Nutrition

• Macronutrients

  • Protein
  • Fats
  • Carbohydrates
• Protein

  • Source of nitrogen—amino acids
  • Growth and repair
• Essential amino acids

  • Lysine
  • Methionine
  • Valine
  • Leucine
  • Isoleucine
  • Tryptophan
  • Phenylalanine
  • Threonine
• Additional essential amino acids for children

  • Arginine
  • Histidine
  • Cysteine
  • Glycine
  • Tyrosine
  • Glutamine
  • Proline
• PEM


  Protein energy malnutrition
• Groups affected by PEM


  • Elderly
  • Surgical patients
• Effects of PEM


  • Muscle wastage
  • Poor wound healing
  • Increased risk of infection
  • Oedema
• Fats


  1 glycerol, 3 fatty acids (triglyceride)
• Types of fatty acids


  • Saturated- no double bonds
  • Unsaturated- 1 double bond
  • Polyunsaturated- 1+ double bond
• Cis form of unsaturated fatty acids


  Most common
• Trans form of unsaturated fatty acids


  Related to CHD
• Essential fatty acids


  Linoleic and alpha-linoleic acids (polyunsaturated)
• Essential fatty acids

  Used to make eicosapentanoic acid, arachidonic acid and decosahexanoic acid
• Essential fatty acids


  Precursors of prostaglandins, thromboxane, leukotrienes
• Vitamin E


  Prevents oxidation of essential fatty acids= preserves structure
• Carbohydrates


  • Monosaccharides
  • Disaccharides
  • Oligosaccharides
  • Polysaccharides
• Monosaccharides

  • Glucose
  • Fructose
  • Galactose
• Disaccharides

  • Sucrose (glucose, fructose)
  • Maltose (2 glucose)
  • Lactose (galactose, glucose)
• Oligosaccharides


  • Raffinose
  • Inulin
• Polysaccharides


  • Amylopectin
  • Amylose
  • Cellulose
• Non-starch polysaccharides (fibre)

  • Insoluble- cellulose- stimulates peristalsis
  • Soluble- slows down the reabsorption of bile acids, increases excretion of cholesterol
• Effects of Vitamin A deficiency


  • Night blindness
  • Foamy spots on eyes
  • Changes in cornea= more severe
• Vitamin A


  Toxic in high doses
• Effects of Vitamin B1 deficiency


  • Beriberi
  • Wernicke-korsakoff (alcoholism)
• Vitamin B1 deficiency


  Normally seen in fasting and persistent vomiting
• Effects of Vitamin B2 deficiency

  • Angular stomatitis
  • Itchy and watery eyes
  • Tiredness
  • Dizziness
  • Tongue papillae
• Effects of Vitamin B3 deficiency


  • Pellagra (inflamed, cracked and peeled skin)
  • 3Ds- dermatitis, diarrhoea, delirium/dementia
• Vitamin B3


  Cant absorb pure form in foods
• Effects of Vitamin B6 deficiency


  • Weak
  • Sleepy
  • Peripheral neuropathy
  • Personality changes
  • Dermatitis
  • Anaemia
  • Decreased immunity
• Effects of Vitamin B12 deficiency


  • Decreased neurological development
  • Dizzy
  • Anaemia
  • Severe encephalopathy
  • Weak in lower limbs
• Vitamin B12 deficiency


  Common in vegans
• Vitamin C


  Ascorbic acid
• Effects of Vitamin C deficiency


  • Scurvy
  • Bleeding gums
  • Tooth loss
  • Painful legs
  • Spider veins
• Effects of Vitamin D3 deficiency


  • Muscle/bone weakness
  • Ricketts
  • Increased infection risk
  • Difficulty sleeping
• Effects of Vitamin E deficiency


  • Muscle waste
• Vitamin E deficiency


  Normally when diet is poor
• Effects of Vitamin K deficiency


  • Bleeding
  • Bruising easily
  • Clotting takes longer
  • Blood in stool/urine
• Calcium


  • Difficulty swallowing
  • Faintness
  • Low BP
  • Brittle hair and nails
• Chloride


  • Fluid loss
  • Dehydration
  • Fatigue
  • Difficulty breathing
• Magnesium


  • N&V
  • Weakness
  • Decreased appetite
  • Numbness
  • Tingling
  • Muscle cramps