The sweet debate
Sugar, with its sweet taste and energy-giving properties, is an important part of our diet.
Sugar is a carbohydrate. Carbohydrates – whether you ingest them in the form of sugars or starches – are broken down in your body to form glucose. Glucose supplies the energy for everything you do: breathing, thinking, moving and digesting. Without it, your body cells, and especially your brain cells, can't survive.
There are many myths around sweet substances: for example, that sugar is bad for you, that artificial sweeteners are dangerous, and that honey is a healthier choice. However, current research tells a more complex story.
Sugar myths and facts
- Sugar does not cause diabetes. Type 1 diabetics have an insulin deficiency because of genetic factors, not diet. Type 2 diabetes is usually found in overweight people, even if they use little or no sugar.The Australian Diabetes Council advises that diabetics can enjoy a little sugar each day, provided it's part of a low-GI (glycaemic index), reduced-fat, high-fibre meal. Small amounts of sugar eaten with low-GI foods, for instance a teaspoon of sugar with oats, don't raise insulin levels significantly. However, insulin levels will rise suddenly if you eat lumps of sugar or sweets between meals. One should limit foods containing concentrated amounts of sugar, or that have a lot of added, refined sugar.
- Sugar is not the only culprit when it comes to weight gain. A person puts on weight when their kilojoule intake is more than the kilojoules they burn. The body stores all excess kilojoules as fat, regardless of whether they're derived from sugars or from other sources. A moderate amount of sugar (four to six teaspoons a day) is not unhealthy. According to dieticians and scientists, even dieters can use this much. Always make it part of a balanced diet.
- Researchers have yet to find any evidence to back the claim that sugar causes hyperactivity. Nevertheless, it's not a good idea to let children overindulge in a lot of sweet things all at once. Sugar and sweet things should make up only part of a meal or snack – not meals in themselves.
- Sugar can cause tooth decay if you eat sugary or starchy food and neglect to floss and brush your teeth twice a day with fluoride toothpaste. Limiting snacks to five times a day and brushing regularly should keep the bacteria that cause tooth decay in check. Babies and toddlers shouldn't go to sleep with a bottle of milk, formula, soft drink, fruit juice or sweet tea in the mouth. This is the main cause of tooth decay in small children.
Honey, “nature's sweetener”
- Honey looks beautiful and tastes delicious, but isn't any healthier than sugar.
- Honey (like sugar) has certain healing powers: it can stop the growth of bacteria and prevent infection; honey on a wound will help it heal more quickly. However, as food, honey has no great health benefits, as it contains few minerals and vitamins.
- For weight-loss, honey isn't any better than sugar. A teaspoon (4 g) of sugar contains 68 kj; the same amount of honey contains 64 kJ. (Often, people use as much as a tablespoon of honey in their tea, making the kilojoule intake higher.)
- The composition of honey is similar to that of table sugar, which consists of sucrose (which is made up of glucose and fructose). Honey is almost 70 per cent fructose and glucose and 30 per cent other sugars. Because of this similar composition, honey has almost the same GI as sugar, and the same effect on blood-sugar levels.
- Warning: Honey shouldn't be given to children younger than a year as it contains spores of the botulinum bacterium, which can cause food poisoning. Sterilised honey is available and safe for youngsters.
Low-kilojoule sweeteners taste a lot like sugar but are sweeter by weight. (Depending on the type of sweetener, they can be a hundred to a thousand times sweeter.)They contribute very few kilojoules to the yoghurts, cooldrinks and other products they’re added to, and are useful for diabetics and people trying to lose weight. Even though artificial sweeteners are low in kilojoules, you shouldn't use more than eight pills (or powder equalling eight teaspoons) a day. Many websites claim that the sweetener aspartame is associated with cancer. However, the European Food and Safety Authority (EFSA) has found no evidence of this. EFSA maintains that the Acceptable Daily Intake for aspartame (40 mg/kg body weight) is safe. A 2003 survey by Food Standards Australia and New Zealand (FSANZ) found that Australian consumption was well below these levels.
A sugar alcohol or polyol is neither sugar nor alcohol. It is a carbohydrate that corresponds partly to the structure of alcohol. Sorbitol, mannitol, xylitol, maltitol syrup, lactitol, isomalt and hydrogenated starch hydroxyl are common sugar alcohols. Polyols are often used in chewing gum. Sugar alcohol can also be handy for diabetics and dieters because it's only partially digested, so the body absorbs fewer kilojoules from it than from sugar. Some polyols are sweeter than sugar, allowing one to use less.
Fructose is the sugar found in fruit and vegetables. Most forms of pure fructose are manufactured from corn sugar.
Often people who want to follow a healthier lifestyle use fructose rather than sugar because fructose has a lower GI and doesn't raise blood sugar levels quite as quickly as sugar. It's also twice as sweet as table sugar, and you therefore use half as much. However, you should avoid using more than four teaspoons of fructose a day because it can upset your stomach.
Sources: Karen Protheroe and Carol Browne (dieticians); Liesbet Delport (GI Foundation); Cancer Council, Western Australia; European Food Safety Authority (EFSA); Food Standards Australia New Zealand (FSANZ)
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