Introduction to nutrition Flashcards
Fat soluble vitamins
AD(1,2,3)EK
Water soluble vitamins
B 1,2,3,5,6.
Folic Acid
Biotin
Vit C
Vit B1 (Thiamin Absorption) and excretion
Jejunum and ileum
Biliary and urinary
Vit B1 deficiency
Beri Beri
Wernicke-Korsakoff syndrome
Effect of thiamin on metabolic intermediates
Increased Pyruvate
Increased Lactate
Decreased Ace-CoA for TCA
Wet beri beri
High output heart failure
peripheral vaso-dilation
biventricular failure
edema
brought on by physical exertion and increased carbohydrate intake
Dry beriberi
Peripheral neuropathy of distal extremities
Both sensory and motor impariement
Occurs with little physical exertion and decreased caloric intake
Wernicke’s Encephalopathy
Confusion
Oculomotor dysfunction
Gait ataxia
Acute syndrome -treat with thiamine to prevent death
Korsakoff Syndrome
Chronic neurological condition
Impaired short term memory and confabulation
normal cognition
Roboflavin is involved in
Beta oxidation
AA oxidation
TCA cycle
Erythrocyte integrity
Conversion of tryptophan to niacin
Absence of riboflavin causes 2 Cs
Cheilosis
Corneal vascularization
Glossitis
Anemia due to red blood cell lysis
Niacin deficiency
Pellagra
Vit B6 involved in
AA metabolism
Vit B6 deficiency
Convulsions
Hyperirritability
Dermatitis
Glossitis
Excess intake of Vit B6
Sensory neuropathy that is not resolved when toxicity is corrected–was use in womens clinics in the past. ( Large doses)
Vit B12 functions
Involved in conversion of homocysteine to methionine
Rearrangement of methylmalonyl CoA to Succinyl Co-A
B12 deficiency causes (lab values)
high homocysteine and high malonyl Co-A
Folic acid deficiency causes (lab values)
High homocysteine and normal malonyl Co-A levels.
Vit B12 deficiency deficiency causes
Glossitis , posterior column findings with proprioception and vibratory sense
Slide about Cobalamin
Vit B12 digested
HCl and IF are secreted
B12 bound to R (to stabilize it) in low pH
B12, IF, R go to duodenum , R is degraded
IF bind to B12
Complex moves to ileum and bind to IF-B12 receptor on enterocytes
Complex taken up by enterocytes
IF degraded, B12 freed
B12 is bound to transcobalamin II forming TCII/B12 complex
Complex moves to basolateral side of enterocyte into circulation , stored in liver and made available for B12 dependent enzymes.
B12 deficiency
Megaloblastic anemia
Elevated MCV
Hypersegmented Neutrophils
Causes of B12 def
Pernicious anemia (body can’t use B12 properly , mostly due to absence of IF)
Diet
Surgery
Crohn’s
Pancreatic disease (can’t digest off of R binder)
Clinical signs of B12 deficiency
Neuropathy: symmetrical parenthesis and ataxia, loss of proprioception and vibration sense.
Folic acid required for
erythropoiesis
Folic acid roles
responsible for conversation of once carbon metabolism
DNA synthesis , purine metabolism , thymidylate synthase
Folic acid and enterohepatic cycle
Methylation occurs in duodenum
Absorption in jejunum, transferred to liver and excreted in bile back to the duodenum.
Signs of folic acid deficiency
Glossitis , macrocytic anemia
Causes of folate deficiency
Diet, Meds, Malabsorption, Liver dysfunction
Medications decrease absorption of dietary folate
Methotrexate , Phenytoin, Trimathoprin
Clinical symptoms of folate deficiency
Megaloblastic anemia – indistinguishable from B12 megaloblastic anemia.
Vit C absorption and regulation
small intestines and kidneys
Vit C def
Scurvy
impaired wound healing g defective tooth formation deficient osteoblast and fibroblast function swollen gums bruising anemia
Marasmus
Cachexia - seen in chronic diseases such as cancer , COPD, CHF, Anorexia Nervose, HIV/AIDS.
Kwashiorkor
Occurs mainly in setting of acute , life threatening illnesses and stress such as trauma , sepsis , ARDS, Ischemic pancreatitis
** Aggressive treatment is needed unlike in marasmus.
Diagnostics for Kwashiorkor and Marasmus
Kwashiorkor- Serum albumin less than 2.8
and at least either, edema , poor wound healing, easy hair pluckability
Marasmus - less than 3 mm tricep skin fold. Mid arm muscle circumference less than 15 cm.
Energy need equation
BEE- EE of a healthy person at rest before eating or activity .
EE=
BEE+Activty +Met Demand+ TEF
Protein estimation per day
1.2 - 1.5 grams per kg body weight
Major feeding routes
oral , peripheral vein, tube, central vein
