Nutrition I Flashcards
(30 cards)
Roles of nutrition at cellular level
- Provide energy
- Incorporated into cellular compounds
- Provide structural elements
- Support mechanical, chemical electrical processes
Roles of nutrients at molecular level
- Regulate gene expression
- Protect, function and support catalytic activities of enzymes
- Demonstrate hormone-like activity
- Facilitate hormone receptor binding and activity
- Support and regulate immune system activities
Importance of nutrition
- Erythropoiesis
- Cognitive development and neurological function
- Skeletal development and remodeling
- Immune response
Types of macronutrients
- Fats
- Carbohydrates
- Proteins
Roles of carbohydrates
- Important source of energy
- Provide energy to muscle
- Allows proteins to perform their function
- Enable healthy function of CNS
- Form components of other molecules eg glycolipids, glycoprotein
- Form component of nucleic acids
- Provide dietary fibre
Benefits of insoluble fibre
- Increases stool weight
- Promotes regular elimination of waste
- Prevents constipation
- Reduce risk of haemorrhoids and diverticulitis
Benefits of soluble fibre
- Food source for gut bacteria
- Fermentation of soluble fiber results in release of short chain fatty acids and B vitamins
- Short chain fatty acids block cholesterol synthesis in liver
- Reduce plasma cholesterol by enhancing hepatic conversion to bile acid
- Reduce postpandrial rise in blood glucose
- Delay gastric emptying and increase satiation
Types of soluble fibre
Pectin, gum
Types of insoluble fibre
Cellulose, hemicellulose, lignin
Dietary sources of pectin
- Apples
- Strawberries
- Citrus
Dietary sources of gum
- Oats
- Legumes
- Guar
- Barley
Dietary sources of cellulose
- Whole wheat
- Bran
- Vegetables
Dietary sources of hemicellulose
- Bran
* Whole grains
Dietary sources of lignin
- Fruits
- Edible seeds
- Mature veg
Carbohydrate RNI
CHO: 55-70% of energy
Total sugar (natural, artificial): <15%
Dietary fiber: 20-30g/day
Negative health effects of excessive CHO
- Dental caries
- Obesity
- CVDs
- Colorectal cancer
Dental caries
A-amylase, bacteria in mouth break down foods containing sugar/starch -> produce acid -> increase risk of dental caries
Colorectal cancer
Decreased intake of soluble fibre -> decreased production of SFAs (plays role in arrest of cell growth, differentiation & cell death) -> increased risk of cancer
Roles of proteins
- Growth and maintenance
- Cell structure
- Pigment protein
- Antibodies and hormones production
- Source of energy
- Maintenance of fluid balance
Dietary sources of protein
Animal sources: Fish, meat, poultry
Plant sources: Legumes, nuts
Protein RNI
10-15% of energy
Roles of fats
- Source of energy
- Supply of essential fatty acids
- Cell structure
- Required for absorption of fat soluble vitamins
- Increase palatibility
Dietary sources of fats
- Monounsaturated & polyunsaturated fats: soybean/canola/sunflower/live/palm/coconut oils, nuts
- Saturated fats: animal fats, butter, palm/coconut oils
- Trans fats: margarine, confectioneries
Fats RNI
20-30% of energy
