GI disorders and intolerances Flashcards
How do microvilli help promote absorption of nutrients into the body?
They have a large surface area due to the circular folds of mucosa, which inreases the surface area for uptake of nutrients.
What happens when inflammation or bacteria disrupts the tight junctions at the gut barrier?
This allows harmful toxins like bacterial products and dietary antigens into the circulation.
Name some of the potential causes of GI stress during exercise
- GI ischemia (reduced blood flow to the gut)
- Reduced gastric emptying
- Reduced oesophageal peristaltic activity
- Gastric motility
- Gut damage
- Poor nutrition pre-race (highly conc CHO, fibre, PRO, dehydration)
- mechanical jostling movement of running
- upright posture
Why would a nutritionist recommend eating white bread over a McDonalds burger, fries and soda pre-event?
The McDonalds is high in fat which could take up to 6 or more hours to leave the stomach which would cause discomfort when exercising. The white bread is low fat and high carb which may onlyl take 1-2 hours to leave the stomach.
Why should you avoid hypertonic drinks?
Hypertonic food and drink contain more solutes in a solution than blood serum so your body retains water to even the osmolaity which is uncomfortable during exercise.
What is the best type of drink to consume in and around exercise and why?
Isotonic drinks as they have a similar osmolality to blood serum
Why might it be good to avoid juices high in fructose in and around exercise and consume glucose instead?
- There is slower absorption of fructose at the intestinal border
- You can burn more of the glucose you ingest as fuel compared to fructose
- Glucose is more effective at rebuilding muscle glycogen during recovery
Why are liquids better to consume than foods during exercise?
Liquids empty from the stomach faster, so it’s a good recommendation for athletes with GI stress
How might dehydration exacerbate GI symptoms?
Dehydration may increase gut permeability allowing the entry of toxins and bacteria into circulation, which can lead to inflammatory responses
When is beetroot juice recommended to consume for an athlete?
90-120mins post exercise as it increases blood flow
Why should Ibuprofen be taken after food and not on an empty stomach?
Ibuprofen reduces/inhibits COX 1 enzyme which stops prostaglandin hormone being released which is involved in gut, kidney and platelet function. This would result in side effects such as: GI problems, asthma, renal and hepatic problems, blood disorders.
Low CHO intake in an effort to reduce GI symptoms could compromise performance, so what would you recommend?
Isotonic drinks and the use of multiple transport CHO’s are recommended as they are easier and quicker to digest
Name some examples of ‘training the gut’
- Training with high volumes of fluid in the stomach–reduced bloating and fullness during exercise therefore reduced GI symptoms
- Training immediately after a meal–increase capacity to absorb CHO, increase gastric emptying and reduce bloating and fullness during exercise therefore reduced GI symptoms
What are some of the guidelines to prevent GI distress during exercise?
- Avoid high fibre foods on the day and before competition
- Avoid aspirin and NSAIDS eg. ibuprofen
- Avoid high-fructose foods
- Avoid dehydration
- Ingest CHO’s with sufficient water or drinks with lower CHO concentrations
- Practice nutrition strategies for pre-race and race-day nutrition meals to see what works
If someone had IBS what diet would you recommend?
Low FODMAP diet
If someone had Coeliac disease, Crohns disease or Ulcerative colitis what diet would you recommend?
Wheat or gluten free diets
What is IBS?
Chronic and recurring problem associated with abdominal bloating, stomach pains, constipation and diarrhoea
What may cause or trigger IBS?
- Psychological distress
- altered microbiota and gut-brain communication
- certains foods (highly individual)
What is the low FODMAP diet?
Avoiding these short chain fermentable CHO’s that are poorly absorbed in the small intestine and can aggravate GI symptoms:
Fermentable
Oligosaccharides - eg. fibre
Disaccharides - eg. lactose
Monosaccharides - eg. fructose
Polyols - eg. sweeteners (sorbitol, mannitol)
Give examples of food that a person on a low FODMAP diet should consume
Carrot, cucumber, lettuce, tomato, green beans
lactose-free milk, hard cheese
banana, orange, grapes, melon
gluten free products, oats, rice, quinoa
What recommendations would you give for someone with fructose malabsorption pre, during and post exercise?
Pre - banana and isotonic sports drink
During - water, gels, drinks or bars avoiding– fructose, fruit juice, honey
Post - gluten free pancakes with blueberries, yoghurt and nuts
What recommendations would you give someone with lactose intolerance pre, during and post exercise?
Pre - cereal with lactose free cows milk
During - water, gels, drinks or bars avoiding– anything containing lactose
Post - low fat granola with banana, nuts, cinnamon and lactose free yoghurt
Why must people with Coeliacs disease avoid gluten?
The bodys immune system attacks the gluten proteins which also destroys the villi leading to nutritional deficiencies
What would you recommend for fuelling in a athlete with coeliacs disease?
legumes, lentils, milk, rice, quinoa, fruit, potato, pumpkin, corn
