Carbohydrate Storage and Disorders By Jennifer Turley and Joan Thompson © 2013 Cengage

Presentation Overview STORAGE Blood Sugar (glucose) Starch vs. Glycogen Glycogen in detail Blood sugar regulation Insulin & Glucagon DISORDERS Lactose Intolerance & Lactose Mal-digestion Hypoglycemia Diabetes

What is Glucose Used for? Immediate carbohydrate energy &/or glycogen storage (Liver & Muscle). Brain, central nervous system (CNS), & red blood cell (RBC) function (liver glycogen). Requires a minimum of 100-150 grams carbohydrate day (continuous). Muscle functioning (muscle glycogen). Fat synthesis (excess energy intake).

What is Glycogen? Whole grain complex carbohydrates are best The storage form of glucose, “animal starch”. Made from dietary carbohydrate sources. All carbohydrate is converted to glucose then stored as glycogen or used immediately. Diets should be planned to meet the 45-65% of Calories AMDR & minimally the DRI for carbohydrate (130 gm/day for adults). Whole grain complex carbohydrates are best Carbohydrate is protein sparing

Where is Glycogen Stored? The Liver (100 grams; 400 Calories). Is used for blood sugar (glucose) regulation. The Muscle (1-4 grams/100 grams of muscle). The level increases with high carbohydrate diets & exercise. Is used for the working muscle.

How Does the Body Regulate Blood Sugar? By hormones that are produced in the pancreas. The hormones effect the liver & muscle cells. Insulin: decreases blood sugar levels. Glucagon: increases blood sugar level.

Blood Sugar Regulation

Blood Sugar Regulation

Carbohydrate Related Disorders Lactose Intolerance & Lactose Mal-digestion Hypoglycemia Diabetes

Lactose Intolerance Physiology: Lactase deficiency (completely missing in “intolerance” while low activity/levels in “mal-digestion”) is strongly tied to evolution with several gene mutations identified. Symptoms: Gas, bloating, cramps, diarrhea.

Lactose Intolerance

Dairy Products and Lactose Intolerance Use a product like lactaid Consume yogurt with live cultures Consume aged cheese OR Avoid dairy products

Allergy vs. Intolerance Lactose intolerance & mal-digestion are due to an inability to digest milk sugar (lactose) not an allergic reaction to milk protein (casein). An allergy elicits an immune reaction & involves antigens & antibodies. Antibody: Protein structures produced by immune cells that inactivate antigens (allergens). Antigen (allergen): Foreign protein substances that elicit an immune reaction. Allergic responses cause the formation of mucous in the respiratory tract, GI distress &/or hives.

Antibody and Allergen in an Allergic Immune Response

Hypoglycemia low blood sugar Reactive: Blood sugar levels drop after eating sugar. Too much insulin is secreted in response to sugar consumption. Hyperinsulinemia. Spontaneous: Liver stores of glycogen are depleted, the ability to maintain blood sugar is diminished. Happens to everyone in between meals or when food has not been consumed. 4-6 hours during the day, 10-12 hours with sleep. Drug Induced: Low blood sugar from a drug reaction. Improper insulin or oral hypoglycemic drug use with diabetes. Anti-inflammatory and thyroid medications are known to cause hypoglycemia.

Diabetes A chronic disease Is characterized by hyperglycemia (high blood sugar). Affects >20 million Americans, many unaware. Increases heart disease, stroke, kidney disease, retinopathy, and neuropathy. Decreases life expectancy. Occurs as type 1 or type 2 diabetes.

Type 1 Less common ~5% of cases Juvenile onset Is more difficult to control Insulin administration is essential in the control of blood sugar (Insulin-dependent diabetes) Is due to a genetic and/or viral factor causing auto immunity directed against the pancreatic beta cells

Physiology of Type 1 Diabetes Blood Stream Antibodies attack the insulin producing cells of the pancreas. No insulin is made. Blood glucose/sugar levels are high. Liver & muscle cells cannot take up glucose because there is no insulin to bind the cell receptor. Pancreas

Physiology of Type 1 Diabetes Insulin is injected into soft tissue & works its way into the blood stream Blood Stream 5. Insulin is injected. 6. The insulin receptor on liver and muscle cells bind to insulin & take up glucose. 7. Blood sugar levels decline. Pancreas

Type 2 Very common ~95% of cases Typically adult onset May be controlled with lifestyle changes & oral hypoglycemic agents Is caused by insulin resistance (decreased insulin receptor response) Is predisposed by obesity & genetics.

Physiology of Type 2 Diabetes 1. The pancreas produces insulin. 2. Blood glucose/sugar levels are high. 3. The insulin receptor on the liver and muscle cells are insensitive to the insulin. Blood Stream Pancreas

Physiology of Type 2 Diabetes Blood Stream 1. Oral Hypoglycemic drugs are used to make the cells respond to the insulin. 2. Blood sugar levels decline. Drug Drug pill is taken orally & works it’s way into the blood stream Pancreas

Indications of Diabetes Fasting glucose level ≥ 126 mg/dl. 2 hour post prandial (fed) blood glucose level ≥ 200 mg/dl. Hyperglycemia Normal Blood Glucose is 70-99 mg/dl Pre-Diabetes is 100-125 mg/dl

Glucose Tolerance Test Measures Carbohydrate Metabolism Normal diet for 3 days prior to test. Baseline fasting blood sugar level. (Levels ≥126 mg/dl indicate diabetes). Glucose load. 1 gm carbohydrate /Kg body weight or a max of 100 gm for adults. Monitor blood sugar every half hour for six hours.

Overweight Contributes to Hyperglycemia type 2 diabetes

Case Studies: Dick & Jane 50 100 150 200 250 300 -12 -9 -6 -3 Dick's Blood Sugar (mg/dl) Dick's Weight (lbs) months Dick’s blood sugar dropped from >600 mg/dl to 90-100 mg/dl over 12 months with weight loss from 262 to 233 lbs. Jane’s blood sugar went up from 128 mg/dl to 240 mg/dl after gaining an extra 10lbs. Over 24 months she gradually lost 100 lbs and brought her blood sugar to normal. DICK JANE

Food Composition The Glycemic Response/Index Simple sugars & foods with a high glycemic index burn up fast & elicit an insulin response. Complex carbohydrates sustain energy better.

What is the Glycemic Response/Index? The rise in blood sugar in response to food as compared to glucose. Glucose is assigned 100. The Glycemic Index of a food can be useful to anyone concerned with blood sugar control.

Glycemic Response of Foods Those with diabetes should eat foods that have a lower glycemic response or slower entrance of glucose into the blood stream. Foods with high protein, fat, & fiber lower the glycemic response.

Glycemic Index of Foods

Summary Glucose is required by the brain, RBCs & CNS for energy (ATP). Carbohydrate is the preferred energy source of the body. All carbohydrate is converted to glucose for energy. Excess carbohydrate is stored as glycogen. (liver & muscle) If glycogen stores are full, excess carbohydrate is stored as fat.

Summary Liver glycogen maintains blood sugar for brain, RBCs & CNS function. Muscle glycogen maintains the working muscle in high intensity exercise. The hormones insulin & glucagon regulate blood sugar levels. Insulin decreases while glucagon increases blood sugar.

Summary Lactose intolerance occurs when the enzyme lactase is missing. Milk allergy involves immunity. Hypoglycemia is low blood sugar. Can be reactive, spontaneous, or drug induced. Hyperglycemia is a sign of diabetes.

Summary Diabetes occurs as type 1 & type 2. Unmanaged diabetes has health implications. Individuals with diabetes should consider the glycemic response of foods for diet planning. Selecting low glycemic index foods is useful in controlling blood sugar rises. References for this presentation are the same as those for this topic found in module 3 of the textbook