Topic 2 - Diabetes & carbohydrates Flashcards
What is Diabetes?
- Diabetes mellitus is a condition which is characterised by hyperglycaemia (high blood glucose levels)
• Blood glucose levels become too high due to the body producing little or no insulin , or not using insulin properly (insulin resistance)
• Several distinct types of diabetes exist • No cure, requires lifelong management
What is the Incidence of diabetes?
- Australia’s fastest growing chronic disease
- Approximately 1 million Australians are currently diagnosed with diabetes • Ranked in the top 10 of leading causes of death in Australia • 275 Australians develop diabetes every day
- For every person diagnosed, it is estimated that there is another who is not yet diagnosed
- By 2025 it is estimated that over 3 million Australians will have type 2 diabetes
- Diabetes costs the Australian economy $6 billion annually
- Has been identified as a national healthy priority by the federal government since 1997, yet prevalence is still on the rise
What is the prevalence of diabetes?
• More common in people 45 years+
• More males than females have diabetes
• The prevalence is greater in disadvantaged areas (almost double)
• Indigenous Australians are 3x more likely to have diabetes
• Higher among people born overseas (especially
southern and central asia)
What are the Types of Diabetes
• Pre – diabetes (2 million Australians)
– Impaired fasting glucose
– Impaired glucose tolerance
• Type 1 diabetes (10%)
• Type 2 diabetes (90%)
• Gestational diabetes (7% of all pregnancies)
• Secondary diabetes (due to pancreatic disease or steroid use)
How is Diabetes diagnosed?
- Glucose tolerance test
- Overnight fast
- 75 gram glucose load (drink)
- Venous blood glucose level taken at fasting, one hour and 2 hours post glucose load
How do we interpret results of a diabetes test
Fasting 2 Hours
Normal < 6.0 < 7.8
Diabetes >7.0 >11.1
IGT < 7.8
GDM > 5.1 > 8.5
What are the non-modifiable risk factors for Diabetes
• Family history
• Age–40years+
• Ethnicity – Aborigines or Torres Strait Islanders, Melanesian, Polynesian,
Chinese, Indian sub‐continent (AIHW 2002).
• History of Gestational Diabetes (or infant born >4.5kg)
• Polycystic Ovarian Syndrome
What are the modifiable risk factors for diabetes
Modifiable risks: • Obesity/ Overweight • Sedentary lifestyle • Heart Disease / High Blood Pressure / High cholesterol • High fat diet • Smoking
Discuss modifiable risk factors
• Overweight adults risk x3
• Obese adults possibly x10 (AIHW 2002)
• Physical activity and diet modification can delay or prevent progression to Type 2 diabetes
• People with diabetes are – more likely to do no, or have a low level of exercise, and
–be known to be obese or overweight (54.9% compared with 33.6%).
How does our shape influence diabetes
Apple shape a more powerful determinant of risk for type 2 diabetes than BMI and pear shape
Discuss type 2 diabetes
- 90% of all people with diabetes have Type2
- Common for people to have no symptoms
- Usually discovered by routine screening or with other co‐morbidities
- Strongly associated with high blood pressure, high cholesterol, overweight esp. abdominal fat
- Insulin resistant–pancreas is producing insulin but it is not able to do it’s job. Fat forms a physical barrier &/or tissues are less responsive to insulin.
Discuss diabetes and insulin connections
In Diabetes… Insulin cannot effectively transport Glucose into the cells.
Describe type 1 diabetes
• Only 10 of all people with diabetes have Type 1 diabetes
• Over 5700 children aged 0‐14 have Type 1 diabetes (2008)
• Usually affects children and young adults (<18years)
• Sudden onset and symptomatic – thirst, weight loss,
urinating frequently, blurred vision
• The pancreas cannot produce insulin ‐ beta cells have been destroyed
• Insulin injections absolutely necessary
Describe gestational diabetes
• Approximately 7% of pregnant women develop gestational diabetes around 24 _28 weeks of pregnancy
– >30years – Family history of diabetes – Overweight pre‐pregnancy
• 30‐50% increased risk of type 2 later in life
• Pregnancy = insulin resistant. This allows the baby to grow
and develop.
• If undiagnosed the baby grows bigger much faster
(macrosomia). Increased risk of baby developing type 2 diabetes later in their life.
Discuss Impaired Glucose Tolerance
Important pre‐diagnostic state
• If left, may develop Type 2 diabetes within 5‐10 years
• Weight loss critical for prevention –↓10%
• Physical activity key to encouraging more efficient glucose uptake
• Early referral to a Dietitian
What are the management of diabetes
• Diet
• Exercise
• Blood Glucose Monitoring
• Insulin injections
• Oral medications for Type 2 – Sulfonylureas increase insulin secretion and prepares
peripheral tissues. – Metformin decreases hepatic glucose production, increases
glucose uptake and possibly decreases appetite.
– Others slow the absorption of carbohydrates or decreases insulin resistance.
What are diabetes complications
- Lower limb nerve damage affects 13% of people with diabetes
- Diabetes retinopathy affects 15%
- Leading cause of end stage kidney disease
- Cardiovascular disease is leading cause of death in people with diabetes (65% of all CVD deaths)
- Poor psychological well being in 41% of people with diabetes
Goals of Diabetes Management – how to prevent complications?
- Achieve and maintain optimal blood glucose control (HbA1C 7% or less)
- Obtain optimum blood lipid levels
- Obtain and maintain an appropriate weight and a healthy blood pressure
- Prevent and treat the acute short term complications of diabetes eg hypoglycaemia
- Prevent and treat long term complications of diabetes such as renal disease, hypertension and cardiovascular disease
- Improve overall health through optimal nutrition
Diabetes Control and Complications
- Diabetes Control and Complications Trial (DCCT) and UK prospective Diabeets Study ( UKPDS) with people who have Type 1 and Type 2 diabetes
- Large, long term, multi centre trials over 18 (DCCT) and 30 (UKPDS) years respectively
- Patients who maintained HbA1c levels around 7% had much better health than those whose HbA1C was around 9%.
- Lower complications of retinopathy, nephropathy, neuropathy.
List carbohydrate food sources
Bread
Cereal - special K, All Bran, Weetbix, Uncle toby’s
Rice, Pasta, Noodles
Corn
Potato, Sweet potato
Legumes, Baked beans, Lentils
Apples, Banana, Cherries, Pear, Pineapple, Grapes, Kiwi Fruit, Mandarin, Orange, Watermelon
Dried Apples, apricots, sultanas
Tinned Fruit
Fruit Juice
Milk, Yoghurt, Sorbet, Low fat Custard/ice-cream
Biscuits, Vita-Weat crackers, Pancakes, Rice Cakes
List some free foods that don’t raise BGLs
Vegetables; celery, carrot, capsicum, pumpkin
Proteins - fish, meat, tinned seafood
Fats; margarine, avocado, peanut butter, oils
Strawberries
Discuss classes of carbohydrates
Sugars (1-2 sugars); Monosaccharides: Glucose, fructose Disaccharides: Sucrose, lactose Oligo-saccharides (3-9 sugars); Malto-oligosaccharides: Maltodextrin Other: Inulin, stacchyose Starch: Amylose Polysaccharides (>9 sugars) Non-starch polysaccarides: Cellulose, pectin
Describe carbohydrate digestion
- Some starch broken down by salivary amylase to maltose
- Salivary amylase inactivated by strong acid
- Absorption of glucose, fructose, and galactose into blood to be taken to the liver
- Enzymes (amylase) from pancreas break down starch into maltose
- Enzymes in wall of intestine break down disaccharides, sucrose, lactose and maltose into monosaccharides, glucose, fructose and galactose
- Some fibre digested into various acids and gases by bacteria in the intestine
- Some fibre excreted in faeces but little other dietary carbohydrate is present
What are the 3 main management points for carbohydrates and Diabetes
- Variety
- Amount
- Type – Glycaemic Index
Discuss Carbohydrates and Diabetes Management ‐ Variety
• Important to eat a variety of carbohydrate foods to meet requirements for energy, vitamins, minerals, fibre. • Australian Guide to Healthy Eating – Breads and cereals – Fruit – Dairy
Discuss Carbohydrates and Diabetes Management ‐ Amount
• Avoid large carbohydrate loads at meals by spreading these foods over the day.
• Large CHO load meal = higher after meal BGL
• Most people will consume 3 carbohydrate
containing meals and 2‐3 snacks per day
• Carbohydrate exchanges are a tool used to assist people with diabetes to spread carbohydrates over the day
Carbohydrate: What is an exchange?
A “serve” or “exchange” is the quantity of a food which contains 15 grams of carbohydrate.
E.g.
1. 1 piece of fruit or 1/2 glass fruit juice
2. 1 slice of bread
3. 1 glass of milk
4. 2 plain biscuits
5. 1/2 cup cereal
6. 1/3 cup cooked rice/pasta
7. 1 medium potato
8. 1/2 cup legumes & corn
9. 200g plain yoghurt or 100g flavoured yoghurt
How many carbohydrate exchanges should people with diabetes consume?
• Individual and based on individual energy requirements
• 45‐65% of energy from carbohydrate
• As a guideline for type 2 diabetes
– 2‐3 carbohydrate exchanges at main meals
– 0‐2 carbohydrate exchanges at snacks
Carbohydrates and Diabetes Management ‐ Type
Not all Carbohydrates are the Same
The Glycaemic Index developed in 1981 by Dr David Jenkins
GI classifies Carbohydrates based on their affect on Blood Glucose levels
GI is a measure of carbohydrate
Discuss GI
GI is a way of ranking foods that contain carbohydrate according to the effect they have on blood sugar levels
High GI:
Quick break down and absorption –> Rapid rise & fall in blood glucose
Low GI:
Slower break down and absorption –> Gradual rise in blood glucose
Discuss low GI tips
Tips to lower the overall GI of meals:
Include at least one low GI food with each meal
and snack
Include protein in meals and snacks Use vinegar and lemon/lime juice
dressings/sauces. The acidity lowers the G.I
Fats, and physical state of the starch also affect G.I
‐ Starch gelatinisation
‐ Particle Size
‐ Physical entrapment
‐ High amylose to amylopectin ratio
‐ Viscosity (thickness) of Fibre
What are the Benefits of A Low GI Diet
Weight Control Decrease feelings of hunger
Longer lasting energy
Improve Blood Fats Decrease LDL and Trigs
Increase HDL
Improve Blood Glucose Levels
Improves Insulin Sensitivity
Basic Meal Planning for Diabetes
- Choose 2‐3 low G.I carb exchanges
- Add in protein
- Add in free foods
Advice to People with Diabetes about Carbohydrates
- Eat a variety of foods
- Avoid large loads of carbohydrates at meals by spreading these over the day eg 2‐3 exchanges per meal and 0‐2 per snack
- Include as many low G.I choices as possible but aim for at least one low G. food per meal
