Food labelling: how to read it in 30 seconds at the supermarket

What information must appear on a food label?

Under the European food information regulation, all packaged foods sold in the European Union must carry certain information [1]. Four items are especially useful when choosing what to buy:

• The ingredients list, in descending order by quantity [1].
• Allergens, emphasised within that list using a different typeface, bold or colour [1].
• The nutrition declaration, per 100 g or per 100 ml [1].
• The use-by date or best-before date [1].

The nutrition declaration always provides seven values: energy, fat, saturates, carbohydrate, sugars, protein and salt [1]. Fibre is optional [1].

If the package also gives values per serving, compare them with care because each manufacturer decides what counts as a serving. To compare two products, always use the per 100 g column.

Some packages also show a percentage of the “reference intake”. This is calculated using an average adult intake of 2,000 kcal, with 90 g of sugars and 6 g of salt per day as the labelling reference values [1]. The 6 g figure is a labelling reference, not a recommendation. For adults, the recommendation is to consume less than 5 g of salt a day. The percentage lets you compare products using the same basis; your needs may be different.

How to read an ingredients list in ten seconds

Start with the first three ingredients. Since they are listed by weight, they make up most of the product [1]. If sugar or an oil appears near the top of something marketed as healthy, that already tells you quite a lot.

Sugar has many names on an ingredients list. Glucose syrup, glucose-fructose syrup, dextrose, syrup, honey or concentrated juice all add sugar, even when the word “sugar” is not used. When three or four of these appear separately, each one falls lower down the list and the total can be harder to spot.

The second trick is to check the percentage. If an ingredient is named in the product’s name or highlighted on the package, its amount must be stated [1]. This can reveal that a pumpkin soup contains much less pumpkin than its name suggests, or that hummus advertised as containing extra virgin olive oil has very little of it.

A short list of ingredients you recognise is usually a good sign. Even so, the ingredients at the top of the list tell you the most about a product.

When is a food high in sugar, salt or fat?

Two useful benchmarks are available. The higher one comes from the UK Food Standards Agency’s traffic-light system [2]. The lower one matches the criteria a product must meet to claim it is “low in” a nutrient [2] [3]. Per 100 g of food:

• Sugars: low at 5 g or less; high above 22.5 g [2].
• Salt: low at 0.3 g or less; high above 1.5 g [2].
• Fat: low at 3 g or less; high above 17.5 g [2].
• Saturates: low at 1.5 g or less; high above 5 g [2].

Between those two benchmarks is the middle range. For drinks, which are measured per 100 ml, the thresholds are lower [2].

The back of the package is what decides whether a product fits into your shopping.

Two details can help avoid mistakes. If an older label gives sodium rather than salt, multiply the sodium figure by 2.5 [1]. The sugars figure includes all sugars, including lactose in milk and sugars naturally present in fruit [1]. That is why plain yoghurt contains a few grams of sugars even when no sugar has been added. To check for added sugar, look at the ingredients list.

The type to keep an eye on is free sugar: added sugar plus the sugar in honey, syrups and fruit juices. International guidance recommends keeping it below 10% of daily calories, with 5% as a desirable target [4]. In a 2,000 kcal day, 10% is about 50 g.

For canned foods, the liquid they are packed in can make a big difference to the salt content. We explain this in our guide to healthy canned foods and which ones to limit.

What do “low in”, “no added sugars” and “source of fibre” mean?

These are nutrition claims, and their use is regulated. Each one has a condition set out in the European claims regulation [3]:

• “Low sugars”: 5 g or less per 100 g, or 2.5 g per 100 ml for drinks [3].
• “Sugar-free”: 0.5 g or less per 100 g or 100 ml [3].
• “No added sugars”: no sugar or other ingredient used for its sweetening properties [3].
• “Low salt”: 0.3 g of salt or less per 100 g or 100 ml [3].
• “Source of fibre”: at least 3 g per 100 g; “high fibre”: at least 6 g [3].
• “Light” or “reduced”: at least 30% less than a similar product [3].

The catch is what these claims leave unsaid. “No added sugars” does not mean sugar-free. If the product contains fruit or milk, it must state that it contains naturally occurring sugars [3]. A biscuit with no added sugars may still be made with refined flour and fat. And “0% fat” on a dairy dessert tells you nothing about its sugar content.

Health claims go a step further. They link a food or nutrient to health, for example, “contributes to the normal function of the immune system”. Only claims included on the EU’s authorised list are permitted [3]. Pay attention to the wording: the claim refers to the added vitamin. The product as a whole may still contain a lot of sugar.

Can Nutri-Score help you choose?

Nutri-Score is the five-letter scale, from dark green A to dark orange E, shown on the front of some packages. It is managed by the French public health agency and is voluntary for manufacturers [5].

It deducts points for calories, saturated fat, sugars, salt and sweeteners. It adds points for fibre, protein, and fruit, vegetables and pulses. All values are calculated per 100 g or 100 ml [5].

It is mainly useful for comparing similar products on the same shelf, such as two breakfast cereals or two fried tomato products [5]. It has limits worth knowing: it does not measure the degree of processing or additives [5]. A good grade does not make a product essential, just as a middling grade does not mean you need to avoid it.

If a product does not display Nutri-Score, the nutrition table gives you the same information in figures.

What is the difference between a use-by date and a best-before date?

The use-by date is about safety. It appears on highly perishable foods, such as minced meat or packaged fresh fish, and they should not be eaten after that date [1].

The best-before date is about quality. Look for “best before”. It tells you how long the product will retain its flavour and texture if stored as directed on the package [1]. After that date, food in intact packaging that has been stored properly may still be safe [6]. Biscuits, pasta, dried pulses and canned foods usually carry this date.

The European Food Safety Authority also reminds consumers that many date instructions change once a package is opened [6]. So check “once opened, consume within” too; that is the time limit that applies in your fridge.

What we see in consultations

This is the question we hear most often at first appointments, with a phone in hand and a photo of the package. The confusion almost always starts with what is written on the front. These are the claims that cause the most confusion:

• “Natural”. This is not a claim with its own specific conditions. It may only accompany another claim, such as “naturally high in fibre” [3].
• “Homemade”, “artisan” or “grandma’s recipe”. These describe an image. Check the ingredients list to see what is actually in the product.
• “Organic”. This describes how it was produced. Organic cereals and sweets can still have sugar among their first ingredients.
• “No palm oil” or “no colourings”. These tell you what is absent, not what else is present.
• “Made with whole grains”. Check the percentage; sometimes whole grains make up only half of the cereal content.
• Turkey cold cuts. They are often leaner than fatty cured meats, although their salt content is often on the high side.

None of these products is off limits. The aim is for you to make the decision with the label in hand, rather than being swayed by the picture on the package.

The 30-second method, step by step

1. Turn the package over and read the first three ingredients.
2. Look for sugar under its other names in the rest of the list.
3. On the nutrition table, check sugars, salt and saturates per 100 g.
4. Compare them with the high and low benchmarks.
5. If you are choosing between two products, pick the one with less of the nutrient you are most concerned about.
6. Read the front of the package last, once you know what is in it.

The first week will take longer. By the third week, you will know which of the products you buy regularly pass the check without looking.