Evaluating the diet in Germany with two indices focusing on healthy eating and planetary healthy eating using nationwide cross-sectional food intake data from DEGS1 (2008-2011).

Purpose: To improve sustainability, adjustments to current diets are necessary. Therefore, limited planetary resources are considered within the healthy reference diet proposed by the EAT-Lancet Commission. The agreement with nationwide food intake was evaluated with two indices which reflect this reference and German food intake recommendations.

Methods: A healthy eating index (HEI-MON) reflecting the dietary guidelines of the German nutrition society and a planetary healthy eating index (PHEI-MON) reflecting the healthy reference diet were developed, with scores from 0 to 100. Both indices were applied to data from a nationally representative sample of the German population aged 18-79 years for which data from a 53-item food frequency questionnaire are available.

Results: Mean scores for the indices were 53 for HEI-MON and 39 for PHEI-MON. A better adherence to either guideline could be found among women, persons of older age as well as persons with higher education level. The sub-scores for HEI-MON showed high agreement with the recommendations for side dishes, fruit/nuts, (processed) meat and cereals, but low agreement with the recommendations for free sugar and vegetables/legumes. PHEI-MON sub-scores were highest for poultry, fruits and potatoes, and lowest for nuts, red meat and legumes. High scores in one index do not necessarily correspond to high scores in the other index. Individuals with more plantbased diets had higher scores in both indices, while high sugar and meat consumption led to lower scores.

Conclusions: More plant-based diets are crucial for individual and planetary health. Both indices reflect such diets which consider already health and sustainability aspects. At an individual level, the scores for both indices may differ considerably, but overall there is a huge potential in the population to adapt to a diet more in line with both guidelines.