Frequently Asked Questions

Is it possible to be allergic to sugar?


Technically, no. It is not possible to be allergic to sugar (sucrose) itself, however there are incidences of intolerance to sugars, such as lactose intolerance (the sugars found in milk and dairy products).

People often refer to ‘allergies’ and ‘intolerances’ to describe a reaction to food.  They are often used interchangeably but it is important to note that they do not necessarily mean the same thing. 

Food allergies and intolerances of any kind should only be diagnosed by properly trained medical staff.  For more information on allergies or intolerance please seek advice from a health professional.

Does sugar cause diabetes?


There are two main types of diabetes, Type 1 and Type 2.  Type 2 is the one referred to here and is associated with a complex range of risk factors including being overweight.  Current scientific evidence has not established that sugar directly causes Type 2 diabetes, however there is an association between sugars-sweetened beverage consumption and increased incidence of Type 2 diabetes*.

Please see our Spotlight On…Diabetes for more information.

* SACN (2015) Carbohydrates and Health Report (accessed 20/07/15)

What is the ‘sugar-fat seesaw’?


Sugar (sucrose) usually appears in combination with other ingredients, such as fat. Research shows that diets tend to have an inverse relationship between sugar and fat intakes, for example, diets higher in sugar are likely to be lower in fat and vice versa. This effect is known as the ‘sugar-fat seesaw’*.

Did you know?: 1g carbohydrate = 4kcal whereas 1g fat = 9kcal

* Sadler MU, McNulty H, Gibson S (2015). Sugar-fat seesaw: a systematic review of the evidence. Crit Rev Food Sci Nutr. 55(3):338-56

Is sugar just ’empty calories’?


Sugar (sucrose) is a source of energy, like all carbohydrates. There are a number of reasons that sugar may be added to foods. It improves taste and shelf-life and often increases the range of foods that are eaten by making them more palatable. For example, sour or bitter fruit and vegetables, and some breakfast cereals, which can provide important vitamins, minerals and fibre, would be less palatable to some people without sugar.

It is important to eat a varied, balanced diet to ensure you are getting the right balance of vitamins and minerals. There is currently no clear scientific evidence to suggest that higher intakes of added sugars will lead to lower vitamin and mineral intakes, a theory known as ‘micronutrient dilution’1. Nevertheless, though there are a range of recommendations, current guidelines recommend that the population average intake for free sugars should not exceed 5% of total dietary energy2.

1 Rennie, K.L. & Livingstone, M.B.E. (2007).  Associations between dietary added sugar intake and micronutrient intake: a systematic review.  British Journal of Nutrition (2007), 97, 832–841
2 SACN (2015) Carbohydrates and Health Report (accessed 20/07/15)

Are added sugars metabolised differently than naturally occurring sugars?


There are many different types of sugars, including glucose (dextrose), fructose, sucrose (table sugar), lactose (milk sugar) and maltose, and these all occur naturally.  The body does not distinguish between sugars used in manufacturing or in the home, and those found naturally in fruits and vegetables. 

For example, sucrose in an apple is broken down in exactly the same way as the sucrose in your sugar bowl*.

* Schorin, M.D., Sollid, K., Smith Edge, M., Bouchoux, A. (2012).  The Science of Sugars: Part 1.  Nutrition Today, Vol 47: 3

Won’t eating sugar make me fat?


Overweight and obesity occur when there is an energy imbalance between the amount of energy taken into the body as fuel, and the amount used by the body for normal metabolism and through physical activity.  Body weight is likely to increase whenever too much food energy is consumed, or decrease whenever energy intake is less than needed.

Though there are a range of recommendations, current guidelines recommend that the population average intake for free sugars should not exceed 5% of total dietary energy*.

* SACN (2015) Carbohydrates and Health Report (accessed 20/07/15)

Do soft drinks cause weight gain?


Weight gain is caused by energy imbalance, ie, calories consumed vs energy used.  Some research suggests that it may be easier to take in extra calories from a drink than as solid food.  The Scientific Advisory Committee on Nutrition’s Carbohydrates and Health report (2015) found an effect between sugars-sweetened beverages and Body Mass Index (BMI) in children and adolescents; in particular where dietary intake is not adjusted to compensate for extra calories taken in from drinks*.  Evidence is currently limited, however, and the Report noted that further research into this area is required.

Click the link for more information about healthy eating.

* SACN (2015) Carbohydrates and Health Report – (accessed 20/07/15)

Do sugary foods cause a rush in blood sugar followed by a low?


Sugar is a carbohydrate which provides energy.  Many people think that eating sugary foods causes a dramatic rise in blood sugar (glucose) levels followed by a dip which may cause tiredness and food cravings, sometimes referred to as a ‘sugar rush’.  You may be surprised to learn that eating table sugar (sucrose) actually causes a smaller increase in blood glucose levels than eating starchy foods such as baked potatoes and white or wholemeal bread.  

Click the link for further information on glycaemic index.

Does eating sugar harm teeth?


Yes it can. Frequently eating food or drinks containing fermentable carbohydrates, which includes sugars and starches can cause tooth decay if good oral hygiene practices are not maintained.  This occurs when bacteria in the mouth react with fermentable carbohydrates to produce acid which attacks the tooth surface and removes minerals (demineralisation).  Saliva can act to replace lost minerals (remineralisation) but this is less effective if carbohydrate-containing foods or drinks are eaten too frequently.

The best way to prevent tooth decay is to brush your teeth with fluoride toothpaste twice a day, especially before going to bed, as saliva production is much lower during sleep.  You should try to eat carbohydrate-containing foods no more than four times a day*.

* PHE (2014) (accessed 14/07/15)

Is table sugar natural?


Yes.  Sucrose (table sugar) is made naturally by plants.  Plants contain varying amounts of different sugars, such as glucose, fructose and sucrose.  Sucrose (table sugar) is made up of glucose and fructose and is an abundant sugar in plants.
Sugar beet (a vegetable) and sugar cane (a grass) naturally contain particularly large amounts of sucrose, sometimes called ‘table sugar’ or simply ‘sugar’, and most commonly it is the sugar that we add to tea and coffee or use in baking.  Table sugar contains no artificial preservatives, colourings or any other additives. 

The sucrose that we add to tea and coffee is exactly the same as the sucrose found in natural fruit juices and vegetables, and is used and processed by the body in exactly the same way* (Schorin et al, 2012).

* Schorin, M.D., Sollid, K., Smith Edge, M., Bouchoux, A. (2012).  The Science of Sugars: Part 1.  Nutrition Today, Vol 47: 3

Why are food and drink products ‘reformulated’?


Food and drinks manufacturers have been working on product reformulation for many years to meet changing public health and consumer needs. This includes reducing calories, salt, saturated fat and sugars. Ingredients provide functional properties such as preservation or flavour enhancement, and when they are removed these properties must be replaced by other functional ingredients.  This is particularly the case with sugar, due to its multi-functional properties including preservation and texture.  61% of soft drinks on the market are now low calorie and no added sugar*.

For more information about reformulation please visit FDF or Leatherhead Food Research.

* British Soft Drinks Association (2015) – (accessed 3/6/15)

Which age group eats the most sugar?


According to National Diet & Nutrition Survey data, intakes of non-milk extrinsic sugars (i.e. primarily ‘free sugars’) are highest in children aged 4-18 years when considered as % contribution of total food energy.  The main sources for this age group are soft drinks, fruit juice, cakes, biscuits and breakfast cereals*.

* NDNS (2014) – (accessed 22/5/15)

White vs brown sugar – is brown sugar healthier?


No.  Both brown and white sugar (sucrose) contain 4 calories per gram of energy and are processed by the body in the same way.  Brown sugar gets its distinctive colour and differs from white sugar due to the presence of molasses, which is removed during the production of white sugar.

Is sugar addictive?


No.  The current scientific evidence and expert opinion in human studies do not support the claim that sucrose is addictive1.  Experts from the NeuroFAST Consortium2 have recently produced a Consensus opinion on food addiction stating that “there is no evidence that a specific food, food ingredient or food additive causes a substance based type of addiction.”

1 Benton, D. (2010) The plausibility of sugar addiction and its role in obesity and eating disorders. Clin Nutr, 29, 288-303
2 NeuroFAST (2015) (accessed 23/11/15)

Health professionals