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Carbohydrates seem to have been given a bad reputation in recent years. Say the word ‘carbs’ and for many people, stodgy food and weight gain spring to mind. But in reality, your body wouldn’t be able to function without carbohydrates.

What are carbohydrates?

Carbohydrates are compounds that your body uses for energy. They are found in almost every type of food you eat – albeit in different forms and amounts. All carbohydrates are made up of individual ‘building blocks’ or sugar molecules. The most basic carbohydrates – such as the sugar you put in your tea, or that gives your apple its sweet taste – consist of just one or two of these molecules.

Other more complex (or ‘starchy’) carbohydrates are made up of a number – sometimes hundreds – of sugar molecules joined together. These are the types of carbohydrate found in bread, pasta and rice, as well as some types of fruit and vegetables.

Fibre is also classed as a carbohydrate. However, unlike other types of carbohydrate, it isn’t usually used by your body for energy but has a number of other important functions.

Why do I need carbohydrates?

Carbohydrates are your body’s main source of energy. You use them as fuel, not only to help you walk or run, but also to keep your heart, lungs and other vital organs working properly.

When you eat any type of carbohydrate, your digestive system will break it down into simple sugars, such as glucose – the main form of fuel for your body. Glucose is then circulated in your blood to every cell in your body.

If you don’t have enough carbohydrate in your diet, your body will start to break down fat and then protein to get the glucose it needs. Protein is important for your body to be able to grow and repair itself, so using it as an energy source means there will be little left to carry out these vital functions. If you eat enough carbohydrate, you can prevent this.

Good carbs, bad carbs

There has been much misconception in recent times that carbohydrates are fattening. Of course, as with many things, it’s not good to have too much. If you eat more carbohydrate than your body can burn off as energy, your body’s glucose stores will become saturated and the excess will be converted to fat. In other words, you will start to put on weight. But carbohydrates are an essential part of a healthy diet. The key thing is to pick the right type of carbohydrates as some types are healthier than others.


Foods and drinks that are high in sugar are a major cause of tooth decay. Sugary foods, such as cakes and biscuits also tend to be high in fat, but they often don’t contain many other useful nutrients – hence the term, ‘empty calories’. They contribute to your energy intake but have little other value. Not only that, sugary foods are often very energy dense, which means they pack a lot of calories into a small volume. Even if you eat just small amounts of these foods, they can push up your calorie intake. It’s therefore best to limit your intake of sugary foods and stick to starchy foods.

Wholegrains for health

In general, the best starchy carbohydrates to go for are wholegrain foods – including wholegrain varieties of breads, pasta and cereal. Wholegrains contain a host of important nutrients that are thought to reduce your risk of heart disease and bowel cancer. When grains are processed (or ‘refined’) to make them look whiter, the part of the grain that contains fibre and many useful nutrients is removed. This means that white bread, pasta and cereals aren’t as beneficial to your health.

Wholegrains are also more likely to keep you feeling fuller for longer – as they generally take longer to digest than foods that have been processed and contain more fibre. This can help to control your appetite and help you to maintain a healthy weight.

How much carbohydrate do I need?

It’s thought that at least half the energy in your diet should come from carbohydrates. Many people are already eating enough, but it’s often the wrong type – with too much coming from sugary or refined products and not enough from wholegrain, starchy foods. Starchy foods should make up about a third of your diet. The easiest way to do this it to try to include some at every meal – and opt for wholegrains when possible.

Although it’s best to limit the sugar in your diet, this doesn’t mean cutting out fruit. The natural sugars in fruit are not as bad for your teeth as those in sugary foods and drinks, as they are held inside the cells of the fruit and only released when you chew the fruit, or if the fruit is juiced or blended as in fruit juices and smoothies. If you drink these, try to stick to one a day and drink them with a meal to reduce your risk of tooth decay.

Get into carbohydrates

Most people aren’t eating enough starchy foods. Here are some tips on how you can get good carbohydrate into your diet.

  • Cut down on refined carbohydrates if you can, swap your white bread, pasta and rice for wholemeal or wholegrain and granary versions. Also, leave the skin on potatoes when you boil them or try some homemade potatoes wedges with the skins left on.
  • Variety is the spice of life – try a bagel or tortilla wrap or wholemeal pitta as alternatives to bread. Sweet potatoes and yams make a change from plain old potatoes.
  • To get some great sources of starch and fibre in your diet, add beans and lentils to stews, casseroles and curries. You won’t need to use as much meat, so your meal will be lower in saturated fat too.


Produced by Rachael Mayfield-Blake, Bupa Health Information Team, September 2012.

For sources and links to further information, see Resources.

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  • This information was published by Bupa's Health Information Team and is based on reputable sources of medical evidence. It has been reviewed by appropriate medical or clinical professionals. Photos are only for illustrative purposes and do not reflect every presentation of a condition. The content is intended only for general information and does not replace the need for personal advice from a qualified health professional. For more details on how we produce our content and its sources, visit the about our health information page.

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