This is the text of a 6-minute talk I gave at a conference on Childhood Anxiety at Sussex University.
As a Chinese medicine practitioner, I was taught that when considering disease or dysfunction, we should identify the branch i.e. the manifestation/symptoms/presentation, and the root i.e. the cause.
Clinically, it is usually necessary to address both, since if the root cause is ignored, treatment can be ineffective.
Childhood anxiety is multifactorial. I asked Claude AI and it came up with a host of biological, psychological, environmental, social and developmental factors. But one thing it didn’t mention is diet, which is what this talk is about.
Childhood anxiety is on the rise globally, but the United Kingdom is in the worst-performing group of wealthy nations in virtually every measure of child and adolescent mental health.
Coincidentally, UK children also have the equal worst diets in the world – along with the USA – in terms of consumption of ultra-processed foods (UPFs) which now make up around two thirds of their diet.
UPF’s are industrial formulations with little or no real food content, and should really be called food-like substances. They are especially designed to be what is called hyper-palatable, polite words for addictive addictive.
Key markers include ingredients not found in a domestic kitchen: emulsifiers, stabilisers, flavour enhancers, artificial colours, sweeteners, humectants, anti-foaming agents
Why is this important?
A 2026 systematic review of 20 recent studies found a clear association between child and adolescent consumption of UPFs, and mental health problems such as anxiety, depression, irritability, sleep disturbances and suicidal ideation.
A 2026 cohort study of over two thousand Canadian children found that as children ate more ultra-processed foods, they faced increasing risk of emotional and behavioural problems, and that replacing just 10% of UPF calories with minimally processed real food, lowered children's behaviour problem scores.
Other studies show that early exposure to UPFs is associated with increased ADHD symptoms, and that when UPFs are replaced with real food, children have a reduced likelihood of an ADHD diagnosis.
Finally it seems that a high UPF diet can reduce hippocampal volume by five percent – leading to impaired stress regulation, impair neurodevelopment and lead to lifetime cognitive deficits and susceptibility to mental health problems.
Why might UPFs cause problems
There are many factors but probably the most important is disruption of the microbiome and the gut-brain axis. UPF’s not only do not provide the fibre essential for a healthy microbiome, but they also alter the microbiome in ways that disturb synthesis of neurotransmitters such as serotonin and BDNF (brain-derived neurotrophic factor) which supports the growth and maintenamce of neurons. Emulsifiers in UPFs appear to be especially harmful to the microbiome.
So what’s the solution
We need both local and national interventions.
Locally, I have listed a range of organisations that are working to provide access to affordable, real food for children in the Brighton & Hove area.
In an ideal world, we’d be feeding our children organically grown food. Not only is it free from pesticide residues, but it is higher in nutritionally important antioxidants and polyphenols. And of course it is kinder to soil and environmental health.
Nationally, we need to wrest control of our nation’s food out of the hands of multinational companies whose primary interest is profit, not health.
The closer we look, the more corruption we find. Food corporations and trade associations met with DEFRA ministers 40 times more often than food NGOs whose primary interest is healthy food and sustainable agriculture. The Food & Drink Federation – whose members include Unilever, Mars and CocaCola -help determine government food advice and regulations. The food industry funds research favourable to themselves, and sets up and funds consumer groups to lobby on their behalf. They obfuscate the relationship between their products and the nation’s health, and vehemently oppose legislation that might curtail them. They have an equally toxic financial relationship with the media – especially the right-wing media who cry ‘nanny state’ at any proposals to regulate the industry.
It is no exaggeration to say Big Food is harming our children, injuring our health and shortening our lives, and our spineless governments are in their pockets and shamelessly refuse to act on our behalf.
• Georgiou A et al. Ultra-Processed Foods and Mental Health in Children and Adolescents: Evidence from a Systematic Review. Nutrients. 2026 Mar 12;18(6):899.
• Kavanagh ME et al. Ultraprocessed Food Consumption and Behavioral Outcomes in Canadian Children. JAMA Netw Open. 2026 Mar 2;9(3):e260434.
• Barański M et al. Higher antioxidant and lower cadmium concentrations and lower incidence of pesticide residues in organically grown crops: a systematic literature review and meta-analyses. Br J Nutr. 2014 Sep 14;112(5):794-811.
