Nutrition and Diabetes Jamie Pope, Steven Nizielski, and Alison McCook NUTRITION for a Changing World FIRST EDITION Chapter 5 Nutrition and Diabetes Medical Miracles © 2016 by W. H. Freeman and Company & Scientific American

Chapter 5 Objectives Describe how blood glucose is regulated Explain what happens when sensitivity to insulin is impaired Explain the difference between diabetes and prediabetes List health issues that are common in people with poorly controlled diabetes Describe how gestational diabetes differs from type 1 or type 2 diabetes Describe factors that increase the risk for diabetes and those that protect against it, and understand how these factors relate to the Dietary Guidelines for Americans

Diabetes Mellitus Patients waste away to nothing It was considered a death sentence What happened in 1922 to change this?

What Is Diabetes Mellitus? Patients have a problem with regulating blood glucose (sugar) Normally blood glucose is tightly regulated

Blood Glucose Regulation Pancreas secretes insulin in response to increased blood sugar Stimulates cells to take up glucose from the blood Promotes extra glucose to fat in liver and adipose Pancreas insulin secretion increases with increased glucose concentrations in the blood; therefore, it increases after we eat. Insulin opens the channel in skeletal muscle, cardiac muscle, and adipose tissue, to take up glucose from the blood.

Blood Glucose Regulation Pancreas secretes glucagon in response to decreased blood sugar Stimulates liver to release glucose into the blood Breaks down glycogen into glucose Synthesizes new glucose

Disrupted Blood Glucose Regulation Type 1 diabetes Lack of insulin Autoimmune disease Destroys insulin-producing cells in pancreas

Type 1 Diabetes Mellitus Pancreas cannot produce insulin Muscle and adipose cannot take up glucose Body cannot use glucose Causes hyperglycemia Glucose spills into the urine Diabetes is the Greek word for “siphon” Mellitus is the Latin word “sweet”

Type 1 Diabetes Mellitus Fatty acids released from adipose tissue Used as energy source instead of muscle protein Cannot be used by the brain Converted to ketone bodies in the liver Ketoacidosis can result Diabetic ketoacidotic coma (DKA)

Treatment of Type 1 Diabetes Disease treated with insulin injections Injections discovered in 1921 by Dr. Banting who injected it into dogs First human patient was a 14-year-old boy Dr. Frederick Banting began research in dogs with his assistant Charles Best at the University of Toronto. They removed the pancreas of a dog, ground it up to disrupt the digestion function and stop it from producing digestive enzymes, filtered it, and injected it into another dog with diabetes. The dog’s blood glucose went down, and he showed no bad side effects. They went to slaughter houses to get pancreases from pigs and cows, which also worked in the dogs. A 14-year-old boy, Leonard Thompson, was admitted to Toronto General Hospital with diabetes. He weighed only sixty-five pounds and was likely to die soon. The parents gave permission in January 1922 to inject him with insulin from the research project. The boy did well, and others with diabetes began getting these injections. Dr. Banting and Dr. Macleod, the head of physiology at the University of Toronto, won the Nobel Prize for Physiology of Medicine. In 1923 a pharmaceutical company, Eli-Lilly, began making insulin for treating diabetics.

Insulin Sensitivity and Resistance

Type 2 Diabetes Risk Factors Obesity Physical inactivity Genetics Lifestyle 9 out of 10 people with diabetes have type 2 Obesity: 80% to 90% of people with type 2 diabetes are obese Genetics: if one identical twin has type 2 diabetes, the other twin will also have type 2 diabetes 75% of the time

Diagnosing Insulin Resistance Prediabetes Fasting blood glucose 100 to 125 mg/dL Oral glucose tolerance test (OGTT) 140 to 199 mg/dL Type 2 diabetes Fasting blood glucose >125 mg/dL OGTT >200 mg/dL

Diagnosing Insulin Resistance

Prediabetes Increased risk for Treatment through Type 2 diabetes Heart disease Stroke Treatment through Lifestyle strategies Weight control Physical activity Dietary modifications

Diabetes Symptoms Excessive thirst Blurred vision Weight loss

Complications of Diabetes Damage to Heart Blood vessels Kidneys Eyes Nerves

Gestational Diabetes Occurs because of high blood sugar during pregnancy Obesity increases risk Exercise reduces risk Increases complication of pregnancy Causes the baby to grow too large Creates higher risk of developing type 2 diabetes

Gestational Diabetes Pregnancy hormones cause insulin resistance Glucose crosses placenta to infant Infant produces excess insulin Extra fuel and insulin causes infant to grow

Gestational Diabetes Risk Factors Obese prior to pregnancy Older than 25 years Family history of type 2 diabetes Non-White race

Gestational Diabetes Consequences For the mother Higher incidence of cesarean section High blood pressure during pregnancy Increased risk of developing diabetes in 10 to 20 years For the infant Risk of shoulder injury during birth Higher risk of breathing problems Increased risk of becoming an obese child Increased risk of developing diabetes as an adult

Diabetes on the Rise By 2030, 550 million people worldwide expected to have diabetes Type 2 diabetes caused by Obesity Overeating Decreased physical activity Increased sedentary behaviors Type 1 diabetes used to be juvenile-onset diabetes, and type 2 was adult-onset diabetes. This is no longer the case. Children developing type 2 diabetes has increased tenfold, while there is also a rise in children developing type 1; one can no longer tell the type of diabetes by age.

Tip the Balance in Favor of Diabetes Prevention Anti-diabetes factors: Lean body and physical activity Diet rich in whole grains, beans, healthy fats, and oily fish Pro-diabetes factors: Sedentary lifestyle Overweight and obesity Diets with unhealthy fats, red and processed meats, refined grains, sugar, sweetened beverages

Type 1 Diabetes Treatment Insulin Injections Insulin pump Glucose monitoring Meter Track food choices and activity Match insulin to achieve desired blood glucose levels

Type 2 Diabetes Treatment and Prevention Lifestyle modification Changing diet Increasing physical activity Maintaining a healthy body weight If lifestyle does not help control blood glucose levels Oral medications are available Insulin injections may be required

Effect of Food on Blood Glucose Carbohydrates Resistant starches Glycemic index (GI) Glycemic load [food’s GI x food’s grams of carbohydrates]/ 100

Diet for Diabetes Count carbohydrate Monitor fat intake Determine grams of carbohydrates at each meal and snack Monitor fat intake <7% calories from saturated fat Limit trans fat Increase physical activity

Hypoglycemia Blood sugar <70 mg/dL Fasting hypoglycemia Reactive hypoglycemia Epinephrine Stimulates glucose synthesis in the liver

Summary Diabetes mellitus, more commonly known as diabetes, is a disease that disrupts the body’s ability to adequately regulate glucose metabolism Insulin and glucagon are hormones secreted by the pancreas that regulate glucose metabolism and blood glucose levels Insulin enables cells in the skeletal muscle, cardiac muscle, and adipose tissue to take up glucose from the blood. Insulin also promotes the conversion of excess glucose to glycogen in the liver and muscle. Additionally, as glycogen storage is limited, insulin stimulates the conversion of glucose to fat in the liver and adipose tissue Glucagon is responsible for increasing glucose availability in the blood when blood glucose levels fall, by signaling the liver to break down glycogen or synthesize new glucose molecules

Summary (Cont’d) Type 1 diabetes is an autoimmune disease characterized by the destruction of insulin-producing cells in the pancreas and increased levels of blood glucose (hyperglycemia) Type 2 diabetes is the most common form of diabetes and is characterized by insulin resistance and hyperglycemia Insulin resistance is a common condition in which cells lose their sensitivity to insulin, and it often precedes development of type 2 diabetes A diagnosis of diabetes is based on blood glucose concentrations of at least 126 mg/dL of blood after an 8-hour fast, and an oral glucose tolerance test result of at least 200 mg/dL 2 hours after the ingestion of 75 grams of glucose Individuals with prediabetes or glucose levels higher than normal (typically 100-125 mg/dL), but not high enough to be diagnosed with type 2 diabetes, are more likely to develop some form of diabetes and are at higher risk of heart disease and stroke

Summary (Cont’d) Diabetes affects many major organs, including the heart, blood vessels, nerves, eyes and kidneys. Controlling blood glucose levels can help prevent these complications, which can be disabling or even life-threatening Gestational diabetes is a common form of diabetes that afflicts women during pregnancy, particularly women who are overweight or obese. Most women revert to normal blood glucose levels following delivery, but they may be at increased risk of developing type 2 diabetes later in life Although type 2 diabetes is influenced by genetics, lifestyle modifications, including a diet rich in whole grains, beans, and healthy fats, along with regular physical activity and maintenance of a healthy body weight can reduce the risk or potentially reverse the disease

Summary (Cont’d) Diets that emphasize foods with resistant starch may improve insulin sensitivity, satiety, and blood glucose control Food sources of carbohydrates can have different effects on blood glucose levels. The glycemic index (GI) is a ranking of how food affects blood glucose levels relative to the effect of an equivalent amount of carbohydrates. Although the clinical relevance of using the GI is unclear, a more applicable measure may be the glycemic load (GL), which indicates the effect of typical portions of food on blood glucose Hypoglycemia, or low blood glucose levels, may result from overmedication in individuals with diabetes, in response to prolonged periods of not eating or consuming excessive amounts of alcohol, or in rare cases, from abnormalities in the way the body produces and responds to insulin