There's no doubt that we need vitamins to keep our bodies fit, healthy
and strong, but can we get enough of them from the food that we eat or
do we need to take supplements?
Scurvy, the disease which was
once the scourge of the
British navy, was conquered
in the 18th century by an English
doctor. He discovered that giving
the sailors lemons and limes to
supplement their diet on long
voyages could prevent the vitamin
C deficiency which gave rise to the
Lemons and limes thus became
the first vitamin supplements. Since
then, more than a dozen vitamins
have been identified that are vital
for health and more are being
discovered even today.
Now evidence is mounting that
some of these vitamins - notably A,
C and E - may have another vital
role in preventing certain types of
cancer, heart disease and cataracts.
WHAT ARE VITAMINS?
Vitamins are complex organic
substances essential in small
amounts for the normal functioning
of the body. Our bodies cannot
make most vitamins themselves so
we must get them from our diet.
Vitamins fall into two main
categories - fat soluble and water
soluble. The fat-soluble kind, which
include A, D, E and K, are absorbed
with fats into the bloodstream and
then stored in fatty tissue, mainly in
the liver. Our reserves of these vitamins may last for several years
so a daily intake is not essential. The
water-soluble vitamin C and those
from the B group can only be stored
in limited amounts, so we should
top up our stores every day.
Vitamin supplements are a range
of dietary preparations containing
one or more vitamins, sometimes combined with minerals - chemical
elements which we also need to
maintain health. They are not
intended to replace the vitamins we
get from our diet but, as their name
suggests, to supplement our diet at
times when we may not be getting
enough of certain nutrients.
THE NEED FOR EXTRA
Most doctors maintain that if you
have a well-balanced healthy diet,
there's no need for you to take
vitamin supplements. However,
many doctors of nutritional
medicine, who specialize in
treating medical problems with
nutritional supplements, disagree.
The theory does not take into
account that some people may
need more of certain vitamins if
they are in poor health or because
their lifestyle puts a heavy demand
on their vitamin reserves - heavy
drinkers, for example.
Others may need supplements
because they are fussy eaters, or
constantly dieting, or they may
cook foods in such a way that many
of its vitamins are destroyed.
Also, not everyone absorbs
vitamins from their diet efficiently.
This may lead to vague symptoms
and a feeling of being under par.
However, you can have too
much of a good thing. In large
doses, some vitamins can be harmful - particularly the fat-soluble
A and D. Too much vitamin D can
lead to kidney stones and kidney
damage in the long term, while too
much vitamin A can cause bone
and liver damage and birth defects.
Some people like to take a multi-vitamin and mineral as a 'health
insurance' for times when they
don't manage to keep to a healthy
diet, or as a kind of general tonic to build up their strength after illness
or surgery. Vitamins can also be
taken to treat certain medical
conditions; for instance there is
evidence that vitamin B6 relieves
some symptoms of PMS (pre-menstrual syndrome) while a lack
of folic acid (a type of B vitamin)
can cause a form of anaemia.
However, if you are pregnant or
trying for a baby; if you have a
medical condition; if you are taking
medicines or are at all concerned
about your health, you should
always consult your doctor before
taking vitamin supplements.
It's important to ensure that you
don't end up taking too much of one
vitamin. The vitamin content of
different products may be given in
different measurements. The
easiest way to compare products
is to look for the percentage of the
recommended daily allowance
(RDA) in each daily dose.
The RDA is a fairly arbitrary
figure based on what a healthy
person eating an 'average' diet is
estimated to need. However, some
people may need more and some
less than this to maintain optimum
health, so it is a rather misleading
term. It is due to be replaced
by estimated average requirement,
or EAR, which stresses that the
given figure is just a general rule