UK food prices after Brexit, with implications for poverty and health

A key driver of household food insecurity is the balance between household disposable income and food prices. In the UK in recent years, many households have relied on charitable food banks in order to eat. The UK exit of the EU (Brexit) is expected to have significant influence across the economy, including on employment, wages and prices. We use structured expert judgement to quantify food prices and associated uncertainties in a principled manner under two scenarios: a Brexit deal broadly similar to the present situation and Brexit without a deal. Here we show that consumer prices index (CPI) food prices will rise faster than previously under both scenarios (6% and 24% respectively) and that the uncertainty is significantly larger under no-deal (a plausible worst-case of 43% compared to 14% ). Under a Brexit deal, a family with two adults and two children, one at pre-school and one at primary school, buying healthy diets will suffer median increases in food costs of {\pounds}6 per week (with a plausible worst case of {\pounds}16 per week). Under a no-deal scenario, this family will suffer a median increase of {\pounds}23 per week (plausible worst-case {\pounds}45 per week). The Lancet reported that poor diet is linked to 20% of all deaths worldwide, though association with disease. Rising food prices in a condition of static UK incomes is likely to add to demand pressure on the NHS. Our results demonstrate that uncertainty analysis associated with expected changes in food costs are vital to inform policies that allow households to afford a food basket that meets their needs.