Reading Food Labels Without Getting Lost in the Numbers

A food label carries more numbers than anyone needs for a single decision. The trick is to know which one or two answer the question you actually have, and to know that the layout depends on the country you are standing in. This is a five-step way of reading a pack in about twenty seconds.

Step 1: work out which label system you are looking at

Labels are set by national or regional law, so there is no universal format. Four common ones:

In the EU, the European Commission says the required declaration covers energy, fat, saturates, carbohydrate, sugars, protein and salt. The NHS describes the same set on UK packs. US labels list sodium rather than salt, and show added sugars as a separate line within total sugars.

Step 2: find the basis – per 100 g or per serving

This is the step most often skipped, and the one that causes most confusion.

Per 100 g lets you compare two products directly, whatever the pack size. Australia’s healthdirect advises checking the per 100 g (or per 100 ml) column when comparing similar foods, so that you are comparing like with like.

Per serving tells you about the amount the manufacturer has defined. The US Food and Drug Administration (FDA) stresses that the serving size on a Nutrition Facts label is not a recommendation of how much to eat; it reflects typical consumption. If you eat two servings, every figure doubles. The NHS makes a similar point: the portion on a UK front-of-pack label may not match what you would put on your plate.

Step 3: pick the one or two lines that matter to you today

You do not need the whole panel. Decide what you are comparing. Many national guides pay most attention to saturated fat, sugars and salt (or sodium), and treat fibre as a plus. Healthdirect also suggests judging the overall picture rather than a single nutrient.

How to tell “a lot” from “a little” depends on the system.

UK: thresholds per 100 g

The NHS gives these guide values for food (drinks use different criteria):

Where a pack carries colour coding, red means high, amber medium and green low. The NHS reads this as a guide to proportion: more greens and ambers across your trolley, and red-labelled foods less often or in smaller amounts. A red square is information about the food, not a verdict on the person buying it.

US: % Daily Value

The FDA’s rule of thumb is that 5% Daily Value or less of a nutrient per serving is low, and 20% or more is high. It suggests using this to choose foods higher in dietary fibre, vitamin D, calcium, iron and potassium, and lower in saturated fat, sodium and added sugars. The percentages are based on a 2,000-calorie day used as a general reference; the FDA notes that individual needs may be higher or lower. The % column is not meant to add up to 100.

Australia: stars within a category

Healthdirect explains that the Health Star Rating is designed for comparing products within the same category – one breakfast cereal against another – and not for comparing a cereal with a yoghurt.

Step 4: glance at the ingredients list

In the UK and Australia, ingredients are listed in order of weight, largest first, as the NHS and healthdirect both explain. The first three ingredients therefore tell you what the product mostly is. The NHS notes that in the UK allergens are emphasised in the list, for example in bold. Healthdirect says that in Australia allergens must be declared even when present in small amounts.

Step 5: check the date – and what the date means where you are

Date wording is another place where countries differ. UK government guidance says that use-by dates relate to the safety of food, while best before dates relate to quality. The FDA, writing for US consumers, says a “use by” date on US food generally indicates best flavour or quality rather than safety, with infant formula as the exception. Same words, different meaning. When you are abroad, do not assume the rule you know at home applies.

What a label cannot tell you

• How much you will eat. The numbers describe the food, not your portion.
• How the food fits your week. A single product is a small part of an overall eating pattern.
• Whether a front-of-pack slogan is meaningful. Words such as “natural” or “light” need the panel to back them up. Our piece on checking a nutrition claim covers this.
• What is right for a medical condition. If you have been advised to limit salt, sugar, potassium or anything else for health reasons, ask your clinician or dietitian which line to read and what figure to look for.

Most shopping does not need any of this. Use the label when two similar products are in your hands and you want a reason to choose one. For the rest, a written list does more than label-reading ever will.