Low GI Foods List UK: What to Eat for Steadier Blood Sugar

Low GI foods are carbohydrate foods with a glycaemic index of 55 or below, so they raise blood sugar slowly. A UK low GI foods list includes most fruit and veg, beans, lentils, steel-cut oats, rye bread, yam, plantain and unsweetened milk and yoghurt. GI is a useful tool, but the amount of carbohydrate you eat matters even more.

What is the glycaemic index?

The glycaemic index (GI) ranks carbohydrate foods and drinks on a scale of 0 to 100 by how quickly they raise blood sugar. Diabetes UK uses three bands:

• Low GI: 55 or below, raises blood sugar slowly
• Medium GI: 56 to 69, raises blood sugar at a moderate rate
• High GI: 70 or more, raises blood sugar quickly

Only foods that contain carbohydrate have a GI. The British Dietetic Association (BDA) notes that carbs from starchy foods and from added and natural sugars all raise blood glucose.

Which foods are low, medium and high GI?

Here are examples from Diabetes UK’s lists. Values can vary between brands and with how food is cooked, so treat this as a rough guide.

Diabetes UK points out that most fruit and vegetables are low or medium GI. They also bring fibre and vitamins such as vitamin C, so there’s no need to avoid them.

The BDA’s own list adds more low GI options, including jumbo oats, unsweetened muesli, barley, bulgur wheat, quinoa and pasta cooked until al dente (still firm). Sources don’t always agree on every food: the BDA counts basmati rice as low GI, while Diabetes UK puts it in the medium band.

Is low GI always healthier?

No. Diabetes UK is clear that GI on its own doesn’t tell you whether a food is healthy.

• Chocolate is low GI mainly because of its fat content.
• Crisps have a lower GI than potatoes cooked without fat.
• A baked potato is high GI but still gives you useful nutrients, especially in the skin.

A diet chosen only by GI could still be high in fat and calories. Diabetes UK says that can lead to weight gain and raise your risk of heart disease. Use GI to choose between similar foods, such as one type of bread over another, rather than as the only rule.

Why portion size matters more than GI

GI tells you how fast a food raises blood sugar, not how much carbohydrate is in your portion. The BDA says portion size often has the biggest effect on blood glucose.

That’s where glycaemic load comes in. It takes into account both the GI and the amount of carbohydrate. Diabetes UK gives a good example: pasta has a lower GI than watermelon but contains more carbohydrate, so a similar amount of pasta can raise blood sugar more.

As a rough guide, the BDA suggests a fist-sized portion of starchy food for most adults, or a quarter to a third of your plate depending on how active you are. Our guide is rice bad for diabetes shows how this works with one everyday food.

What changes the GI of a food?

The same food can have a different GI depending on how you prepare it. According to Diabetes UK and the BDA:

1. Cooking: frying, boiling and baking all change GI. Pasta cooked al dente has a lower GI than soft, overcooked pasta.
2. Cooling and freezing: the BDA says cooling starchy foods after cooking, and freezing or toasting bread, lowers their GI.
3. Processing: milling and puréeing can change a food’s GI. Less processed, higher-fibre foods generally have a lower GI.
4. Ripeness: riper fruit raises blood sugar faster. The BDA mentions yellow or brown bananas, mango and pineapple.
5. Fibre, fat and protein: these slow digestion. Eating carbs with protein, healthy fats and vegetables lowers the overall effect of a meal.

Diabetes UK also notes that wholegrain isn’t the same as wholemeal. Wholemeal just means the grain has been ground, which is why some wholemeal breads are still high GI.

How does GI help with diabetes?

Diabetes UK says choosing low GI foods can help people with type 2 diabetes manage their long-term blood sugar (HbA1c). Swapping high GI foods for lower GI ones can also help manage blood sugar in gestational diabetes.

For type 1 diabetes, the evidence is weaker. Diabetes UK says low GI foods can still help keep blood sugar levels steady after eating.

If you take medication for diabetes, the BDA advises speaking to your healthcare professional before changing your diet. Talk to your GP, diabetes nurse or dietitian, and ask your GP about a referral to a dietitian for advice that fits you.

Easy low GI swaps to try

The BDA’s tips make GI easy to use day to day:

• swap white bread for wholegrain, seeded, rye or oat bread
• choose jumbo or steel-cut oats instead of instant oats
• add beans, lentils or chickpeas to stews, soups and salads
• keep the skins on potatoes, fruit and vegetables
• pick less ripe fruit, and keep fruit juice to no more than 150ml a day
• swap sugary drinks for water or herbal tea
• have fruit and nuts, or veg sticks with hummus, instead of biscuits and crisps

For more ideas between meals, see our best snacks for type 2 diabetes.

Checking meals without a label

GI is harder to judge when you’re eating out or someone else has cooked. The Dietary Insight app can estimate the sugar, salt and fat in a meal from a photo and suggest a swap, which can help you spot the carb-heavy parts of the plate.