Nutrition and Energy (Blood Glucose Maintenance and Diabetes)

Question 1

What is a healthy blood glucose concentration?

Answer 1

4-6 mmol/L

Question 2

What two hormones does a healthy pancreas secrete to regulate blood glucose levels?

Answer 2

Insulin and Glucagon

Question 3

Beta cells in the pancreas secrete which hormone? What triggers this secretion?

Answer 3

Beta cells secrete insulin in response to high blood glucose

Question 4

Alpha cells in the pancreas secrete which hormone? What triggers this secretion?

Answer 4

Alpha cells secrete glucagon in response to low blood glucose

Question 5

Does insulin act to raise or lower blood glucose level? How?

Answer 5

Insulin acts to lower blood glucose by binding to insulin receptors on cells, opening glucose channels and triggering the uptake of blood glucose (and fatty acids) into cells for storage and usage

Question 6

Does glucagon act to raise or lower blood glucose level? How?

Answer 6

Glucagon acts to raise blood glucose by triggering the breakdown of liver glycogen into glucose and stimulating the release of glucose and fatty acids from stores into the blood

Question 7

What feedback relationship do insulin and glucagon have with each other?

Answer 7

A negative feedback loop

Question 8

As blood glucose levels rise, what happens to glucagon secretion?

Answer 8

It slows

Question 9

As blood glucose levels fall, what happens to insulin secretion?

Answer 9

It slows

Question 10

What is low blood sugar known as? What symptoms can this cause?

Answer 10

Hypoglycaemia

Symptoms include:
Irregular heart rate
Fatigue
Pale skin
Shakiness
Anxiety
Sweating
Hunger
Irritability
Tingling/numbness in lips/tongue/cheeks

Question 11

What is high blood sugar known as? What symptoms can this cause?

Answer 11

Hyperglycaemia

Symptoms include:
Increased urination
Increased thirst
Blurred vision
Fatigue
Headache

Question 12

Which type of diabetes is an auto-immune condition? What is the immune system attacking and what does this result in?

Answer 12

Type 1 diabetes

The immune system attacks beta cells in the pancreas, leading to little to no production of insulin (insulin deficiency)

Question 13

How is Type 1 diabetes typically diagnosed?

Answer 13

Through blood tests

Question 14

How is Type 1 diabetes typically managed and treated?

Answer 14

Insulin injections (often synthetic insulin),
Monitoring blood glucose (finger prick or pump),
Carb counting (working with a dietician),
Physical activity (increases insulin sensitivity).
Eating good quality food

Question 15

Which type of diabetes isn’t the result of an auto-immune condition? What is the source of the problem in this type?

Answer 15

Type 2 diabetes

The body fails to produce insulin correctly or the pancreas fails to make enough insulin due to insulin insensitivity

Question 16

How is Type 2 diabetes typically managed and treated?

Answer 16

Setting dietary patterns,
Weight loss,
Monitoring blood glucose,
Medications (Metformin increases insulin sensitivity),
Insulin injections (if diabetes progresses)

Question 17

Which type of diabetes is more prevalent?

Answer 17

Type 2 diabetes (90-95% of diabetes cases)

Type 1 diabetes (5-10% of diabetes cases)

Question 18

What are some symptoms of diabetes?

Answer 18

Excessive hunger: Tissues/cells not getting any energy, drives hunger response and excessive eating (polyphagia)
Extreme thirst: Dehydration from polyuria leads to extreme thirst and water consumption (polydipsia)
Weight loss
Frequent urination: may also be sugary (glucosaria), leading to osmotic stress increasing urine output (polyuria)
Slow healing cuts
Blurred vision
Lethargy
Numbness in hands or feet

Question 19

Why does diabetic ketoacidosis occur in untreated diabetic individuals?

Answer 19

Even if blood glucose levels are high, if the cells cannot use it, the body will think it’s in a period of fasting, resulting in the breakdown of triglyceride stores (lipolysis), releasing glycerol and free fatty acids for conversion into glucose.

Fatty acids undergo beta-oxidation in the liver and produce ketones, which raises ketone blood concentration and leads to ketoacidosis.