Types of Diabetes and Their Treatment Revision Notes | GCSE Edexcel Higher Biology

1. When Blood Sugar Goes Wrong

Your body runs on glucose like a car runs on petrol. But what happens when the fuel delivery system breaks down? Diabetes affects millions of people worldwide, turning the simple act of eating into a complex medical challenge.

There are two main types of diabetes, and they're as different as a broken fuel pump versus a blocked fuel line. Understanding these differences isn't just academic - it determines how each condition is treated and managed.

2. The Two Faces of Diabetes

Think of Type 1 diabetes as a factory shutdown. The insulin-producing cells in the pancreas have been destroyed, usually by the body's own immune system. No insulin means glucose can't enter cells, so it builds up in the blood to dangerous levels.

Type 2 diabetes is like having a key that no longer fits the lock. The pancreas produces insulin (the key), but the cells have changed and won't respond to it properly. The glucose stays locked out of the cells.

Here's where students often get confused about the key differences. Let's test your understanding:

3. Treatment Strategies - Matching the Solution to the Problem

Since the causes are different, the treatments must be different too. You can't fix a broken factory the same way you'd fix a jammed lock.

Type 1 Treatment: Insulin Injections

If your pancreas can't make insulin, you need to inject it. Type 1 diabetics inject insulin multiple times daily, usually before meals. The insulin allows glucose to enter cells, preventing dangerous blood sugar spikes.

Type 2 Treatment: Lifestyle First

Since cells are resistant to insulin, we need to make them more sensitive again. A carbohydrate-controlled diet reduces the glucose load, while exercise makes cells more responsive to insulin. Weight loss is crucial because obesity worsens insulin resistance.

**Trap**: Many students think Type 2 diabetics always need insulin injections. Actually, lifestyle changes are the first-line treatment, and many people can manage Type 2 without injections.

4. Reading the Graphs - Blood Glucose Patterns

Exam questions love to show you graphs of blood glucose levels over time. Here's how to read them like a detective:

Worked example: Interpreting Blood Glucose Graphs

A graph shows blood glucose levels after eating. Person A's glucose rises to 8 mmol/L then returns to 5 mmol/L within 2 hours. Person B's glucose rises to 15 mmol/L and stays high. Identify who has diabetes and what type.

1. Person A: Peak 8 mmol/L, returns to baseline quickly — Normal blood glucose control - insulin working properly
2. Person B: Peak 15 mmol/L, stays elevated — This shows poor glucose control - diabetes present
3. High peak + no recovery = insufficient insulin response — Could be Type 1 (no insulin) or severe Type 2 (major resistance)
4. Need age, weight, family history for definitive diagnosis — Young, thin = likely Type 1; Older, overweight = likely Type 2

Answer: Person B has diabetes. Type depends on additional clinical factors, but the graph shows clear insulin insufficiency.

The key pattern to spot: normal individuals show a glucose spike after eating, then a rapid return to baseline. Diabetics show higher spikes and slower (or no) return to normal.

5. Risk Factors and Prevention

**Obesity and Type 2 Diabetes: The Dangerous Connection**

Obesity is a major risk factor for Type 2 diabetes. Excess fat tissue, especially around the abdomen, releases chemicals that make cells less responsive to insulin. This creates a vicious cycle: insulin resistance leads to weight gain, which worsens insulin resistance.

Type 1 diabetes, however, cannot be prevented - it's an autoimmune condition that destroys insulin-producing cells regardless of lifestyle factors.

6. Exam Success - Getting Full Marks on Diabetes Questions

Diabetes questions appear frequently in GCSE exams, often worth 4-6 marks. Here's how to maximise your score:

Exam depth extension: In types of diabetes and their treatment, connect when blood sugar goes wrong to the two faces of diabetes using clear cause-and-effect statements. When you explain biological processes, include what changes, why it changes, and the consequence for cells, organisms, or populations. If calculations appear, show each step, include units, and end with a sentence that interprets the result in biological context.

**Common Exam Mistakes to Avoid:**

- Saying Type 2 diabetics 'don't produce insulin' (they do, but cells don't respond)

- Forgetting to mention that obesity is a risk factor for Type 2 specifically

- Not explaining WHY each treatment works for each type