Transcript Lecture 6c powerpoint

Lecture 6C- 16 OCT. 2015
PROTEINS
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DIETARY INTAKE
RECOMMENDATIONS
DRI -0.8 grams of protein per kg body weight/day
healthy adults (19 and up)
-10-35 percent of daily calories from protein
-compare to 45-65 % from carbohydrate
-compare to 20-35 % from fat
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PROTEIN ENERGY MALNUTRITION (PEM)
p.196-199
Kwashiorkor
Ghanian word
Marasmus
means to waste away
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PEM CONTINUED
KWASHIORKOR
PURE PROTEIN DEFICIENCY
-world wide –affects all ages
-swollen liver and hence belly
-LOW protein-HIGH fibre diet
-adequate energy intake
-growth/immune issues
-nutrient absorption
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MARASMUS
ENERGY DEFICIENCY
All nutrients including protein low in diet
Wasting-use of fat stores
Growth issues-brain growth in first year
potential for reduced intelligence and
learning disabilities
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PROTEINS IN HEALTH-continued
CANCER
animal studies- initially believed to be soy protein that
inhibited breast cancer but this turned out to be false
- actually isoflavones doing the job
- one isoflavone binds to estrogen receptor reducing
impact of estrogen
-estrogen (hormone replacement) has been
linked to breast cancer
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PROTEINS IN HEALTH-continued
HEART DISEASE
-increased dietary protein and reduced dietary fat
-generally decreases blood cholesterol levels
-however animal protein tends to raise blood
cholesterol while plant protein tends
to decrease blood cholesterol
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PROTEINS IN HEALTH-continued
DIABETES
10-15 % caloric intake as protein- appropriate
diabetics tend to consume more protein than non-diabetics
- this can lead to kidney disease
soy protein and other plant proteins improve kidney
function in diabetic kidney disease compared to
animal proteins
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PROTEINS IN HEALTH-continued
OSTEOPOROSIS
Pathology-loss of bone mass
In west, very high protein intake beyond
recommended levels -this results in increased
urinary calcium output
Over a wide range of protein intakes for every 1 g
increase in dietary protein get 1 mg increase in
urinary calcium output
So get higher levels of osteoporosis even with
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good calcium intakes
PROTEINS IN HEALTH-continued
BLOOD PRESSURE
Intervention studies show no relation with dietary amount
or type
But individual amino acids like tryptophan or tyrosine
decrease blood pressure in animals due to increases in
blood pressure dropping neurotransmitters
Arginine-may drop blood pressure due to blood vessel
relaxation
Also issue of reducing fat intake
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PROTEINS IN HEALTH-continued
KIDNEY FAILURE
Pathology- urea
High protein diet suggested by some to increase
progression of kidney disease to endpointcontroversial
Higher protein intake associated with increased
kidney blood flow and filtration functionpromotes renal failure
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PROTEINS IN HEALTH-continued
IMMUNE RESPONSE
Protein malnutrition
-selective effects on immune cells- resulting in
decreased immune function
-decreased immune maturation
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PROTEINS IN HEALTH-continued
IMMUNE RESPONSE continued
Amino acids
-arginine important for immune response
-glutamine used for energy and DNA
synthesis in immune response cells
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Athletes and protein supplements
Just eat more to meet increase energy needs and will
get more protein in diet to meet increased demands on
protein metabolism
Whey protein and other amino acid/protein
supplements are a waste of time and money for
athletes and anybody else- supplements are expensive
-cheaper to get protein in a good diet.
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WHAT IS NEW IN PROTEIN
NUTRITION RESEARCH?
Gougeon R. Insulin resistance of protein metabolism in
type 2 diabetes and impact on dietary needs: a review.
Canadian Journal of Diabetes 2013 Apr;37(2):115-20.
“the challenge remains to define the optimal protein
intake and exercise regimen to protect from losses of
muscle mass and strength while maintaining adequate
glucose control in type 2 diabetes.”
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