English humour》(新人教版必修4)
高考英语作文复习素材 :健康的生活方式 Healthy Life Style
2017版英语一轮精品复习学案:Unit5《Theme parks》(新人教版必修4)
2017届高考英语一轮复习课时知能训练:人教版选修7 Unit 2《Robots》
2017届高考英语一轮复习课时知能训练:人教版必修五 Unit 4《Making the news》
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