Lecture 6C- 15 FEB. 2015 PROTEINS

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

PROTEIN ENERGY MALNUTRITION (PEM) Kwashiorkor Ghanian word Marasmus means to waste away

PEM CONTINUED KWASHIORKOR PURE PROTEIN DEFICIENCY   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

MARASMUS ENERGY DEFICIENCY All nutrients including protein low in diet   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

PROTEINS IN HEALTH-continued CANCER   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

PROTEINS IN HEALTH-continued HEART DISEASE   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

PROTEINS IN HEALTH-continued DIABETES   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

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 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

PROTEINS IN HEALTH-continued KIDNEY FAILURE Pathology- urea   High protein diet suggested by some to increase progression of kidney disease to endpoint- controversial Higher protein intake associated with increased kidney blood flow and filtration function-promotes renal failure

PROTEINS IN HEALTH-continued IMMUNE RESPONSE   IMMUNE RESPONSE Protein malnutrition -selective effects on immune cells- resulting in decreased immune function     -decreased immune maturation

PROTEINS IN HEALTH-continued IMMUNE RESPONSE continued Amino acids   IMMUNE RESPONSE continued Amino acids -arginine important for immune response -glutamine used for energy and DNA synthesis in immune response cells

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.

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.”