Prison violence is a global crisis—not just a justice issue but a profound public health and societal challenge. In the latest episode of the Stronger Minds Podcast, I ask a bold, evidence-based question:
Can improving nutrition reduce violence in prisons? And if so, why aren’t we doing it already?
The Scale of the Problem
In the UK alone, violence in prisons is escalating rapidly. According to government data, the 12 months to March 2024 saw:
A 24% increase in self-harm incidents
A 27% rise in assaults
Increased assaults on staff and deaths in custody
Meanwhile, the U.S. incarcerates nearly 2 million people, spending an estimated $182 billion annually across its sprawling detention system.
Overcrowding, underfunding, drug use, and untreated mental illness have created a pressure-cooker environment where violence is both predictable and devastating. Yet hidden beneath these familiar narratives is a less obvious, but deeply powerful factor: brain health and nutrition.
The Hidden Cost: Nutritional Deficiencies Behind Bars
The brain, particularly the regions responsible for impulse control, emotional regulation, and empathy, is the body's most nutrient-hungry organ. Unfortunately, prison diets are typically high in refined carbohydrates and low in fresh fruits, vegetables, and critical micronutrients, leading to deficits that directly impair mood, decision-making, and behaviour.
Research shows that nutritional deficiencies can:
Increase irritability and aggression
Lower impulse control
Raise systemic inflammation linked to mental health disorders
In short: poor nutrition isn't just a health risk. It's a violence risk.
The Evidence
Several gold-standard trials (randomised, placebo-controlled, and even triple-blind) have demonstrated consistent results:
Schoenthaler et al. (1997): 28% reduction in violent infractions with nutrient supplementation.
Gesch et al. (2002): 37% reduction in violentincidents in a UK prison.
Zaalberg et al. (2010): 34% drop in aggression in the Netherlands; aggression rose in the placebo group.
Raine et al. (2002): Improved impulse control and reduced reactive aggression with omega-3 and antioxidant supplementation.
Schoenthaler et al. (2023): 39% fewer rule violations among supplemented young offenders.
These are not trivial shifts in mood; these are measurable behavioural changes with serious implications for safety and rehabilitation.
The Fiscal Case
Violence in prisons costs billions globally in healthcare, insurance, staffing, compensation and legal payouts, and lost human potential. For example, injury claims from assaulted UK prison staff alone have cost taxpayers nearly £50 million since 2019.
In contrast, providing essential nutritional support to prisoners costs mere pennies per day per person.
The return on investment, both human and financial, could be enormous.
The Opportunity - Nutrition as Criminal Justice Reform
We already know that brain function is influenced by food quality. It’s time for a new conversation:
What would happen if we fed the brain inside our justice systems?
To learn more, listen to the full episode of the Stronger Minds Podcast here. Discover why it's time for justice, healthcare, and public health systems to embrace nutrition as a key pillar of reform.
Support charities like Think Through Nutrition, share this research, and challenge outdated assumptions.
Better nutrition could mean safer prisons, stronger rehabilitation, and healthier societies.