Sustainable and healthy diet index (SHDI) unveils regional differences in Europe and Northern Africa: findings from...

We developed a diet quality index based on the Planetary Health Diet (PHD) to assess healthy and sustainable diets. The index was applied alongside socio-demographic characteristics in five regions across Europe and North Africa.

The Sustainable Healthy Diet Index (SHDI) was designed using existing and validated healthy diet indexes. A total of 2,210 respondents from five case study territories (CST)-Cilento (Italy), Copenhagen (Denmark), North Hessia (Germany), Kenitra (Morocco) and Warsaw (Poland)-completed a food-group frequency questionnaire. Reported consumption frequencies for 24 food groups were converted to grams to assess compliance with PHD recommendations. A higher SHDI score indicates a more sustainable and healthier diet, although the environmental and health impacts are not directly assessed but are estimated based on intake at the food group level.

Copenhagen and Warsaw showed the highest SHDI scores, indicating better adherence to the PHD. In North Hessia, males had significantly better diet quality than females (p < 0.001). In Poland, female respondents with higher income and education had significantly better diet quality (p < 0.05). Compared to national studies, some food group intakes were unexpected, for example, high legume consumption in Copenhagen and high meat intake in Kenitra. Despite the Mediterranean diet being typical for Cilento, vegetable intake there was low.

Some regions, such as Copenhagen, Kenitra, and Cilento, show beneficial eating patterns, particularly high legume intake. However, meat remains overconsumed in most CSTs. Our study highlights the need for further research to promote cultural acceptance of healthier and more sustainable dietary habits, such as increasing vegetable consumption and reducing meat intake.