How portion sizes are leaving consumers in the dark

Portions of chocolate cake

It’s not just what you eat but how much of it that matters for your health. But without clear guidance to help us, most people are left confused, as Sarah Brealey reports.

Do you know what a portion of cornflakes should look like, or how many people a big ‘family-size’ bar of chocolate should feed? Most people don’t. In fact, nearly four out of five people the BHF surveyed* had no idea what the manufacturer’s recommended portion size of cornflakes was. When we asked them to pour their normal serving of cornflakes, nearly nine out of ten poured out more than the 30g which the manufacturer said was a portion. The average portion served out was 44g – nearly 50 per cent more.

As for a 200g bar of milk chocolate, it should give eight portions according to the on-pack information. But only 10 per cent of people actually knew that. Nearly three-quarters thought it would feed four adults or fewer, with a third of people thinking it would be the right amount for one or two people. If they ate this amount in one sitting, it would mean they were consuming much more sugar and fat than if they stuck to the suggested portion guidance.

"Knowing what is an appropriate portion size is vital to maintaining a healthy weight"

People need to be able to make healthy choices in order to reduce their risk of cardiovascular disease and avoid gaining weight – which is why the BHF has been campaigning for clearer food labelling. But to properly understand food labels, you need to know whether you’re eating more than the suggested serving size or not; knowing what is an appropriate portion size is vital to maintaining a healthy weight.

This is particularly important with energy-dense foods, such as chocolate and cake, where even a small increase in portion size can make a big difference to the amount of calories and fat you are consuming. The last government information on portion sizes was about 20 years ago. Since then, food retailers have been using different approaches to define the portion sizes of their products. This has led to differences between brands of the same food product, making it difficult to make comparisons when shopping.

Our hard-hitting new report on portion sizes calls for new government guidance that is more consistent and representative. We want companies to give realistic, easy-to-understand portion sizes on food labels, and to describe portion size in other ways than by weight, which would make it clearer. We know that the public agrees. Two-thirds of the consumers we interviewed think the Government and food industry should be doing more to make it easier for people to understand portion sizes.

What consumers said

Many consumers in our focus groups commented that they have difficulty reading and/or interpreting nutritional information on packs.

Comments included:

"They should make it much clearer what the portion size is that the nutritional information refers to."

"I always thought the calorie and fat content corresponded to the whole packet. I didn't realise it was only for a's a bit misleading."

"Some of them are really difficult to work out. Some are grams, some are portions, some per unit. You need a calculator....sometimes I just give up."

"It's too complicated at the moment. There are too many different systems. There should be a single standard to make it easier to understand."

*= Based on research with 140 people, January-February 2013

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