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.
爱情英语十句
精选英语美文阅读:爱的奇迹 Keep on Singing
美文阅读:青春物语
精美散文:爱你所做 做你所爱
态度决定一切 Attitude Is Everything
浪漫英文情书精选:To Prince Perfect献给心中的王子
精选英语美文阅读:哪有一株忘忧草? (双语)
伤感美文:人生若只如初见
精选英语美文阅读:爱他就把他留下来 (双语)
浪漫英文情书精选:Is It Love?这是爱么?
双语美文:在思考中成长
献给女性:如果生命可以重来
浪漫英文情书精选:The Best Surprise最好的惊喜
精选英语散文欣赏:爱的限度就是无限度地去爱
精选英语美文阅读:假如生活欺骗了你
精选英语散文欣赏:微笑挽救生命
精选英语美文阅读:你见或者不见我(中英对照)
浪漫英文情书精选:True Love Of My Life我的真爱
美文美诗:仙女对牧羊人的回答
精选英语散文欣赏:平等的爱
英语美文欣赏:A beautiful song
双语美文:What are you still waiting for?
浪漫英文情书精选:Starting Over Again重新来过
英文《小王子》温情语录
浪漫英文情书精选:Good Morning早上好
精美散文:守护自己的天使
浪漫英文情书精选:My Love Will Reach Any Distance爱无边
浪漫英文情书精选:My Heart And Soul我的灵魂
英语美文:A Psalm of Life 人生礼颂
精选英语散文欣赏:月亮和井
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