Nutritional Aspects of DM Flashcards Preview

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Flashcards in Nutritional Aspects of DM Deck (13):
1

describe why weight loss is seen in patients with T1D

  • accelerated lipolysis and muscle proteolysis
    • insulin facilitates storage of triacylglycerol in adipose tissue. insulin deficiency = lipolysis
    • insulin facilitates entry of AAs into muscle and increases protein synthesis. insulin deficient = muscle proteolysis and negative nitrogen balance

2

describe basis of glycosuria and polyuria

  • hyperglycemia = more glucose being filtered through to kidney
  • large amount of glucose filtered that exceeds the reabsorptive capacity of tubule; glucose is osmotically active which results in polyuria

3

describe T2D

  • target tissues for insulin (liver, adipose, muscle) do not respond to circulating insulin (insulin resistance) and there is a decrease in insulin secretion with time (B-cell fatigue)
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4

describe the mechanism of insulin resistance

  • reduced serum levels of adiponectin impair metabolism of fats
  • elevated levels of leptin impairs insulin action
  • elevated cirucling FFAs
    • high FFAs impair action of insulin on the liver and impair insulin secretion from pancreas
  • low levels of glucagon-like peptide 1 (GLP-1) that increases insulin secretion

5

describe normal action of insulin on blood glucose

  1. insulin decreases hepatic glucose output
  2. insulin increases the uptake of glucose by adipose tissue and skeletal muscle via GLUT-4
  3. as a result of combined action on liver and extrahepatic tissues, insulin reduces the blood glucose level

6

describe mechanism of hyperglycemia in T1 and T2 diabetes

  • increased glucose production by liver
  • decreased number of GLUT-4 in peripheral tissues
  • decreased secretion of insulin from the pancreas

7

describe diabetes flowchart

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8

describe dyslipidemia

  • increased LDL
  • decreased HDL
  • increased serum triacylglycerol (increased VLDL) and reduced activity of lipoprotein lipase (insulin needed for optimal LPL activity)
  • increased circulating FFAs due to increased breakdown of TAGs in adipose tissue

9

describe laboratory tests for diagnosis of DM

  • fasting plasma glucose >126 mg/dL 
  • oral glucose tolerance test (OGTT)
    • used to evaluate ability to regulate glucose metabolism
    • used to identify patients with prediabetes and gestational diabetes
    • 2 hour plasma glucose >200 mg/dL after 75 gms of glucose

10

significance of HbA1c?

  • HbA1c is the non-enzymatic glycation of hemoglobin 
  • indicator of long term glucose levels (past 3-4 months)
  • HbA1c levels greater than 6.5% diagnostic for DM

11

describe OGTT

  • performed on an individual after an overnight fast
  • subject administered a known load of glucose (75 gm)
  • a diabetic patient has a high fasting glucose, high 2 hours glucose and a decreased tolerance to glucose

blue = normal

green = prediabetes

red = diabetic

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12

describe dietary modifications with carbohydrates

  • foods that rapidly increase plasma glucose (high glycemia indexi) should be replaced with foods with lower glycemic index
  • refined carbs (mono and disaccharide) content in the diet should be reduced and replaced by artificial sweeteners (aspartame, sugar alcohols)

13

describe dietary lipids and dietary fiber modifications

  • lipids:
    • low saturated fats
    • no trans fats
    • reduction in dietary cholesterol
    • Mediterranean diet (monounsaturated fatty acids)
    • increase omega-3
  • increase dietary fiber content