Summary
Nutrition in health and disease
Master health sciences
,Lecture 1: Rules and regulations
You should always start with a research question and then go from a broad context to specific
information. The research should be relevant and after that you can look for sponsors.
A four year nutritional intervention study costs 500.000 euros:
- Salary (research assistant, researcher, dietician, data manager, statistician.
- Equipment
- Laboratory costs
- Education
- Office equipment
- Travel costs of participants
,Lecture 2 GI Tract
Difference between digestion and absorption
Site Digestion Absorption
Mouth Carbohydrates
Lipids
Stomach Lipids
Proteins
Small bowel Duodenum Carbohydrates Most nutrients in
Lipids small amounts, but
Proteins particularly calcium
Jejunum Carbohydrates (di- Carbohydrates, amino
and tri-saccharides) acids, oligopeptides,
Proteins and lipids, vitamins other
polypeptides than B12, water
Lipids major ions and trace
elements
Ileum Any residual Most nutrients in
digestible small amounts,
macromolecules vitamin B 12 and bile
salts
Colon Breakdown of Free fatty acids
indigestible fibre by resulting from
bacterial action bacterial fermentation
Esophagus
About 30-40 cm long, function is transporting food. Muscular membrane.
Diseases of the esophagus:
- Barrett’s disease reflux damage of the lowest part of the osophagus. It can
become cancer if you don’t treat it.
- Achalasia no peristaltic movement in the esophagus, the sphincter stays closed.
Mostly fixed with surgery.
- Cancer an increase in incidence since 90’s. 2540 new patients in 2014. Five year
survival only 19%.
o Adenocarcinoma
Last part of esophagus
Mostly due to reflux and obesity
Last 20 years increased incidence
o Squamous carcinoma
In the squamous cells of the esophageal mucosa.
Mostly heavy drinkers and smokers
Another risk factor: nutrition hot drinks and a diet low in fruit and
vegetables.
o After esophagectomy stomach is partly removed.
Dumping, normally the bowel measures the amount of food. The
pancreas makes a lot of insulin in order to process the food and after
that the blood sugar drops and you become sweaty and sick.
Vagus nerve is split in half, so the pylorus isn’t able to regulate the
food drop to the bowel.
Diarrhea your bowel measures concentrated food and pulls fluids out
of the blood system, to make the food less concentrated. You get more
fluid in your bowel and that’s why there is diarrhea. If you eat a lot of
sugar this is more likely to happen.
, If all the fluids go from the blood to the bowel, your blood pressure
lowers.
Sense of hunger is less after, because of the vagus nerve is sliced
trough, that’s why people don’t experience their empty stomach.
Nutrient deficient: vitamin B11, Vitamin D, copper, calcium, vitamin B1.
Nerve system:
- Ortho-sympathetic nerve system
o T5-T12 spinal cord
o Mainly for catabolic processes. If you are, for example, running, you need this
nerve system. It breaks down the muscles and releases energy.
o Biggest nerve for GI tract for energy release is the superior mesenteric
ganglion.
o In patients with pancreatic carcinoma a blockade is made in order to block
the pain.
o Nerve cel + gliacel axons, dendrites pulses
- Parasympathetic = anabolic processes
o Vagus nerve guidance through the system and is responsible for
swallowing, coughing and a lot of other organs.
o Stimulates the bowel movement and production of digestive juices
Stomach
Function: temporary food storage, gastric juice production, kneading and mixing food with
gastric juice and gradual release of food to small intestine. Besides also production of
intrinsic factor for B12 absorption, production takes places in fundus/corpus stomach.
Food in the stomach causes stomach wall to start releasing gastrin gastrin stimulates
stomach glands to relaese the components of hydrochloric acid stomach pH reaches 1,5
acidity negative feedback acidity in the stomach causes the cells of the stomach wall
stop releasing gastrin.
Ghreline disturbed in diseases such as obesity and anorexia.
Biliary tract:
Liver
Functions: foodconversion, storage, distribution, generating biochemical units and
detoxification.
It’s red/purple, because of the blood. 1,5 liters of blood goes through the liver every minute.
Mainly two important blood structures:
- Vena porta transporting the nutrients to the liver, low in oxygen.
- Arteria hepatica brings oxygen to the liver.
There are some small veins, who can take the blood stream. At first you need to block the
other ateria.
Your liver can grow.
Bile
100 ml bile juice per 10 kg is produced by the liver. You need bile to emulsify the fats.
If you have a tumor in the bile duct, you become yellow, because of the bilirubine in the bile.
Your feces becomes kind of white, because you don’t have bilirubine in the GI tract.
Hypothesis: loss of bile in humans affects nutritional status and body weight. They always try
to keep the bile circle in tact with two tubes if necessary.
