10 tips for understanding food labels

Understanding food labels

Supermarket shelves are full of foods and drinks, many of them making claims that sound healthy. Hannah Elliott explains how to use back-of-pack food labels to make healthy choices.

Food labelling can help us make an informed decision when shopping, but understanding the labels can feel difficult. While colour-coded front-of-pack labelling is a simple way to decode a nutrition label, not all manufacturers use this system.

Back-of-pack information can still give you the same information, and can also provide more detail about the product’s nutritional content and the ingredients inside.

Here are 10 easy tips to help you read back-of-packet labelling:

1. Read the ingredients list

Most pre-packaged foods have an ingredients list on the back of the packet. Everything that goes into your food will be listed in weight order from biggest to the smallest. So if the first few ingredients contain saturated fat - like cream, butter, fatty meat or cheese - or sugars, whether white or brown sugar, syrups or concentrated fruit juice, it’s worth bearing in mind that these make up the largest proportion of the food.

Ingredients that appear further down the list will be added in small quantities, but that doesn’t always make their impact insignificant. Vitamins and minerals added to some breakfast cereals, for example, can make a positive impact on our diets, while even small amounts of salt can make a significant contribution to our maximum of 6g a day.

2. Check out the nutrition information

The most important ones to look at are total fat, saturated fat, sugar and salt – these are the “big four”

Using the per 100g column on the nutrition information table (instead of per portion) is the fairest way to compare products nutritionally, because otherwise it can be hard to tell whether the differences you see are due to a different portion size rather than the actual content of the product.

The most important ones to look at are total fat, saturated fat, sugar and salt – these are the “big four” that can affect our weight and blood pressure, contributing to our risk of coronary heart disease and stroke. But you can also compare other nutrients to make healthier choices, including the proportion of unsaturated fats (the healthier kind of fats) and fibre.

3. You don’t need to calorie count

Calories (kcal) or kilojoules (kJ) are measures of how much energy is in the product. As a guide, women need around 2000 calories a day and men need around 2500 calories. But the exact amounts needed by individuals will vary, and children’s needs will vary even more.

Constant calorie counting isn’t necessary, but it’s good to be aware which foods are high-calorie, and that this can vary between the same type of products. Get in the habit of checking the energy content of the products you eat - per portion information may be more useful that per 100g, but do check how the manufacturer’s portion compares with the amount you actually eat.

4. Look at the type of fat, and how much

SalamiFat has a lot of calories and it’s important to check whether the fat is saturated or unsaturated. Unsaturated fats, found in foods like avocado, nuts, seeds, oily fish and vegetable oils, are better for your heart health than saturated fats, found in butter, fatty meats, pastry, biscuits and cakes. Too much saturated fat can increase our cholesterol, which increases risk of coronary heart disease.

Saturated fat should be listed on the nutrition label, as well as the total fat. 

Check the nutrition information per 100g to see whether the fat content is high, medium or low:

Low fat means: 3g or less per 100g

High fat means: 17.5g or more per 100g

Low saturated fat means: 1.5g or less per 100g

High saturated fat means: 5g or more per 100g

5. Beware of reduced-fat claims

Reduced-fat or low-fat versions of foods aren’t always the healthiest options. Sometimes manufacturers replace fat with sugar, which isn’t a healthier choice. So read the nutrition information to compare sugar and fat content on the original and the reduced-fat product.

Reduced-fat or low-fat versions of foods aren’t always the healthiest options

It’s worth checking salt too, as “low-fat” or “low-sugar” options can be higher in salt. If the “lower fat” version is not much lower in energy (kcal), it might be better to simply have a smaller amount of the original product.

6. How to spot sugar on food labels

Free sugars include all sugars that are added to foods, as well as sugars in fruit juices. Sugars are added for many reasons, including for preserving and flavouring. Be alert, as sugar can sometimes be disguised under other names.

Names for sugar include:

  • Honey
  • Syrup
  • Nectar
  • Molasses
  • Fruit juice concentrate
  • Anything ending in ‘ose’ such as fructose, glucose, dextrose and maltose. 

If it’s listed on the ingredients list then it’s added sugar, however natural it sounds.

Low sugar means: 5g or less per 100g

High sugar means: 22.5g or more per 100g

7. Don’t rule out naturally occurring sugars

No-added-sugar muesliSome foods may be high in sugar but the sugar is naturally occurring, for example from fruit or milk products. This is less of a problem as the sugar is natural and will come with other nutrients, such as fibre or calcium.

So check the ingredients list and if you’re sure that there’s no added sugar (for example a no-added-sugar muesli which contains dried fruit may still be high in sugar) then there’s not too much to worry about.

The sugars in unsweetened fruit juice are naturally occurring, but the fibre has been removed from the whole fruit and because one glass contains the juice of several fruit, it’s relatively high in energy. As the sugars are not contained within the structure of the food, they’re also free sugars. So it’s recommended we have no more than one 150ml portion of juice per day.

8. Beware of salt

Salt is added to many everyday foods, including things you might not think of as being salty like bread, cakes and biscuits, so always check the label.

Too much salt can increase your blood pressure over time, which can increase the risk of developing heart disease and stroke. Most of us consume more than the recommended maximum of 6g per day - which is equivalent to a teaspoon.

Salt content is labelled on most foods and for a food to be low in salt it needs to contain 0.3g or less per 100g (or 0.1g sodium). Watch out, because some products label sodium instead of salt – you need to multiply the sodium amount by 2.5 to work out the salt content. To confuse the issue even more, sometimes the sodium is listed in milligrams instead of grams.6g per day of salt per day

Low salt means: 0.3g or less per 100g (or 0.1g sodium, or 100mg sodium)

High salt means: 1.5g or more per 100g (or 0.6g sodium, or 600mg sodium)

9. Know your portion size

The nutrition information per portion will be on the back-of-packet label and on the front of packet label if there is one. The portion size will be the manufacturer’s recommendation and portions can vary between brands.

Be aware that the portion size might be smaller than yours, which means that even if a product looks healthy, if you have more than this amount, you may end up consuming more calories, saturated fat or salt than you realise. 

10. Not everything has a nutrition label

Not all foods have to have back of packet labelling. Exemptions include fresh fruit and vegetables that haven’t been peeled or cut, herbs and spices, tea, coffee, flours, some vinegars and any drink with an alcoholic strength above 1.2%.

We’re all advised to eat at least five portions of fruit and veg each day, but alcohol, on the other hand, can have damaging effects on your health as well as adding sugar and calories to our diets.

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