Updated: Sep 1
Sugars are carbohydrates. Like all carbohydrates, they provide a source of energy in our diet. Sugar is a term that includes all sweet carbohydrates, although the term most often is used to describe sucrose or table sugar, a ‘double sugar’. The body breaks down carbohydrates into simple sugars such as glucose, that can be readily used in the body. There are several different sugars. Sugars occur naturally in some foods, such as fruit and dairy products, and are also added to a wide variety of foods. Sugar can take many different forms, including white, raw or brown sugar, honey or corn syrup. Too much sugar in the diet can contribute to health problems like obesity and tooth decay. Refined (or processed) sugar provides a quick, simple source of energy, but it doesn’t contain other nutrients such as vitamins and minerals. Sugars are popular in the processed food industry because they add taste, colour, bulk and thickness to food products. They also prevent mould forming and act as a preservative.
Sugar in moderation
A ‘moderate’ intake of refined sugar can be an acceptable part of a healthy diet. Experts define a moderate intake as about 10 per cent of the total energy intake per day. However, people who consume a lot of sugary food and drinks at the expense of more nutritious food choices, may be taking in a lot of ‘empty calories’. Adding a little sugar to nutritious grain foods, such as wholegrain bread and cereals, may encourage people to eat more of these foods by making them more tasty.
Sugar and obesity
There has been a lot of debate about the link between high sugar intake and being overweight or obese. But there is general agreement that energy (kilojoules) above the body’s needs will be stored as fat. Sugar is a form of carbohydrate and it provides the same amount of energy or kilojoules (kJ) per gram as other forms of carbohydrates found in bread, rice, pasta and fruits. One gram of carbohydrate provides 16 kJ of energy. One gram of fat provides 37 kJ. Therefore, fats in food contribute double the energy than the equivalent amounts provided by sugar.
Having too much sugar
Although sugar provides less energy than fat, it can contribute to the ‘energy density' (number of kilojoules) of foods and drinks. It’s easy to overindulge in foods, especially drinks, with high sugar content. Having too much sugar is not the only reason for obesity or being overweight, but it does add to the number of kilojoules in food. Eating too much of any food, without doing enough exercise, will cause you to become overweight.
Soft drinks are high in sugar
Sweetened drinks are heavily advertised, cheap and commonly available. In Australia, the consumption of soft drinks, which are sweetened with sugar, has increased by 30 per cent in 10 years. The standard serving size for soft drink has also increased. Ten years ago, soft drink was available in 375 ml cans. Soft drinks are now commonly sold in 600 ml bottles, which provide up to 16 teaspoons of sugar. For an average 14 year old girl, a 600 ml bottle of soft drink alone will provide more than 12 per cent of her daily energy needs. This means she would exceed the recommended energy intake from refined sugar with just one drink. Studies of children in the United States found that drinking more sweetened soft drink was linked to increasing overweight and obesity. It’s best to keep these drinks to a minimum.
Fats in sweet foods
Sugars are often found together with fats in foods like chocolate, biscuits and cakes. A high fat intake is quite likely to contribute to being overweight or obese because fat is very ‘energy dense’. It is a healthy choice to limit both the fat and the sugar content in the foods you eat. Lots of commercially produced sweet foods contain high levels of saturated fat, which will increase your blood cholesterol levels and your risk of heart disease.
Carbohydrates and glucose
Your body breaks down carbohydrates and converts them into a simple sugar called glucose. This ready form of energy is carried through the blood and delivered to every cell. The supply of glucose needs to be constant and dependable, so your body has developed a number of systems to ensure this supply. For instance, the pancreas secretes a hormone called insulin that regulates the amount of glucose in the blood. Insulin allows glucose to enter body cells. It also helps with the storage of excess glucose in the liver, which supplements blood glucose levels if they start to fall. A person with diabetes has either insufficient or inefficient insulin, which means their blood glucose levels tend to be too high.