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Understanding the nutritional information on labels

This article demonstrates how useful the nutritional information element of labels is. RIs, traffic lights, percentage daily allowances and more.
Photograph of the width of a sandwich containing cheese, tomato, ham and cucumber being measured by a caliper
© EIT Food

Nutrition labels can help you compare products, make healthier choices and eat a balanced diet. As from December 2016, most pre-packed foods must carry a nutrition label on the back or side of the packaging [1]. There are some exemptions but they apply mainly to minimally processed foods and those with little nutritional value.

Information that’s often displayed on the back or the side of the pack

The following elements may be included on packaging:

  • Nutrients per 100 g or per 100 ml (mandatory on all packaging)
  • Nutrients per serving or portion
  • Number of portions/servings per pack (below the nutrition table)

The last two elements may have to be included in certain situations, and when given, have to meet specified requirements.

Typical Nutrition Declaration © University of Reading, Food Law

The declaration must be clearly presented and give values for energy (kJ/kcal) and six nutrients: fat, saturates, carbohydrate, sugars, protein, and salt. It may also provide information on other nutrients, such as fibre. Kcal or kilocalorie is another word for what’s commonly called a calorie. You may find this additional PDF on how to calculate the energy value of food useful.

How to use this information effectively

  • Use the nutrition information per 100g to make it easy to compare different products.
  • Remember that the labels may refer to a serving or portion size that is different to the one you consume. For example, the serving size may refer to one biscuit but if you’re eating two you’ll need to double it.
  • Use the percentages on the nutrition label to track whether you’re under or over your recommended daily allowance, or reference intake, which we’ll discuss next. [2]

Information that’s often displayed on the front of packs

The energy value and nutrient amounts may also be voluntarily repeated on the front of the pack. Food manufacturers do this to highlight information that’s important to public health and to help you, as a consumer, to make healthier choices. This nutrition information is often colour coded to help shoppers make quick decisions [3].

How to use this information effectively

The numbers on the label show you how many calories and how much fat, saturates, sugars and salt a serving of the food or drink contains, both in number of grams (g) and as a percentage of your recommended daily allowance (now referred to as Reference Intake or RI) [4].

The RIs for adults are:

Value Reference Intake
Kcal 2000
Fat 70g
Saturates 20g
Carbohydrates 260g
Total sugars 90g
Protein 50g
Salt 6g

It’s worth remembering these so you get a sense for how much of your daily allowances are provided by which foods. We’ll quiz you in the next Step!

The average woman needs 2,000 calories per day, the average man 2,500 and children fewer than 2,000 depending on their age. So the RI on a front of pack label is based on the requirements for an average woman [2].

The UK has adopted a traffic light system, developed by the Food Standards Agency, to give an at-a-glance indication of whether a product is healthy or not. Red indicates high levels of a particular nutrient per 100g, amber means medium levels and green means low levels [6].

The traffic light label below is from an ovenbaked pizza. The percentages given are are reference intake (RI) values based on the portion of food specified in the label, in this case half of the pizza. These are useful to help you track whether you’re under or over your reference intake. The pizza contains 20% of your RI for fats (as long as you only eat half) but note that of those fats, a high proportion are saturates, which are less healthy than other fats. The sugar content is only 4% of your RI.

An example of UK’s traffic light system: the label shows amounts of energy, fat, saturates, sugars and salt per portion. It also displays colour coding for fat, saturates, sugar and salt – the colours are based on quantities per 100g. The percentage of an adult’s reference intake for each nutrient is provided per portion of the food.

Who decides what levels are healthy?

The NHS has developed guidelines to help you judge whether a product is high in fat, saturated fat, salt or sugar, and if it is, how often you should eat it. For example, if you’re trying to cut down on saturated fat, eat fewer foods that have more than 5g of saturated fat per 100g.

Here is a handy food shopping card developed by NHS Tayside, to help you become familiar with the amounts of the different nutrients that are considered ‘low’, ‘medium’ and ‘high’.

Some products also display reference intakes for micronutrients such as minerals and vitamins. Minerals are inorganic substances required by the body in small amounts for a variety of functions, such as bone and teeth formation. They’re also essential constituents of body fluids and tissues. Vitamins are organic molecules that are also needed in very small amounts and are vital for ensuring our metabolism functions properly [5]. There’s a long list of these but you can look up the RIs along with the effects that eating too much of them may have.


Do you normally check on the nutritional values of your food when doing your grocery shopping? What are the key benchmarks for you, personally?

Do you think understanding your RIs will change your food buying choices? Please tell us about any changes you intend to make in the comments section below.

© EIT Food
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Understanding Food Labels

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