Diets need more sustainability

What is the link between cardiometabolic conditions and sustainable diets? To investigate this question, a recent study by an international research team led by Professor Ina Danquah, Hertz Chair for Innovation for Planetary Health in the Transdisciplinary Research Area “Sustainable Futures” and Director at the Center for Development Research (ZEF) at the University of Bonn/Germany, looked at diets among adult Ghanaians living in Ghana and as migrants in Europe.

What are sustainable diets?

Sustainable diets are financially affordable and have only a limited impact on the climate. At the same time, they ought to provide the body adequately with nutrients and align with people’s cultural and social habits.

The approach

First, the researchers assessed the diets of the study participants. Through a mathematical approach, they constructed dietary patterns from the data that fulfil the criteria of a sustainable diet. Next, they investigated to what extent the diet of the study participants differed from these optimum dietary patterns. This allowed an estimate of how sustainable their diet actually was. Finally, the researchers investigated whether the sustainability of the diet was associated with the development of obesity, type 2 diabetes and hypertension.

Main results

Overall, among the 2,183 participants surveyed, diets were not very sustainable. Variation in diets across the study population was small. The study shows that the diets of adults in Ghana are more sustainable than those of Ghanaian migrants in Europe. It also demonstrates that the diets of older people and people with a lower educational level are more sustainable as their calorie intake is lower.

Surprisingly, there was hardly any association between a more sustainable diet and obesity, type 2 diabetes or hypertension. The authors of the study suspect that the lack of association is attributable to the overall low level of sustainability and the low variation in the diet.

Challenges

Follow-up surveys of the participants in the study were performed during the corona pandemic. Carrying them out was particularly problematic in Ghana since people living there often have no fixed address and getting in touch with them was therefore difficult. Evaluating the results posed a further challenge, for men and women require different amounts of nutrients. Also, the usual portion sizes in Ghana differ from those in Europe, for which reason calculations had to be adjusted to sexes, the sizes of the respective portions and the locations.

Recommendations

The results show that sustainable diets in sub-Saharan Africa should consist primarily of plant-based foods. Above all, red meat and fish products could be replaced more frequently with plant foods such as pulses and whole-grain products. A little more fish and seafood could also be part of the diet. Overall, people should eat fewer foods that contain a large number of calories but comparatively few nutrients.

In the study the researchers discussed prototypes of sustainable diets, which were developed through the mathematical approach referred to above, with adults in Ghana and with Ghanaian migrants in Germany. This included questions about feasibility in everyday life, acceptability by people and cultural appropriateness. These results are to help discover whether and how these prototypes of sustainable diets can be used in future studies and health programmes.

(University of Bonn/wi)

Reference:

Clara Bergmann, Gabriel Kallah-Dagadu, Eva van der Linden, Karlijn A.C. Meeks, Kerstin Klipstein-Grobusch, Mary Nicolaou, Peter Henneman, Silver Bahendeka, Erik Beune, Charles Agyemang, Ina Danquah (2026): Sustainable diets and cardiometabolic conditions among Ghanaian adults under transition: Findings from the RODAM-Pros Cohort Study, The American Journal of Clinical Nutrition, DOI: https://doi.org/10.1016/j.ajcnut.2026.101471 

Further reading:

Rural 21 Dossier on "Food security and nutrition"