Income and affordability are often cited as major barriers for lower income groups to adopt a more sustainable and healthier dietary pattern. Reynolds et al. investigated the feasibility of shifting towards a more sustainable eating pattern by income quintiles. The study found that sustainable eating patterns can be achieved by all income groups without exceeding their current food budgets and without eliminating any foods. The authors also highlight that although the general shift needed in dietary patterns was similar across the income groups, there were clear differences in specific food shifts and tailored advice for different incomes would be needed to optimise carbon footprint reductions and nutritional quality.
Linear programming was used to identify a model diet for each income quintile that met all nutritional recommendations and was significantly lower in greenhouse gas emissions (GHGe) compared to current intakes. The linear programming identified optimum diets that deviated minimally from current eating patterns. Eating patterns and costs were based on the 2013 Living Costs & Food Survey (LCFS).
Different food shifts needed by different income groups – tailored advice essential for different income groups on how to achieve a more sustainable and healthier diet
Dietary GHGe levels were similar across all 5 income groups. However, specific foods contributing significantly to dietary GHGe differed by income group, in particular, types of meat, variety and quantity of fruit and vegetables and quantity of starchy foods.
Overall adaptations needed across all income groups were similar:
- Increase in wholegrain starchy foods, fruit and vegetables
- Reduction in animal-based foods, soft drinks and foods high in fat, sugars and/or salt (HFSS).
Differences in the types of foods consumed by income group e.g.:
- Fruit and vegetable intakes in lower income groups were less varied and overall much lower than higher income groups. Higher income groups can afford to include highly priced fruit and vegetables, whilst lower income groups would need advice on more affordable and familiar fruit and vegetable.
- Higher income groups consume considerably greater amounts of wholegrains compared to lower income.
- Types of meat: although total meat intakes were similar, lower income groups had significantly higher intakes of beef, pork, lamb and ham whilst the highest income groups had significantly higher intakes of white meat and bacon.
- Higher income groups spend significantly more on dairy compared to lower income groups.
Lower income groups can achieve healthier and more sustainable diets by spending less
The optimised diets resulted in cost savings for all quintiles: 23 pence for the lowest income group to 47 pence for the highest income groups. The reduction in costs was mainly attributable to the optimised diet being lower in energy compared to current eating habits.
Higher income groups have an advantage of being able to achieve sustainable healthy eating without as great a shift from current eating patterns compared to lower income groups.
CJ Reynolds et al. Healthy and sustainable diets that meet greenhouse gas emission reduction targets and are affordable for different income groups in the UK. Public Health Nutrition 2019;22(8):1503-1517
Avaialbe at: https://www.cambridge.org/core/journals/public-health-nutrition/article/healthy-and-sustainable-diets-that-meet-greenhouse-gas-emission-reduction-targets-and-are-affordable-for-different-income-groups-in-the-uk/8CBE9E11287F4879AA7CF343791631DF
EAT-Lancet reference diet, a long way from being affordable for developing countries
The EAT-Lancet November 2019 publication concluded that current eating patterns need to change significantly across all countries to achieve the EAT-Lancet reference diet and that substantial intervention strategies are needed to make the diet affordable. This was particularly for lower income countries where household incomes would need a significant boost alongside making low-cost nutrient dense sustainable foods readily available.
The higher cost of the EAT-Lancet reference diet for lower income countries is driven by the recommended increase in animal foods and fruit. However, the opposite is true for higher income countries such as the UK and US, which have to reduce current meat intakes and significantly increase fruit, vegetables, legumes and nuts – thus making fruit and vegetables the biggest cost contributor (31%) followed by legumes and nuts (19%). The overall cost of the EAT-Lancet diet is estimated at US $2.84 per day, which although affordable by higher income countries, the cost would exceed the income of 1.58 billion individuals from lower income countries.
Hirvonen K et al. Affordability of the EAT–Lancet reference diet: a global analysis. Lancet Glob Health 2019;8 (1):E59-E66