VITAMINES. 
vital for the well-being of the body, but to the removal of something 
that “was necessary to neutralize the otherwise deleterious effect of a 
diet over-rich in starch.” 
The year 1906 marks a turning-point, or perhaps one should say 
starting-point, in the study of vitamines, for it was then that Professor 
Gowland Hopkins took up the scientific study of the subject. It is 
quite clear that Gowland Hopkins brought a different mental attitude 
to bear upon deficient diets than did the earlier investigators, for in 
1906 he wrote: “ In diseases such as rickets, and particularly in scurvy, 
we have had for long years knowledge of a dietetic factor; but though 
we knew how to benefit these conditions empirically, the real errors in 
the diet are to this day obscure. They are, however, certainly of the 
kind which comprises these minimal qualitative factors that I am con- 
sidering. Scurvy and rickets are conditions so severe that they force 
themselves upon our attention, but many other nutritive errors affect 
the health of individuals to a degree most important to themselves, and 
some of them depend upon unsuspected dietetic factors.” His later 
work has been described as undoubtedly marking “ the beginning of a 
full appreciation of the importance of what Hopkins has termed the 
accessory factors of the diet.” 
Following Hopkins’ pioneer work there soon accumulated an ever- 
increasing knowledge of the so-called vitamines, so that at the present 
time three distinct substances have been identified by their physio- 
logical action. Though their chemical nature is yet unknown, know- 
ledge of their function has passed the elementary stage, and from the 
qualitative into the quantitative. ‘Their location and general distribu- 
tion in plant and animal tissues have been and still are being studied, 
so that plants have now acquired another value in accordance with 
the presence or absence of any of these factors. 
There are some specially outstanding features in connexion with 
vitamines. The small amount normally ingested is out of all propor- 
tion to their physiological importance; thus 1 gramme of raw cabbage 
or 2.5 c.c. of raw swede juice given to a guinea-pig daily will prevent 
the appearance of scurvy. 
They are present in natural foodstuffs as “ instinctively consumed 
by men and animals.” It is believed that they are only formed in the 
tissues of plants, that no animal body can synthesise them, but being 
taken into the body of herbivores, they are thus available to carnivores. 
Nursing mothers denied a sufficiency of the right sort of vitamines fail 
to secrete them in the milk, and thus the sucking offspring fail to get 
adequate nutriment. ‘They are present only in certain plants and 
tissues and in certain parts of the tissues, so that the artificial prepara- 
tion of natural food may, and sometimes does, so impoverish it that 
it is no longer a “food” in the true sense of the word. 
The three accessory (essential is more descriptive thai accessory) 
food factors which up to the present have been differentiated are :— 
(1) An anti-neuritic or anti-beri-beri factor, the “ water- 
soluble B” growth factor of McCollum and his co- 
workers. shia - 
(2) An anti-rachitic or “fat-soluble A” growth factor. 
(3) An anti-seorbutie factor. + pont Nt sak 
The anti-neuritie vitamine prevents bevi-beri in man, or its analo- 
gous disease in birds, avian polyneuritis. It is necessary for the 
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