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It is not possible to be allergic to sugar. This is a good thing because if someone were allergic to sugar, they would be unable to eat a huge number of foods, including most fruit and vegetables!

Some alternative/complementary medicine practitioners 'diagnose' an allergy to sugar using tests that may appear scientific but which in fact have no scientific basis whatsoever. Food allergies of any kind should only be diagnosed by properly trained medical staff.

For more information on allergies, go to the British Allergy Foundation's website

Diabetes is a disease caused by inadequate production, or lack, of the hormone insulin. Obesity has been highlighted as a major risk factor in diabetes development and over 80% of people with Type 2 diabetes (the most common type) are overweight. It is certainly not caused by eating too much sugar. Eating a healthy, balanced, low-fat, diet and increasing physical activity will help to prevent excessive weight gain.

Insulin is one of the hormones the body needs to keep blood sugar (glucose) levels within the narrow range required for good health. In most people, when food is consumed, blood glucose levels rise and insulin is produced to bring them back down. In people with diabetes, this insulin response is defective and, if not treated, blood glucose levels become dangerously high.

For many years, people with diabetes were told to avoid sugar. However, modern scientific research has shown that people with diabetes can include moderate amounts of sugar in their diet as part of mixed meals, without compromising blood glucose control.

Further reading and scientific references

People rarely eat sugar on its own. Adding sugar to foods improves their taste and increases the range of foods that people will eat. For example, without sugar many breakfast cereals, which provide important vitamins, minerals and fibre, would be less palatable.

Surveys have shown that vitamin and mineral intakes are rarely lower - in fact, they are often higher - in people who eat the most sugar. In any case, most people in the UK are consuming more than enough vitamins and minerals. Those who are not tend to be people who do not eat enough food overall, or who do not have a sufficiently varied diet.

Further reading and scientific references

In the 1970s it was suggested that hyperactivity in children (also known as Attention Deficit Hyperactivity Disorder or ADHD) was caused by eating too much sugar. Detailed studies, however, have concluded that there is no link between sugar consumption and hyperactivity or any other type of 'bad behaviour' or learning difficulties. Children may become over-excited on occasions where lots of sugary foods are eaten (eg birthday parties) but this is a consequence of the situation, not their sugar intake. Sugar is a normal part of a healthy diet and it is not possible to be 'allergic', 'intolerant' or 'sensitive' to sugar.

Further reading and scientific references

Eating sugar or other carbohydrates will not give you 'Syndrome X'. It is caused, in the majority of people, by over-eating and an unbalanced diet, especially too much saturated fat, and by not getting enough exercise.

'Syndrome X', or the metabolic syndrome as it is also called, is the term applied to a collection of abnormalities in body function. These include resistance to the action of the hormone insulin, fat accumulated around the waist (central obesity) and increases in other risk factors for coronary heart disease development, for example, increased levels of fats in the bloodstream and raised blood pressure. Although a number of these abnormalities will be present in affected patients, the same symptoms may not be present in everyone, for example not all patients will have insulin resistance.

Taking regular exercise, such as brisk walking, and consuming a healthy balanced diet, low in saturated fat, will improve your fitness levels and your general health, and help to prevent the development of this syndrome and its complications.

Further reading

Goop L. 2000. Genetics of the metabolic syndrome. British Journal of Nutrition, 83:Suppl 1, ppS39-S48.

Hales C.N. and Barker D.J. 2001. The thrifty phenotype hypothesis. British Medical Bulletin, 60, pp5-20.

Katzmarzyk P.T., Church T.S., Blair S.N. 2004. Cardiorespiratory fitness attenuates the effects of the Metabolic Syndrome on all-cause and Cardiovascular Disease mortality in men. Archives of Internal Medicine,164, pp1092-1097.

Reaven G.M. 1995. Characteristics of Metabolic Syndrome X. Endocrinology and Metabolism, 2(Suppl. B), pp37-42.

There are many different types of sugar, including glucose (dextrose), fructose, sucrose (table sugar), lactose (milk sugar) and maltose. All these sugars occur naturally, and all are added to certain foods during manufacture.

Most fruit and vegetables contain a mixture of glucose, fructose and sucrose

Source:Food Standards Agency (2002) McCance and Widdowson's The Composition of Foods, Sixth Summary Edition. Cambridge: Royal Society of Chemistry

Different sugars have different properties, but these properties are the same whether they are already present in food or have been added during preparation, cooking or at the table.

There is no difference between the sucrose in a banana, the sucrose in a cake, or the sucrose added to a cup of tea.

Further Reading

Food and Agriculture Organisation of the United Nations & World Health Organisation. 1998. Carbohydrates in Human Nutrition. Report of a Joint FAO/WHO Expert Consultation. FAO Food & Nutrition Paper 66