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What is Carbohydrate Awareness?
Carbohydrate awareness means learning how the carbohydrates you eat affect your blood sugar levels when you have diabetes. By understanding carbs better, you can make choices that help keep your blood sugar steady.
What is a Carbohydrate?
Carbohydrate (often called carbs is one of the three main nutrients in food.
The other two are fat and protein.
There are three types of carbohydrate:
- Sugar
- Starch
- Fibre
When you eat carbohydrate, your body breaks it down into glucose (sugar), which goes into your bloodstream. Your body then needs insulin to help move the glucose from your blood into your cells, where it is used for energy.
Your pancreas makes insulin. If your pancreas doesn’t make enough, you may need to take insulin as an injection.
How Do Carbohydrates Affect Blood Sugar?
Carbohydrates have the biggest effect on your blood sugar levels. Fat and protein have very little effect.
The amount of carbohydrate you eat is the main thing that changes your blood sugar, but the type of carb matters too.
Some carbs raise blood sugar slowly, and some raise it quickly.
You might hear this called the Glycaemic Index (GI):
- Low-GI foods (slow release) → cause a gentle, slow rise in blood sugar
- High-GI foods (fast release) → cause your blood sugar to rise more quickly
There will be more information about GI later in the booklet.
Sources of Carbohydrate
-
Bread: all types
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Breakfast cereals: e.g. porridge, shreddies, rice krispies, weetabix etc
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Starchy vegetables: potato, corn, sweet potatoes
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Grains: rice, pasta, couscous, barley, bulgar wheat, noodles
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Fruit: fresh, dried, tinned, fruit juice
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Dairy foods: milk, yoghurt, ice cream, custard
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Legumes: pulse, vegetables e.g. peas, baked beans, red kidney beans, lentils, chickpeas
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Baked foods: cakes, biscuits, crackers, pizza, pastries
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Confectionary: chocolate, sweets
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Snack foods: potato crisps, popcorn
Starchy Carbohydrate
Starchy carbohydrate is found in potatoes, rice, pasta, noodles, bread, breakfast cereal, oats, couscous, corn and pulse vegetables, such as lentils, chickpeas and red kidney beans.
These foods are the main source of carbohydrates and provide other important nutrients like vitamins and fibre. It is important to include some of these foods in your diet.
Sugars
There are different kinds of sugars. Here are the main ones you’ll hear about:
Sucrose
This is the sugar you find in things like sweets, cakes, biscuits, and in sugary drinks.
It’s the type of sugar people add to food to make it taste sweet.
- Try to keep foods with added sugar to a minimum
- Sugary foods are often also high in fat, which can make you gain weight
- Choose diet or no added sugar drinks instead of sugary ones
Fructose (fruit sugar)
This is the natural sugar in fruit, including:
- Fresh fruit
- Dried fruit
- Canned fruit
- Fruit juice
Fruit does raise your blood sugar, but it’s still important because fruit gives you vitamins, minerals and fibre. Problems usually happen when someone eats too much fruit at once or drinks large amounts of fruit juice.
Lactose
This is natural milk sugar and is found in milk, yoghurt and fromage frais.
Which Foods do not Contain Carbohydrate?
Protein foods e.g. meat, poultry, fish, eggs and most cheeses are unlikely to contain carbohydrate unless coated in flour or breadcrumbs.
Sources of fat, such as oils, butter and spreads do not contain carbohydrate.
Amount of Carbohydrate
The more carbohydrate you have in your diet the higher your blood glucose level will rise. To get an idea of how much carbohydrate you are eating each day, add up the total amount of carbohydrate from all the food you eat. Do this for a few days to get an idea of your average daily intake. Your Dietitian will be able to help you with this.
If the quantity of carbohydrate (total of starchy and sugary carbohydrate) in the diet fluctuates too much, it can lead to variable blood glucose levels. Try to avoid this by aiming for consistent amounts of carbohydrate eaten at each mealtime on a day-to-day basis.
How Much Carbohydrate Should You Have?
Carbohydrate (carb) is the main thing that makes your blood sugar go up. So, the more carbs you eat, the higher your blood sugar will rise. To understand how much carb you normally eat, you can:
- Add up the total carbs in everything you eat and drink each day
- Do this for a few days
- Then you can see what your average daily carb intake looks like
Your dietitian can help you with this and check if you’re eating the right amount for you.
Why Does Consistency Matter?
If the amount of carbohydrate you eat changes a lot from day to day, your blood sugar levels can go up and down more than you want.
To help keep your blood sugar steady, try to:
- Eat similar amounts of carbohydrate at each meal
- Keep your meals fairly consistent from one day to the next
This doesn’t mean your meals have to be the same — just try not to have a huge amount one day and very little the next.
Calculating the Carbohydrate Content of Your Food
You can use the following resources to help to estimate the amount of carbohydrate in your portion.
You will find the following resources useful:
- Food labels (from the foods you are eating)
- Carbohydrate reference tables (provided by your dietitian)
- Carbs and Cals book, or app available from the App store or Google play (http://
www. )carbsandcals.com - My Fitness Pal app
Using Food Labels
Food labels can help you find out how much carbohydrate is in your food. This is important when you’re counting carbs for diabetes. When you look at a food label, check:
- Carbohydrate per serving
Some labels tell you how many carbs are in one serving (like 1 biscuit or 1
slice of bread). But make sure the serving size on the packet is the same amount you’re
actually eating. If you eat more or less, the carbs will be different.
- Carbohydrate per 100g
If your serving is a different size from the one on the packet, look at the carbs per 100g. You can use this number to work out the carbs in your own portion. Your dietitian can show you how to do this and help you practise.
When reading food labels, always check the TOTAL carbohydrate. This number includes both starch and sugars, so it gives you the full amount you need for carb counting.
If you have weighed your food and looked up the carbohydrate content of it per 100g, use the following formula to work out the carbohydrate content of your portion.
Carbohydrate content = weight of your food x carb content of food per 100g
Example
- Weight of new boiled potato = 120g
- Carbohydrate content of boiled, peeled potatoes = 17.8g/100g
- Carbohydrate content of portion = 120 x 17.8 = 21.36g carbohydrate
100
How Much Carbohydrate Should I Eat?
The amount of carbohydrate each person needs is different. It depends on things like:
- Your age
- Your gender
- How active you are
- Your body size and weight
Your dietitian will help you understand how much energy and carbohydrate you need each day, and how to spread this out across your meals and snacks. If you need to, you can write this information on the chart on page 6.
Ranges of carbohydrate intake:
- High carbohydrate intake: >225g
- Medium carbohydrate intake: 130g-225g
- Low carbohydrate intake: <130g
Publications Which Can Help with Assessing Carbohydrate Content of Foods
Carbs and Cals’ by Chris Cheyette and Yello Balolia
Published by Chello Publishing 2010
This publication gives the carbohydrate content of different serving sizes of various foods in pictorial form. You may find it useful to refer to this to help with assessing the carbohydrate content of your meals or snacks, particularly when outside the home.
There is also an IOS and Android app version available to download.
More information is available from the website:
Ideas to Help You Have Consistent Amounts of Carbohydrate
It’s important to try to eat similar amounts of carbohydrate at each meal every day. This helps keep your blood sugar levels steady.
Start With Breakfast and Lunch
Most people eat similar foods for breakfast and lunch every day. Because these meals don't change much, they are the easiest meals to keep your carb amounts the same.
What About Weekends or Special Occasions?
On weekends, birthdays, or meals out, you might eat different foods. You can still keep your carbohydrate amount similar by swapping foods.
Example: If you’re having a restaurant meal and want a dessert, you could:
- Skip the potatoes with your main meal
- Then enjoy your dessert instead
This helps you keep your total carbs similar to your usual meal. But remember: Desserts often have more sugar and fat, so it’s best not to do this too often.
Common Foods That Can Result in a Larger Carbohydrate Intake Than You Realise
Fruit
Fruit is healthy, but fruit sizes have got bigger over the years. That means some fruit now contains more carbohydrate than people realise.
- • A large banana can have almost the same amount of carbohydrate
- as 2 slices of bread!
- • Try a fun-size banana, or eat half now and half later.
Pasta/Rice Meals
Pasta and rice can be very high in carbohydrate, especially when served with
sauces.
- Try swapping some of the pasta or rice for vegetables or salad.
- Add protein (like chicken, fish, Quorn, or beans) to make the meal more filling without adding lots of extra carbs.
Bread as a Side Order
If you enjoy having bread, chapatti, or naan with your meal, remember these
all add extra carbohydrate.
- If you’re having bread on the side, try reducing the amount of potato, pasta, or rice on your plate.
Restaurant/Takeaway Portion Size
Portions in restaurants or takeaways are often much bigger than at home.
- If you eat out a lot, try to eat a similar amount to what you would at home.
- You could ask for a smaller portion or share a meal.
Sauces
Some ready-made sauces contain a lot more carbohydrate than you might
expect.
Examples include:
- Sweet and sour sauce
- Some pasta sauces (especially those with added sugar or flour)
Tip: Try making your own versions at home — they’re often healthier and lower in carbs.
Jacket Potatoes
Jacket potatoes shrink when cooked, but the carbohydrate stays the same. This means they can contain more carbs than they look like.
- Potatoes in restaurants are often huge, so consider eating half.
- New potatoes are a good option because their carbs are slow release (but still stick to a portion of about 4 egg-sized potatoes).
Coffee and Cake
Stopping for a snack can add a lot of carbohydrate without you realising.
- Large coffees often contain lots of milk, which has natural sugar.
- A big muffin, like a blueberry muffin, can have a very high carb content. Try a mini muffin and a cup of tea instead!
What About the Glycaemic Index of Foods?
The Glycaemic Index (GI) tells us how quickly a carbohydrate food makes your blood sugar rise.
- Low-GI foods (slow release) → make your blood sugar rise slowly and steadily
- High-GI foods (fast release) → make your blood sugar rise more quickly
Eating more slow-release (low-GI) foods can help stop your blood sugar from jumping up too much after meals.
But GI Isn’t Everything! GI can be helpful, but it’s not the only thing that makes a food healthy. Here are some important things to remember:
High-GI foods can still be healthy
Some foods like:
- Wholemeal bread
- Jacket potatoes have a high GI, but they are good for you because they give you fibre and important nutrients.
Some low-GI foods aren’t always healthy
Foods high in fat (like chocolate or chips) may have a low GI because fat slows down digestion, but that doesn’t mean they’re healthy or good to eat often. So, don’t choose foods just because they have a low GI.
The amount of carbohydrate still matters most. Even though GI tells you how fast carbs work, the total amount of carbohydrate you eat has the biggest effect on your blood sugar.
To lower the GI of your diet, try and choose foods from the slow-release section in the following tables.
| Slow release or Low GI foods | Medium release or Medium GI foods | Fast release or High GI foods |
| Apples, oranges, pears, peaches, plums, grapefruit, grapes, apricots (fresh or dried), banana (yellow with green sections), mango, strawberries, cherries, blueberries |
Banana (yellow with black spots), melon, dried fruit, pineapple, dates, kiwi, raisins |
Watermelon |
| All beans, lentils, chickpeas, split peas | ||
| Nuts and seeds | ||
| White or wholemeal pasta, egg pasta | Gnocchi, udon noodles, rice vermicelli noodles | Gluten free pasta, corn pasta, rice pasta, canned spaghetti |
| Brown rice, bulgar wheat, buckwheat, quinoa, pearl barley, microwave rice | Basmati rice, wild rice, couscous, arborio rice, polenta, long grain rice | Short grain rice, fast cook long grain rice, sushi rice, jasmine rice, instant rice, tapioca |
| Rolled oats, no added sugar, museli, all bran, porridge | Mini wheats, shredded wheat, weetabix, oatibix, instant porridge, special K, fruit and fibre, sultana bran | Cornflakes, crunchy nut cornflakes, rice krispies, puffed wheat, coco pops, cheerios |
| Multi-grain or mixedgrain bread, soya and linseed bread, granary bread, oatbran bread, chapattis, rye bread, tortilla wraps, fruit loaf, sourdough, seeded bread, pumpernickel bread |
Crumpets, rye crisp bread, pitta bread, croissant, taco shells, malt bread |
White, wholemeal and brown bread, baguettes, bagels, melba toast, Naan bread, English muffins |
| Oat cakes, Rich Tea biscuits, fruit loaf, tea cakes, Ryvita with seeds |
Ryvita, plain digestive biscuits, shortbread, muesli bars, popcorn (plain/salted), flapjack, crisps |
Waffles, water biscuits, rice cakes, cream crackers, corn thins, pretzels |
| Milk (all dairy), low fat yoghurt, ice cream, custard, soya products |
Sorbet, oat milk | Rice milk |
| Sweet potato | New or boiled potatoes, chips/fries | Jacket/mashed potato, instant potato |
Contact us
If you have any queries relating to this information, please contact the Dietetics service.
About this information
Service:
Dietetics
Reference:
DT/026
Approval date:
1 March 2026
Review date:
1 March 2029
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Important note
This page provides general information only. It is developed by clinical staff and is reviewed regularly every 3 years for accuracy. For personal advice about your health, or if you have any concerns, please speak to your doctor.