How the Digestive System Works
The digestive
system processes and digests the food we eat, allowing our body to utilise the food’s
nutrients and energy. It is an essential system of the body as it stores both
water and nutrients for immediate use and as energy reserves.
Organs of the
digestive system are divided into two parts. One part is known as the
alimentary canal – or gastrointestinal tract - which is about nine metres long,
beginning at the mouth and ending at the anus. The alimentary canal consists of:
·
The mouth
·
Pharynx
·
Oesophagus
·
Stomach
·
Small intestine
·
Large intestine.
The second part is
known collectively as the accessory organs, consisting of the pancreas, liver
and gall bladder.).
·
The pancreas is approximately six inches long
and located deep in the abdomen between the stomach and the spine. It secretes
digestive enzymes into the small intestine to complete the chemical digestion
of foods. It also secretes the hormones insulin and glucagon which regulate
blood sugar.
·
The liver produces bile and secretes it into the
small intestine.
·
The gallbladder stores and recycles excess bile
from the small intestine in order for it to be reused for the digestion of
subsequent meals.
How is Food Digested?
The digestive
system begins at the mouth (oral cavity), where our teeth grind food into small
pieces which are moistened by saliva before it is swallowed. By the time the
chewed food reaches the stomach, the saliva has already started the process of
breaking down carbohydrates thanks to the enzyme salivary amylase. The stomach
contains hydrochloric acid and digestive enzymes which aid the breakdown and
digestion of food. It acts as a storage unit, allowing the body time to digest
the food sufficiently.
The next stage in
the digestive system involves the small intestine, in which 90% of all
nutrients are extracted from the food that enters it. Food then travels to the
large intestine where water is absorbed and symbiotic bacteria help to break
down waste products, allowing faecal (waste) matter to enter the rectum and be
excreted through the anus.
Keeping Your Digestive System Healthy
1. Drink
plenty of water and clear liquids such as herbal teas
Water plays a
vital role in the process of converting food into both energy and tissue.
Digestive secretions have a high water content which softens, dilutes and
liquefies the food, aiding the digestive process. It also aids peristalsis (the
wave-like movement of muscles which help you swallow and move food through the
digestive system) by lubricating the gut walls to encourage the efficient
movement of food along the gastrointestinal tract, or alimentary canal.
Different water content on each side of the intestinal tract allow for the
proper absorption of nutrients. Water also helps to soften stools which aids
elimination and helps to prevent, and ease, constipation. Not only do drinks contain water, but many foods contribute
to our intake of the water. For example, eggs are comprised of around 75% water
and fruit and vegetables’ water content ranges from 70% to 95%. One kilogram of
fruit and vegetables (around eight portions) contains up to a litre of water.
Water even comprises approximately 35% of bread.
2. . Eat
plenty of fibre
The main component of dietary fibre is derived from
cellulose. Cellulose is comprised of three or more sugar molecules bound
together and takes longer for the body to break down into glucose, providing a
slower and more sustained release of energy and keeping you fuller for longer
after a meal. Eating plenty of fibre will help to prevent constipation, however
if you suddenly increase your fibre intake from very little to lots, you will
probably notice a few side effects in the form of bloating, trapped gas and
flatulence. These symptoms will pass after a few days, once your body has
become accustomed to the new higher intake.
Fibre is found in abundance in the following foods:
- Beans
This doesn't have to mean eating baked
beans every day; try kidney beans, adzuki beans, cannellini beans or borlotti beans, there
are many more varieties to choose from. They are easy to incorporate into your
daily diet, try using them instead of mince in a shepherd’s pie or Bolognese or
add them to salads, soups and stews.
- Whole grains
Swap white bread for wholemeal, white pasta
for wholewheat and regular rice for brown rice.
- Potatoes and sweet potatoes with their skin
The potato’s skin contains the bulk of the
nutrients and fibre. Try boiling, baking or roasting with a drizzle of rapeseed or olive oil.
- Bran cereal and porridge oats
Any cereal which contains 5g of fibre per
serving counts as ‘high fibre’.
- Nuts
Choose almonds, pecans and walnuts as these
have higher fibre content than other nuts, and always choose raw, unsalted nuts.
- Fruit and vegetables
If it’s plant based, it’s fibrous. Fruit
and vegetable skins provide a great source of fibre so if possible, don’t peel
them! Green vegetables contain less starch and more fibre than the other foods
mentioned, meaning they provide less of a sugar hit. Try broccoli, spring
greens and kale.
3. Exercise
regularly
Taking regular exercise keeps your digestive system healthy
and strong by toning the muscles in your digestive tract. This means you’re
more likely to have regular bowel movements and less likely to suffer from
inefficient digestion. Acid reflux, heartburn, a bloated ‘heavy’ feeling in
your stomach, constipation and bad breath are all signs that your digestive
system is not as healthy as it could be, so by exercising you will increase the
blood flow to system while toning and building strength. Yoga is a particularly
good exercise to try if you’re suffering from uncomfortable symptoms and
constipation. Any asanas – or postures – that involve twists and forward bends
will improve blood circulation and help ease the symptoms.
No comments:
Post a Comment