'When you improve nutrition, you reduce violence': Psychologist Kimberley Wilson on working in Europe's largest women's prison

British psychologist Kimberley Wilson has worked with people from all backgrounds following her years working as a therapist at London's Holloway Prison, which was Europe's largest women's prison at the time. But those formative years shaped the advice Wilson gives her clients and patients to this day.

During her time at Holloway, Wilson learned about surprising links between diet, mental health and behavior in the population she worked with. Those early findings were so promising they inspired the work Wilson has done over the past decade, as well as her two books: "How to Build a Healthy Brain" (Yellow Kite, 2020) and "Unprocessed: How the Food We Eat is Fueling our Mental Health Crisis" (Ebury Publishing, 2023).

In an interview with Live Science, Wilson described her journey from those early years to her current practice, emphasizing the links between mental Health and nutrition.

Sascha Pare: You became interested in nutrition after training as a psychologist — how did food first pop up on your radar?

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Kimberley Wilson: My first proper job when I qualified was in a prison working for a charity developing and offering therapy to prisoners. The thing about women at that time [between 2008 and 2013] — and I'm going to assume it's still the same — is that, although they only made up about 6% of the overall U.K. prison population, they accounted at the time for about 50% of the self-harm that was occurring across the entire U.K. prison estate. [Recent figures show that in 2022, women prisoners accounted for 29% of self-harm incidents while making up only 4% of the U.K. prison population. And between 2022 and 2023, rates of self-harm increased by 43% in female establishments.] 

It was around that time that this replication [in the Netherlands] of a [2002 U.K.] study came out. They had taken a cohort of violent male prisoners and improved their nutritional status through supplementation [capsules containing vitamins, minerals and fatty acids]. They found that objective incidence of violence — and I say objective, so not like "How are you feeling? Do you want to punch anyone today?" but actually going through the log book at the end of the wing and counting how many infractions had happened — were 30% lower in the supplemented group compared to the placebo group.