Principles Of Nutrition Flashcards
Components of balanced diet
Fat Protein. Macronutrients Carbs Vitamins Minerals. Micronutrients Fibre Water
Definite nutrition and clinical nutrition
Provision of nourishment
How food influences body function
Clinical-> relationship between nutrition and disease
Define nutrient balance
Input-output=change in body stores
Buffering effect of body stores
Difference between dietary requirements and recommendations
Requirements-> amount needed to prevent disease
Recommendations-> optimum amounts
Importance of dietary fibre
Found in veg
Soluble fibre (Pectin, beta glucan)
hold water-> increase stool bulk by proliferation of bacteria
delays Gastic emptying
Prevents glucose and cholesterol absorption in small intestine-> glycocaemic response-> increased insulin
Bulking effect-> speeds colonic transport->Treat constipation-> anti cancer
Insoluble (cellulose)
Minerals
Inorganic elements that have physiological function within the body
Calcium
Adults contain 1.2 kg Needed for: Bones Cell signalling Muscle function Sources: Milk and dairy Added to flour Hard water Intestinal absorption: Calbindin Regulated by vit D
Importance of calcium
Importance:
Low plasma Ca-> stimulates PTH and vit D secretion-> activated vit D-> increased intestinal Ca absorption and regulation of Ca excretion from kidney and bone
Calcitonin-> secreted from thyroid when Ca is high-> promotes Ca excretion by kidneys and prevents bone release
Skeletal growth and calcium
Skeletal growth means Ca gain
Peaks at 18-19
Bone turnover continues breakdown and re synthesis
Peak bone mass
30 years
Higher mass= longer period of time before mass and mineral content decline to risk of fracture
Factors effecting peak bone mass
Genetic Nutrients Endocrine-> GH, sex hormones Mechanical Smoking
Iron
Needed for Haemoglobin
Absorbed as ferrous (2+) as reducing action increeases reabsorption, converted to ferric (3+)
Stores in reticulo-endothelial system (20-30%)-> liver and spleen. And bone marrow
Plasma ferritin-> major storage protein-> fe to bone marrow
Dietary sources of iron
Haem-> meat 10%
Non haem-> vegetable 90%
Absorb approximately 10% of intake
Absorption of iron, enhancers
Reducing agents Organic acids Fructose, sorbitol Alcohol Some amino acids Meat Fe deficiency Fasting Pregnancy Vit C
Absorption of iron, inhibitors
Tenins, poly phenols Phosphates, phytates Loran, lignin Proteins Ca Fe overload Alchlorhdria Ca deficiency
