The Glycaemic Index — Why It Matters
Foods that break down quickly into glucose spike blood sugar (high GI). Foods that break down slowly cause a gentle rise (low GI). For diabetes management, choosing low-GI foods reduces post-meal glucose spikes.
| GI Category | Examples | Effect on Blood Sugar |
|---|---|---|
| Low GI (<55) | Oats, lentils, chickpeas, most fruit, sweet potato | Gentle, sustained rise — ideal |
| Medium GI (55–70) | Brown rice, wholegrain bread, quinoa | Moderate rise |
| High GI (>70) | White bread, white rice, sugary cereal, sports drinks | Rapid spike — limit these |
Best Dietary Patterns for Diabetes
| Diet Pattern | HbA1c Effect | Evidence Level |
|---|---|---|
| Low-carbohydrate (<130g/day) | Strongest HbA1c reduction (up to 1.5%) | Strong |
| Mediterranean diet | Reduces HbA1c by ~0.5–1.0% | Strong |
| Plant-based / vegan | Moderate benefit for T2DM | Moderate |
| DASH diet | Particularly good for BP + diabetes | Strong |
| Very low calorie (<800 kcal) | Can induce T2DM remission | Strong (supervised only) |
Remission Is PossibleFor type 2 diabetes, losing 10–15% of body weight through a structured low-calorie diet (800–1000 kcal/day for 8–12 weeks) can put diabetes into full remission in up to 50% of people within the first year. Ask your GP about the NHS Low Calorie Diet programme.
Foods to Eat More Of
- Non-starchy vegetables (broccoli, spinach, cauliflower, peppers) — unlimited
- Legumes (lentils, beans, chickpeas) — low GI + high fibre + protein
- Oily fish (salmon, mackerel, sardines) — 2× per week for heart health
- Nuts and seeds — healthy fats, protein, low carb
- Whole grains (oats, barley, quinoa) in moderation
- Berries — lower sugar than other fruit, rich in antioxidants
Foods to Limit or Avoid
- Sugary drinks (fruit juice, fizzy drinks, energy drinks) — the worst
- Refined carbohydrates (white bread, white rice, pastries)
- Ultra-processed foods (crisps, biscuits, ready meals)
- Full-fat dairy and red meat in excess
- Alcohol — raises blood sugar acutely, then causes hypoglycaemia
Can I eat fruit with diabetes?
Yes — but choose lower-sugar fruits (berries, apples, pears) and limit high-sugar fruits (mango, banana, grapes). Whole fruit is much better than juice, which removes the fibre.
Does eating fat raise blood sugar?
Fat itself does not raise blood sugar directly, but fatty meals slow glucose absorption and can cause a delayed rise 3–5 hours after eating (especially important for insulin users).
Should I count carbohydrates?
Carbohydrate counting is particularly important for type 1 diabetes (to match insulin doses). For type 2, focusing on overall carbohydrate quality and portion control is usually more practical.
Is artificial sweetener safe in diabetes?
Most artificial sweeteners (stevia, erythritol, sucralose) don't raise blood sugar and are generally considered safe in moderate amounts. Some evidence suggests they may affect gut bacteria with long-term use.
Medical Disclaimer: This page is for general education only and does not replace professional medical advice. Always consult a qualified healthcare provider.