  Food insecurity is associated with increased risk for several health
conditions and with poor chronic disease management. Key determinants for
household food insecurity are income and food costs. Whereas short-term
household incomes are likely to remain static, increased food prices would be a
significant driver of food insecurity. To investigate food price drivers for
household food security and its health consequences in the UK under scenarios
of Deal and No deal for Brexit . To estimate the 5\% and 95\% quantiles of the
projected price distributions. Structured expert judgement elicitation, a
well-established method for quantifying uncertainty, using experts. In July
2018, each expert estimated the median, 5\% and 95\% quantiles of changes in
price for ten food categories under Brexit Deal and No-deal to June 2020
assuming Brexit had taken place on 29th March 2019. These were aggregated based
on the accuracy and informativeness of the experts on calibration questions.
Ten specialists in food procurement, retail, agriculture, economics, statistics
and household food security. Results: when combined in proportions used to
calculate Consumer Prices Index food basket costs, median food price change for
Brexit with a Deal is expected to be +6.1\% [90\% credible interval:-3\%,
+17\%] and with No deal +22.5\% [+1\%, +52\%]. The number of households
experiencing food insecurity and its severity are likely to increase because of
expected sizeable increases in median food prices after Brexit. Higher
increases are more likely than lower rises and towards the upper limits, these
would entail severe impacts. Research showing a low food budget leads to
increasingly poor diet suggests that demand for health services in both the
short and longer term is likely to increase due to the effects of food
insecurity on the incidence and management of diet-sensitive conditions.
