Why does my body need carbohydrates?

What are carbohydrates?

Carbohydrates are your body’s main source of energy. While fats and protein also provide energy, carbohydrates are the preferred type of energy source. This is because they’re quickly turned into sugar (glucose). This glucose is essential for your brain and nervous system. Your body also uses glucose for exercise and other functions.

Wholegrain, starchy carbohydrates are also an important source of essential nutrients and fibre.

What types of carbohydrates are there?

There are two main types of carbohydrates: complex carbohydrates and refined carbohydrates.

Complex carbohydrates include:

• wholegrain bread
• brown rice
• jumbo oats
• wholewheat cereals
• potatoes with the skin left on

Refined carbohydrates include:

• white bread and pasta
• biscuits and pastries
• sweets and cakes

Which types of carbohydrates are better for my health?

Complex carbohydrates provide your body with a steady source of energy. They release sugar into your blood more slowly than sugary foods and drinks, or refined carbohydrates like white bread. This can keep you feeling fuller for longer, helping to control your appetite and maintain a healthy weight.

The ‘free’ sugars added to processed foods and drinks – like biscuits, fizzy drinks, chocolate, and cake – are best consumed only occasionally. These foods and drinks can be high in calories, raise your blood sugar, and often lack other useful nutrients.

Free sugars are also naturally present in honey, syrups, and fruit juices, so it can be confusing to understand what’s helpful or not. What’s important is to be aware of these free sugars and try to reduce your sugar intake when you can.

Processed or refined starchy carbohydrates, such as white bread, pasta, and cereals are less healthy than wholegrain options. This is because when grains are processed, fibre and other valuable nutrients are removed to make them look whiter.

How many carbohydrates do I need?

Aim to make starchy foods – ideally wholegrain starchy carbohydrates – about a third of your diet. Include things like wholemeal bread, brown pasta, or brown rice in every meal, as well as some fruits and vegetables. In general, a portion of carbohydrate for one meal should be about the size of your fist. The exact amount you need differs from person to person. It depends on many things, including how active you are. As a minimum, adults should have 130g of carbohydrates per day.

Do all bodies react the same to carbohydrates?

The way carbohydrates affect your body can depend on if you have certain conditions. If you have diabetes, carbohydrate counting becomes very important. A registered dietitian can help you with this. While you must watch your intake of sugary foods, this doesn’t mean you have to completely cut out carbohydrates. There are healthier sources of carbohydrates you can include in your diet such as fruit, vegetables, and wholegrains.

These are foods with a low glycaemic index (GI). GI is a measure of how quickly the carbohydrates in your food are digested and broken down into sugar molecules. Low-GI foods cause your blood sugar level to rise and fall slowly, so you feel fuller for longer.

See our infographic below of healthy food swaps for a lower GI diet.

Should I eat a low carbohydrate diet?

Some diet plans, such as the Keto diet and the Atkins diet, are based on reducing the amount of carbohydrates you eat. However, there’s no evidence that diets like this are any more effective than diets that focus on reducing your overall calorie intake. Diets like this can also be difficult to stick to, which can make it harder to maintain weight loss in the long-term. In addition, low-carbohydrate diets often don’t leave room for the healthy carbohydrates in fruit, vegetables, and wholegrains, which contain essential nutrients and fibre.

Carbohydrates do contain calories, but less than half the number found in fat. Of course, it’s important not to overeat any food group.

If you eat more carbohydrates than your body can burn off as energy, the excess will be converted to fat. But carbohydrates are an important part of a healthy diet. So instead of removing carbohydrates from your diet completely, focus on choosing the right kinds.