You may have noticed the term Guideline Daily Amounts or GDAs mentioned on food labels, but what does it mean? Guideline Daily Amounts are a guide to the total amount of energy and nutrients that a typical healthy adult should be eating in a day.

These values are provided on a voluntary basis by the food and beverage and retail industries, to give context to the energy and nutrient content of foods and beverages.

By providing consumers with this information, it is hoped that they will have a better understanding of how individual products contribute to achieving an overall balanced diet. The food and beverage and retail industries derive their GDA values from international, EU and government guidelines that are based on the latest published scientific data on dietary requirements and recommendations.

However, differences have been observed between the various systems used, due to the origin of the scientific data reference and minor differences in calculation techniques. Consumers in the UK are already familiar with the concept of GDAs, following the introduction of this on pack information by many manufacturers and retailers in 1998. In continental Europe, GDAs are gradually gaining acceptance. Recently, the Confederation of the Food and Drink Industries of the EU (CIAA) proposed a harmonised industry approach to nutrition labelling across the EU, including the use of standardised GDA values. This would help to eliminate the differences between GDA values that have currently been observed. GDAs for energy and nutrientsIn general, GDAs are available for energy (calories) and the four most important nutrients that may increase the risk of developing some diet-related diseases: fat, saturated fat, sugars and sodium (or salt). GDAs for carbohydrates, protein and fibre may also be given at the manufacturer’s discretion.

Guidelines for adults are based on typical requirements for healthy men and women over 18 years of age, of normal weight and/or for weight maintenance. The energy GDA values are derived from estimated average population requirements (EAR) for energy and take account of the current activity levels and lifestyle of an average citizen, which tends to be fairly sedentary. The energy is commonly measured in “kilocalories” (kcal), also referred to as “Calories”: both expressions are equivalent and commonly used on food labels. For an average woman the energy GDA is 2000 kcal and 2500 kcal for an average man: these values are used as a reference to calculate the guideline daily amounts for nutrients. Where it is impractical to provide separate guidelines for men and women, ‘adult’ GDA values are based on GDA values for women, to discourage over-consumption. Guidelines for children have also been developed for both boys and girls. Reference GDAs for children are generally only found on labels or literature associated with products intended specifically for children.