Obesity and Type 2 Diabetes

• Diet Related Disorders

  Over-nutrition 

  • Obesity (kJ)
  • Cardiovascular diseases (saturated fat)
  • Hypertension (salt)
  • Diabetes mellitus (Type II Diabetes) (sugar)

  Under-nutrition (will cover this later)

  • Anaemia (iron)
  • Osteoporosis (calcium)
  • Diverticular disease (fibre)
• What is Obesity

  • Obesity and being overweight are defined as abnormal or excessive fat accumulation that presents risk to an individual’s health.
  • Body Mass Index (BMI) is one diagnostic tool (there are many, refer to 2.1) used to assess an individual’s weight category
  • A person with a BMI of:
  • 25 or more is overweight 
  • 35 or more is morbidly obese. 
  • 30 or more is generally considered obese
• Most prevalent symptom experienced by individuals is visible fat accumulation

  Fat can be stored in different areas around the body: 

  • Android shape fat will be stored around the abdominal region (generally male)
  • Greater amount of visceral fat (fat around organs)
  • Gynoid shape, excess fat is deposited around the hip and thigh regions of the body (generally women)
  • Greater amount of subcutaneous fat (fat under skin)

  Other symptoms of an individual being obese are fatigue, joint pain, shortness of breath
• Dietary risk factors: Energy intake exceeds energy expenditure

  • The most significant cause of obesity is if an individual has a positive energy balance over a long period of time
  • Energy intake > energy expended
  •  Excess energy is stored in the fat cells of adipose tissue as triglycerides 
  • The fat cells accumulate triglycerides and expand in size. When the cells enlarge, they stimulate cell reproduction, so their numbers increase also
• Dietary risk factors: Energy intake exceed energy expenditure

  • Diets that contribute to this often consist of energy dense processed foods that are high in kilojoules and fat, increasing an individual’s energy intake and high in simple sugars, which do not provide satiety leading to overeating.
• Dietary risk factors: Portion sizes

  • Cultural expectations that people will “clean their plate” 
  • Food intake should be based on a person’s hunger and satiety levels 
  • Portion sizes have increased over time, causing Australians to overeat and consume unwanted kilojoules= weight gain 
  • Australians now consume food with a greater energy density, rather than nutrient density. 
  • Energy density= high in kJ, low in beneficial nutrients, including fibre, vitamins, minerals and proteins 
  • The average home dinner plate has increased in size from a diameter of 25cm (1970s) to up to 31cm today
• Lifestyle risk factors – Socio-economic status 

  • The highest rates of obesity are seen among groups with the lowest levels of education and income. 
  • Less access to food that are nutrient dense
  • Low food knowledge/education 
  • Low resources to engage in healthy eating and exercise 
  • Low socio-economic areas experience rates of obesity and overweight 2.3 times greater than high socioeconomic areas 
  • Males are also more likely to be overweight/ obese 
• Lifestyle risk factors - Genetics

  • Most obesity cases are not caused by genetics, but genetic influences can play a role in the development of obesity 
  • Children whose parents are both obese have a higher risk of being obese when compared to children with non-obese parents – difficult to conclude if it's from genetics or lifestyle habits 
  • An individual's genetic makeup can determine how their weight responds to certain lifestyle and diet factors
• Lifestyle risk factors – Sedentary Lifestyle

  • Individuals may be obese not because they consume too much but because they move too little 
  • The overuse of technology, including, television, video games, computers and phones are the biggest contributors to physical inactivity
  • Sedentary habits lead to weight gain, as they require little energy above an individual's basal metabolic rate
• The Role of Diet in Prevention, Control &/or Reversal

  • The aim of weight loss is to ensure that the diet provides a negative energy balance where less energy is consumed than the body needs to maintain current body weight. 
  • Energy intake < energy expenditure (negative energy balance)
  • It is essential that an individual’s energy intake provides nutritional adequacy without excess.
• The Role of Diet in Prevention, Control &/or Reversal

  • A plan that provides adequate nutrition supports healthier and more successful weight loss compared to restrictive fad diets, which are trendy weight loss plans that promise dramatic results. 
  • They can result in lowered BMR and breakdown of muscle due to very low energy supply 
  • These diets are generally kilojoule restrictive and can discourage the consumption of an entire food group – can lead to nutrient deficiencies
• Successful Diet

  A successful and well-balanced diet encourages an individual to meet the requirements of the Australian Guide to Healthy Eating (AGHE) which promotes the consumption of fruits, vegetables, wholegrains, lean meats, and low-fat milk products. And drink plenty of water.
• The Guidelines from the AGHE

  1. To achieve and maintain a healthy weight, be physically active and choose amounts of nutritious food and drinks to meet your energy needs
  2. Enjoy a wide variety of nutritious foods from these five groups every day:
  3. Limit intake of foods containing saturated fat, added salt, added sugars and alcohol
  4. Encourage, support and promote breastfeeding
  5. Care for your food; prepare and store it safely
• The Role of Lifestyle in Prevention, Control &/or Reversal

  • People who combine dietary and lifestyle management strategies are more successful in losing fat, retaining, and gaining more muscle mass, and reducing the risk of regaining the lost weight
  • Exercise expends energy, therefore increasing an individual’s energy expenditure can contribute to a negative or equal energy balance.
  • Develop more lean muscle tissue which increase BMR as lean muscle is more metabolically active than adipose tissue
• What is diabetes?

  • Diabetes mellitus describes a group of disorders, that are characterised by high blood glucose levels due to disordered insulin production.
  • This may include insufficient insulin, ineffective insulin, or a combination of the two.
  • Insulin is a hormone produced by beta (β) cells in the pancreas; it tells the body’s cells (muscle and liver) to receive glucose from the blood.
• What is diabetes?

  • After carbohydrates (except fibre) are consumed and digested, blood glucose levels rise, stimulating the pancreas to produce and release insulin into the bloodstream. 
  • Insulin then attaches to insulin receptors on the surface of body cells, triggering the cell to absorb glucose from the blood for energy production (or storage when energy needs have been met).
  • Acts as a ‘key’
• Which types of carbohydrates are metabolised and digested into glucose?

  Monosaccharides and Disaccharides and Starch
• if insulin is ineffective what would happen to blood glucose levels and predict the impact this would have on the body’s cells

  Insulin will not fit in its receptor and unlock the glucose channel, causing blood glucose levels to elevate and cause the body’s cells to be deprived of energy
• Type 1 Diabetes

  • Type 1 diabetes is an autoimmune condition in which the immune system destroys and attacks the beta cells in the pancreas 
  • Therefore, the pancreas loses its ability to produce insulin, causing blood glucose levels to continue rising
  • Inherited and commonly occurs in childhood and adolescence but can be diagnosed at any age  
  • About 10% of individuals have this type.
• Type 2 Diabetes

  • Can develop at any age – more apparent in adulthood (over 45y.o.)
  • Can be prevented or delayed with a healthy lifestyle, including a healthy weight, eating sensibly and exercising
  • Progressive condition where the pancreas is still working by producing insulin; however, the insulin does not work as effective as it should (insulin resistance)
• Type 2 Diabetes

  • To compensate the body makes more insulin but eventually cannot make enough to maintain the balance
  • This exhausts the beta cells of the pancreas leading to a reduction in insulin production 
  • Therefore, associated with a combination of insulin resistance and insufficient insulin 
• Signs and Symptoms of Type 2 Diabetes

  Hyperglycaemia

  • In type 2 diabetes, glucose slowly enters and/or fails to enter the body’s cells and consequently accumulates in the blood. This causes blood glucose levels to rise, which is known as hyperglycaemia.

  Hypoglycaemia

  • Hypoglycaemia means low blood glucose or not having enough glucose in the blood. 
• Causes of Hyperglycaemia

  • Sickness
  • Infection
  • Stress
  • Too much carbohydrate food at once
  • Not enough insulin or diabetes tablets
  • Other tablets or medicines.
• Causes of Hypoglycaemia

  • Too much insulin or other glucose lowering diabetes tablets
  • Delaying or missing a meal
  • Not eating enough carbohydrate
  • Unplanned physical activity*

  More strenuous exercise than usual*

  • Drinking alcohol – the risk of hypoglycaemia increases, the more alcohol you drink

  *Hypoglycaemia may be delayed for 12 hours or more after exercise
• Signs and Symptoms

  • Fatigue- When glucose fails to enter the body’s cells, this deprives them of energy, as glucose is a vital component in cell respiration. This leaves the body feeling fatigued, causing an increase in a diabetic’s hunger levels. This hunger can then lead to excessive eating and weight gain.
• Signs and Symptoms

  • Increased urination: a type 2 diabetic’s unusually high blood glucose levels means not all glucose can be absorbed. The excess ends up in urine. This process results in unusually large volumes of urine, which require more water. This frequent urination can lead to dehydration and excessive thirst
• Signs and Symptoms

  Blurred vision/ retinopathy/ blindness- When blood glucose levels are high over a long period of time, fluid is drawn into the eye causing it to swell. Leading to blurred vision and damage to the blood vessels behind the retina at the back of the eye.
• Signs and Symptoms

  • Gangrene- The structures of blood vessels and nerves can also become damaged due high blood glucose levels which can cause a prickling sensation followed by a loss of feeling in the hands and feet
  • This can lead to infection due to poor circulation and glucose rich blood.  Must be careful of undetected infections which can lead to gangrene 

  *gangrene is the death of a tissue due to insufficient blood supply.
• Nutrition Related Risk Factors

  Simple sugars as they enter the bloodstream rapidly causing a rapid rise in blood glucose levels and rapid energy release, stresses the beta cells of the pancreas. Also likely to have a high glycaemic index.
• Nutrition Related Risk Factors

  Dietary fat increases fat accumulation, forming an android body type, which increases adipose tissue around the pancreas, further comprising ability to produce insulin. A high fat content in the bloodstream can also build up inside cells and block the process whereby insulin signals for a cells glucose channels to open allow glucose to enter.
• The role of diet in prevention, control and/or reversal

  • Carbohydrates have the biggest impact on blood glucose levels 
  • The effect of carbohydrates depends on the amount and type of carbohydrate consumed. 
  • Individuals with diabetes should be spreading their intake of carbohydrates throughout the day to avoid causing large rises in blood glucose levels 
  • Glycaemic index (rates carbohydrates on a scale 1-100)  recommended as treatment, due to it being a measurement of how carbohydrates enter the bloodstream and affect blood glucose levels. 
  • Doesn’t consider how much carbohydrate.
• Glycaemic Index

  • The term Glycaemic index (GI) refers to how quickly glucose is absorbed after a person eats, how high the blood sugar rises, and how quickly it returns to normal.
  • It is recommended that people with diabetes have moderate amounts of carbohydrate and include high fibre foods that also have a low GI (not all high fibre foods have a low GI).
  • High GI: Fast absorption results in a surge in blood glucose and an over-reaction that drops blood glucose levels below normal
  • Low GI: Slow absorption leads to a moderate rise in blood glucose and a smooth return to normal. 
• Factors that affect the glycaemic index of food include

  • Amount and type of sugar in the food
  • The type of starch present
  • The acidity of the food
  • The fat content
  • The fibre content
• Glycaemic Load (GL)

  • More valuable in predicting a food’s effect on blood glucose levels. 
  • The GI only provides insight into how rapidly the carbohydrate can be broken down into glucose to affect blood glucose levels (its quality), but not how much of that carbohydrate is in a food serving (its quantity). 
  • Whereas the GL of a food represents the amount of carbohydrate in the food as well as its glycaemic index.
• Dietary management - CHO

  • Reduce intake of foods high in added sugars. For example sweets, lollies, soft drinks, cakes, muffins, biscuits 
  • Consume low GI/ GL food at every meal.

  For example oats, wholegrain breads, lentils, legumes, sweet potato, milk, yoghurt, pasta, fresh fruit 

  • Use sweeteners (equal, stevia, Splenda) in place of sugar
• Dietary Management - Fats

  • Fat provides the greatest amount of energy 
  • Fat intake should be limited because it can increase a person’s risk of gaining weight 
  • Individuals should choose low fat milk, cheese, yoghurt, ice cream 
  • Choose lean meat and trim excess fat 
  • Avoid using butter/ lard/ cream/ coconut milk 
  • Avoid take away/ fried food 
  • Avoid creamy dressings/ sauce 
  • Consume polyunsaturated and monounsaturated fats
• Lifestyle & Physiological Related Risk Factors and Prevention, Control &/or Reversal

  Physical Inactivity

  • A sedentary lifestyle can result in a positive energy balance, which can lead to excess kilojoules turning into weight gain.
  • Puts pressure on the already compromised pancreas
  • A lack of exercise can also cause the body’s cells to lose their sensitivity to insulin
• Lifestyle & Physiological Related Risk Factors and Prevention, Control &/or Reversal

  Alcohol 

  • Excessive alcohol consumption can cause inflammation of the pancreas leading to the destruction of the beta cells – can cause the inability to produce enough insulin.
  • Reduce the body’s sensitivity to insulin = insulin resistance
  • Alcoholic beverages are energy dense – lead to weight gain
• Lifestyle & Physiological Related Risk Factors and Prevention, Control &/or Reversal

  Genetics

  • Type 2 diabetes does not have a clear pattern of inheritance, unlike type 1 diabetes 
  • However, those that are diagnosed with type 2 diabetes will often have at least one close family member
  • The risk of developing type 2 diabetes increases with the number of close family members affected - due to shared genetic factors
  • Genetic factors are also influence by diet and lifestyle factors, which can be shared by family members