You know that eating too much sugar is bad for your waistline and teeth, but you might be surprised to learn just how much you're eating. Read on to discover the foods that contain hidden sugar, what it does to your body, and how much is too much...
See also: Young children eating twice the recommended limit of sugar a day
See also: Drinks with the most sugar named and shamed
How much sugar is too much?
There are two main types of sugar - naturally occurring sugars such as those found in milk and fruit, and added or 'free' sugars, which include table sugar and concentrated sources like honey and fruit juice.
Only 5% of your daily calorie intake should consist of 'free' sugars, according to the World Health Organisation. That means seven sugar cubes (30g) for adults and five sugar cubes (no more than 19g) a day for children aged four to six years, and no more than six sugar cubes (24g) for children aged seven to 10.
Most of us eat more of the sweet stuff than we realise because it's added to so many everyday processed foods, such as cereals, bread, sauces and soups. To make it more confusing, sugar goes by many different names – making it tricky to see from food labels exactly how much sugar a food contains.
As a general guide, table sugar is usually listed as sucrose, while fruit sugar is known as fructose. You can recognise sugars on labels because their chemical names also end in "-ose." For example glucose (also called dextrose), fructose (also called levulose), lactose and maltose. The higher that sugar/glucose/fructose (or any other name for it) appears in the list of ingredients, the more sugar the food contains.
Why sugar is so bad for us
Sugars are naturally occurring carbohydrates (and the simplest kind of carbohydrate), which get converted quickly to energy in the body. Sugar supplies energy in in the form of calories but no protein, essential fats, vitamins or minerals - which is why it's known as "empty calories".
When people eat up to 10-20% of calories as sugar (or more), this can contribute to nutrient deficiencies, as the body has to draw on the nutrients from the rest of our diet to process the sugar, which can affect our health and weaken our immunity.
Eating sugar makes your blood sugar levels rise, causing the body to release the feel-good chemical dopamine, giving you that feel-good 'high,' followed by a slump which leaves you tired, irritable and craving more sugary foods. This vicious cycle can lead to weight gain, as well as health problems, such as diabetes and heart disease.
When you eat sugary foods, the body also releases a hormone called insulin, which allows glucose (blood sugar) to enter cells from the bloodstream and also tells the cells to start burning glucose instead of fat. Eat too much sugar, however, and insulin can stop working as it should. The cells in your body can become resistant to the insulin and are unable to use it as effectively, leading to high blood sugar, which can lead to type 2 diabetes, obesity and cardiovascular disease.
Not only that, sugar is bad for the teeth, because it provides easily digestible energy for the bad bacteria in the mouth.
How to avoid hidden sugar
If you take sugar in tea or coffee, cut down the amount you have gradually until you can give up all together.
Fizzy drinks are notoriously high in sugar – a can of soft drink can contain seven teaspoons of sugar. Switch to fizzy water and low-sugar cordials instead.
Be aware that low-fat and 'diet' foods often contain extra sugar to help improve their taste and texture – so while they may be low in fat, they may be very high in sugar. Have smaller portions of the standard "full" variety, which are generally more satisfying.
Check the labels of savoury foods, such as ready-made soups and sauces. Making food from scratch at home is the best way to know what a meal contains.
Sugar in fruit – good or bad?
Many kinds of fruit are high in sugar, but these are naturally occurring and less likely to cause tooth decay because the sugars are contained within the structure of the fruit.
As well as being a good source of fibre, fruit contains lots of vitamins and minerals and so shouldn't be restricted in your diet. However, there's a good reason to stick to whole fruit.
When fruit is juiced or blended, the sugars inside are released and can cause damage to teeth.
The NHS recommends limiting fruit juice to a small 150ml glass a day, and to keep it for mealtimes to reduce the impact of tooth decay.
Dried fruit should also be limited, as it can release sugars and stick to teeth, resulting in tooth decay.