For anybody desiring to improve their body's performances,
nutrition and a balanced diet is the key. Here is a list of the
principal substances and what happens to them, including a couple of diet
tips.
- carbohydrate (sugar and starch)
- This is cut up into glucose which is then put into the blood stream
; the body tries to maintain a constant level of glucose in the blood
stream (sugar count) and all excess glucose is stored in the liver as
glycogen (if there is not enough room, the rest may be turned into
fat). The liver then releases glucose into the blood as and when you
need it. Some glycogen is also stored in the muscle cells. Glucose
is transformed into energy in your cells (mostly muscular ones), the
residue being carbon dioxide and water. What happens within the
cell will be explored in greater detail later on, as it is of capital
importance to getting fit.
Carbohydrate will not make you fat (unless you
eat too much). Carbohydrate comes in two major forms : those that taste
sugary (sugar, fruit, honey) and the foods which "fill you up"
(bread, pasta, cereals, potatoes). In the body, carbohydrate can be
rated according to how quickly it is digested and makes it into the
blood stream. This is not easily predictable, but a rule of thumb
is that processed foods (like honey, corn-flakes, mashed potatoes,
white bread) make it quicker into the blood stream than fiber-rich
food (like whole-wheat, bread, fruit, birchermuesli, pasta) and,
surprisingly enough, plain sugar. Eating the slower type will keep
you going longer and prevent you from feeling hungry. Eating the
faster type (like a chocolate bar) on the grounds that you need an
energy booster is a often a fallacy.
Because the carbohydrate metabolism is quite fast, carbohydrates are
the prime source of energy : they provide 4calories/g.
- protein
- Protein is decomposed into amino acids which are used as building
blocks to make and repair more cells. It is mostly found in meat and
fish, but for vegans and vegetarians it is luckily also to be
found in eggs, cheese and several vegetables. You should be careful
to vary your protein sources, as there are 9 amino acids which the
body cannot produce on it's own and there are no foods in which they
are all found in sufficient quantities (the only single source containing all nine is mother's milk; another advantage of breast-feeding).
The protein metabolism is rather slow ; so although protein can
provide 4calories/g, it is not much point expecting to use protein as
a source of energy.
- fat
- Fat accomplishes many small indispensable tasks in the body :
mostly when it comes to absorbing nutrients that are not soluble in
water. It gets stored in adipose cells whence it can be sent to
other parts of the body if it is needed. It often is not, so fat
will make you fat. Some types of fats do not go
to the fatty cells as they should, but rather clog up the
arteries and can lead to heart disease.
There is probably a fair amount of fat in your favorite food :
biscuits, chocolate, ice-cream, crisps, peanuts etc. this is because we
like the mouth-feel of fat. So if you enjoy some particular food (or
some brand over another) it is possibly due to the larger amount of fat
that it contains. There will still be plenty of fat left in
your diet if you cut out all the cream cakes and buns.
The fat metabolism is very slow, so fat's 9calories/g usually
become available when you are asleep ; the body just says "huh, don't
need all that, put it all in the fat-cells in case we need it some
other time". There is some research being done and it appears that
there may exist a type of quickly-digestible fat which could be of use in sport
nutrition.
- water
- H2O serves three main purposes in the body : it keeps you
cool ; it carries all the nutrients round the body (in the
blood-stream) ; it gets rid of all the waste toxins. In water,
there are always some dissolved minerals ; the liquid in our cells
also contain some. Because of the nature of the cell walls, a chemical
effect called osmosis keeps the mineral-water proportions the same
inside and outside the cell through water transfer. To make your body
feel more comfortable, it can be good to drink isotonic drinks
such as isostar or gatorade who's mineral proportions are similar to
those of your body ; this will prevent the body from having to do extra
work to get the proportions right in the blood. This is important in order to be able to absorb liquid as quickly as possible.
These are the principal macro-nutrients. It is a fairly safe bet that,
unless you are already watching what you eat, you are eating too much and
in the wrong proportions : too much fat, too much protein and too little
carbohydrate. You probably don't drink enough : you should drink at least 2
liters a day ; and try to cut out some of the caffeine, alcohol and sugar in
your drinks.
If you're starting to exercise, add even more water. Add carbohydrate (and
make sure you compensate by reducing on fat). Protein will help if you get
muscular pains, but be careful! Most protein-foods will be full of
fat.
There are many micro-nutrients that are also essential but because
there are so many of them, the best way to get them all is to
vary your foods as much as possible - and include some fresh
vegetables.