BNF responds to the documentary ‘What are we feeding our kids?’

In the documentary ‘What are we feeding our kids’, which aired on 27th May 2021, Dr Chris van Tulleken reported following a diet that was made up of 80% ultra-processed foods for four weeks to investigate the effects on his health and wellbeing.

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BNF responds to the documentary ‘What are we feeding our kids?’

In the documentary ‘What are we feeding our kids’, which aired on 27th May 2021, Dr Chris van Tulleken reported following a diet that was made up of 80% ultra-processed foods for four weeks to investigate the effects on his health and wellbeing. Over this period, he gained weight and reported a number of unpleasant symptoms including constipation, headaches and heartburn. So, what was it about this diet that might have resulted in these symptoms?

The diet Dr van Tulleken followed was, overall, a very unhealthy diet – with many foods that are calorie (energy) dense and likely to be high in salt, sugar and saturated fat such as fried chicken, meat feast pizza and chocolate pudding with very few fruits and vegetables and likely very little fibre. Thus, it is not surprising that he put on weight and did not feel well. Global dietary guidance already advises us to eat less of these types of food as we know that high consumption has a detrimental impact on health. In other words – as such a dietary pattern is unlikely to provide all the vitamins, minerals and fibre we need to be healthy, and would exceed saturated fat, sugar and salt recommendations, this is not what any nutrition or health professional would recommend. 

The term ‘ultra-processed foods’ usually refers to foods and drinks produced in factories and that can contain additives such as colours, flavours, emulsifiers or preservatives or ingredients we do not typically find at home. The definition is based purely on the level of processing – not on the nutrient content of the food.

The ultra-processed definition* certainly includes many foods that are clearly less healthy choices such as crisps, cakes, sweets, chocolate and sugary drinks and we know that we are consuming too many of these foods. But alongside all the unhealthy products consumed in the programme, the ultra-processed definition also includes foods that can be included part of a healthy diet such as wholemeal sliced bread, low fat, lower sugar yogurts, wholegrain breakfast cereals, fish fingers, or baked beans that can contribute important nutrients to the diet. In a survey we carried out earlier this year**, we found that most people didn’t realise that such foods were defined as ultra-processed and are unclear about this term and what it includes.

It is important that we limit foods high in fat, sugar and salt in the diet. But, most foods we eat are processed in some way and processed foods can help us prepare healthy meals within a limited time and budget. In our survey, 47% of people agreed that checking nutrition labels on processed foods could help them make healthier choices. Food manufacturers have a responsibility to develop healthier products, making healthy choices easier, more convenient, and affordable.

We know that there are problems with people’s diets in the UK – we’re eating too many foods high in saturated fat, salt and sugar and too few fruits and vegetables and not enough fibre. A healthy diet is all about balance, including plenty of fruit and vegetables, pulses, wholegrains, and a variety of protein-sources. However, this doesn’t mean that all processed foods have to be excluded, it’s about making healthier choices.

A study of current diets found that less than 0.1% of the population are following all current healthy eating guidance and this is having a major impact on our health, including high levels of obesity in both adults and children. We need big changes to our environment to help make it easier for people to eat well including to our food supply, healthcare system and the communities we live in.

*The term ultra-processed foods is usually based on a food classification method called NOVA which defines ultra-processed foods as ‘formulations of ingredients, mostly of exclusive industrial use, typically created by series of industrial techniques and processes (hence ‘ultra-processed’)’.

**The survey was conducted by YouGov on behalf of the British Nutrition Foundation. 2127 adults from across Britain were surveyed between 22 – 24 January 2021. The survey was carried out online. The figures have been weighted and are representative of all GB adults (aged 18+).

Links for further information on ultra-processed foods

FAQ on processed foods: https://www.nutrition.org.uk/healthyliving/resources/processedfood.html

BNF consumer survey on ultraprocessed foods: https://www.nutrition.org.uk/press-office/pressreleases/processed-foods.html

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