Table Of Contentthe Common Cold
%& Improves Resistance to Infection
& Helps Combat Effects of Stress
Dt Vera iUeretem allatacteya}
Leonard Mervyn
B.Sc., Ph.D.,C.Chem.
VITAMIN CG
A clinical biochemist provides the latest information
on Vitamin C, examines its therapeutic properties
and shows how to derive most benefit from it.
By the same author:
VITAMIN E
THE B VITAMINS
VITAMIN C
Enemy of the Common Cold
by
LEONARD MERVYN
B.Sc., Ph.D., F.R.S.C.
g
NATURE'S WAY
THORSONS PUBLISHERS LIMITED
Wellingborough, Northamptonshire
First published 1981
Second Impression 1982
© LEONARD MERVYN 1981
This book ts sold subject to the condition that it shall not, by
way of trade or otherwise, be lent, re-sold, hired out, or
otherwise circulated without the publisher’s prior consent in
any form of binding or cover other than that in which i ts |
published and without a similar condition including this
condition being imposed on the subsequent purchaser. —
British Library Cataloguing in Publication Data
Mervyn, Leonard
Vitamin C.
1. Vitamin C
2. Vitamins in human nutrition
I. Title
612’.399 QP772.A8
ISBN 0-7225-0717-8
Printed and bound in Great Britain by |
Richard Clay (The Chaucer Press) Limited,
Bungay, Suffolk.
CONTENTS
Page
Introduction
Chapter
1. The Properties of Vitamin C
and Our Daily Needs 11
Vitamin C in Food 25
When We May Need More 38
What Vitamin C Does 52
Therapeutic Benefits of Vitamin C 65
wDwn Other Aspects of the Vitamin 83
Index 95
INTRODUCTION
The presence of some factor in food that prevented
and cured the dreaded disease scurvy had been sus-
pected for centuries, yet it was not until the 1750s that
citrus fruits were proved to be a rich source of this
factor. It took a further two hundred years before the
specific substance was isolated and characterized as
ascorbic acid, or vitamin C. Yet, even today, some fifty
years after its discovery, this essential vitamin still
leaves many questions unanswered.
What, for example, is the optimum intake of
vitamin C? Clinical studies have indicated the
minimum requirements to prevent scurvy, but there
could be a much higher over-all need to ensure
optimum health. The required intake could be three,
ten, twenty or even a hundred times more if various
authorities are to be believed. The simple truth is that
no one knows. The only agreement is that the U.K.
suggested minimum intake of 30mg per day is too low.
At a recent gathering of all the experts in vitamin C
research, at the University of Warwick, it was generally
accepted that this official figure needs to be increased.
Is the metabolism of Britons so different from that of
Americans and Russians that we require only one half
or one third respectively of their suggested minimum
daily intake? ;
How do vitamin C requirements vary amongst in-
dividuals? The needs for the vitamin will differ because
of genetic, environmental, lifestyle and age variations
amongst members of any population. How can we
determine who needs more than others? Should we not
aim for diets that will satisfy the vitamin C intake of
those at the upper end of the scale, be it 500mg or more
8 VITAMIN C
per day? The table in Chapter 2 shows that these
intakes are covered in good quality diets.
What happens when a person is on a long-term sub-
optimal intake of vitamin C? What are the signs and
symptoms, if any, of the conditions associated with just
sufficient ascorbic acid to prevent scurvy but not
enough to satisfy demands for optimum health? There
must be a grey area in between these two levels of
intake. Some researchers believe that a lifetime of —
barely sufficient vitamin C in the diet can lead to many
of the conditions associated with old age such as heart
disease, arthritis, arteriosclerosis, hypertension, eye
problems and perhaps even cancer. It is easy to
hypothesize on these possibilities, but far more difficult
to prove them.
How relevant is supplementary vitamin C in treating
diseases such as arthritis, viral infections like the
common cold and influenza, iron-deficiency anaemia
and some tumours? Will the vitamin in high doses
accelerate wound healing, the mending of bone
fractures and the healing of ulcers in the gastro-
intestinal tract? There is some evidence that vitamin C
may be beneficial in all these conditions, but hard facts
are still tantalizingly vague. When one group of
researchers is unable to repeat the positive results of
another group, what are the reasons? Is it dosage,
selection of patients, the protocol of the clinical trial,
varying criteria of assessing benefits, or simply the fact
that these researchers are studying the effects of just
one nutrient, vitamin C, without reference to others
that may be associated with it? -
The ultimate question, however, must be how safe
are these relatively high intakes of vitamin C? When we
look at what our fellow consumers of the vitamin, the
primates, take in their daily diets in. the wild, it is
obvious that our intakes are extremely low in com-
parison. The species who are able to make their own
vitamin C also have body levels pro rata fari n excess of
