l(^(^ 



Constant 



Fig. 321 Common ragweed. How may this 

 plant harm yon? (hugh spencer) 



moderate smokers. He discovered that a 

 slightly smaller number of heavy smok- 

 ers might be expected to reach the age 

 of thirty-five than of the moderate 

 smokers and nonsmokers. The difference 

 in life expectancy is even more apparent 

 at forty, and a considerably larger num- 

 ber of nonsmokers and moderate smok- 

 ers than heavy smokers may expect to 

 reach the age of sixty. He stated his con- 

 clusions in moderate and general terms: 

 shortening of life seems to be associated 

 with the smoking of tobacco and the 

 amount of shortening increases with the 

 amount of tobacco used. He did not say 

 that moderate smoking makes people die 

 at an earlier age. Scientists are not pre- 

 pared to state just how or to what de- 

 gree the normal body is affected by con- 

 tinued but moderate smoking. 



The first effect of tobacco is to stimu- 

 late slightly. Taken in large amounts it has 

 a number of marked effects. It contains 



Care Is Needed for Health unit vi 



a substance known as nicotine. When 

 this is injected directly into the veins it 

 is a very powerful poison. Inhaling 

 fumes from a cigarette smoked to the 

 end can put into your system i to 2 mil- 

 ligrams of nicotine. The fatal dose is 60 

 to 120 milligrams. Nicotine in a certain 

 concentration in the blood causes an in- 

 crease in blood pressure, a quickening of 

 the heart beat, and an immediate drop in 

 the temperature of the finger tips. 



You probably know that people with 

 serious circulatory diseases, with aller- 

 gies, sinus trouble, or throat irritations 

 are generally advised not to smoke. Ath- 

 letes while in training may not smoke; 

 smoking seems to make them short- 

 winded. All these facts should make us 

 think twice before we allow ourselves to 

 acquire a habit which certainly cannot 

 improve our health and which may at 

 some time be injurious. It is easy to keep 

 from acquiring the habit since there is 

 never an immediate desire to smoke after 

 the first trial. 



Alcohol. It has been estimated that in 

 the United States there are at least 70 

 million people who drink alcohol. Of 

 these it is believed that there are about 

 2 million who sometimes drink to excess 

 and at least half a million who are 

 chronic alcohohcs, that is, men and 

 women who are unable to keep them- 

 selves from drinking to excess. Evidently, 

 the problem of alcohol is a very impor- 

 tant social problem. It was for this rea- 

 son that the American Association for 

 the Advancement of Science some years 

 ago appointed a Commission to study all 

 phases of the problem. The detailed find- 

 ings cannot be given here. But this much 

 seems to be clear: alcoholism often 



