Diets play a crucial role in shaping both personal health and the broader environmental area. Unbalanced eating habits, characterised by low fruit and vegetable consumption, excessive intake of red and processed meats, and overconsumption of calories, contribute to some of the most significant health challenges worldwide. These dietary patterns are linked to chronic conditions such as cardiovascular diseases, cancer, and type 2 diabetes, which demand costly medical interventions and place immense strain on healthcare systems.

The burden of chronic diseases caused by poor dietary habits is significant. Cardiovascular diseases, including heart attacks and strokes, are among the leading causes of death worldwide. Unhealthy diets high in saturated fats, cholesterol, and sodium contribute to elevated blood pressure and high cholesterol levels, increasing the risk of these conditions. Cancer, another major health concern, is often linked to dietary factors. High consumption of red and processed meats has been associated with increased risks of colorectal and stomach cancers. Additionally, diets rich in refined sugars and unhealthy fats contribute to obesity, which is a major risk factor for numerous cancers.

Type 2 diabetes, another condition heavily influenced by diet, has reached epidemic levels in many countries. Diets high in processed foods, refined carbohydrates, and sugary beverages increase insulin resistance, leading to the development of diabetes. This chronic disease not only affects an individual’s quality of life but also places a tremendous financial burden on healthcare systems due to the high costs of treatment and management.

Beyond personal health, dietary choices also have profound environmental consequences. The global food system is a major contributor to climate change, responsible for extensive land use modifications, freshwater depletion, and excessive fertiliser application. Agriculture accounts for approximately 25% of global greenhouse gas emissions, with livestock production being a significant contributor. The production of animal-based foods requires vast amounts of land, water, and feed, leading to deforestation, biodiversity loss, and soil degradation.

Additionally, the use of fertilisers and pesticides in large-scale farming practices results in water pollution and depletion of natural resources. Excessive irrigation in agriculture has led to water scarcity in many regions, affecting both ecosystems and human populations. The transition to more plant-based diets presents an opportunity to mitigate these environmental impacts. By reducing reliance on resource-intensive animal products, individuals and societies can decrease greenhouse gas emissions and promote sustainable resource use.

National Dietary Guidelines

Governments establish food-based dietary guidelines (FBDGs) to provide recommendations for healthy eating and influence national nutrition policies. These guidelines shape food environments, impact public health outcomes, and carry significant implications for global sustainability efforts. However, many existing FBDGs fail to align with environmental objectives outlined in agreements like the Paris Agreement and the Sustainable Development Goals.

FBDGs serve as official recommendations designed to promote public health by providing guidance on nutrient intake, portion sizes, and food group consumption. They influence consumer choices, food industry practices, and agricultural policies. However, despite their importance, many national FBDGs focus primarily on health and nutrition without incorporating environmental sustainability considerations. This gap highlights a missed opportunity to promote dietary patterns that are both health-conscious and environmentally sustainable.

Current dietary patterns in most nations are neither health conscious nor environmentally sustainable. A shift towards adherence to national FBDGs could lower premature mortality rates caused by non-communicable diseases. However, the environmental benefits of FBDG adoption vary widely; while some guidelines help curb greenhouse gas emissions, most fall short of aligning with broader global sustainability goals.

Comparing Dietary Recommendations

Different organisations provide dietary recommendations, but their approaches to health and sustainability vary. The World Health Organisation (WHO) offers guidelines that share health benefits with FBDGs but lack explicit environmental considerations. In contrast, the EAT-Lancet Commission encourages plant-based diets, which offer substantial advantages in both health and sustainability.

WHO dietary guidelines focus on reducing the risk of diet-related diseases by recommending balanced nutrition and limited intake of harmful substances such as trans fats, added sugars, and excessive salt. However, these recommendations do not explicitly address environmental concerns associated with food production and consumption.

The EAT-Lancet Commission, on the other hand, provides a comprehensive framework that integrates both health and environmental sustainability. Their recommendations advocate for a primarily plant-based diet, with limited consumption of red meat, dairy, and processed foods. This approach significantly reduces the environmental footprint of food production while improving public health outcomes. By prioritising plant-based foods such as whole grains, legumes, fruits, and vegetables, the EAT-Lancet diet aligns closely with both nutritional needs and ecological preservation.

A reformation of FBDGs and WHO dietary recommendations could enhance their impact on public health while ensuring environmental sustainability. Integrating stronger plant-based recommendations would improve both outcomes, creating a more balanced approach to nutrition and conservation.

Shortcomings of Current Dietary Guidelines

Most national dietary guidelines suggest reducing red meat intake, yet the recommended limits are generally more lenient than those proposed by the EAT-Lancet Commission, which advises only one serving per week. Additionally, high dairy consumption recommendations in many guidelines exacerbate environmental concerns, whereas EAT-Lancet suggests moderating dairy intake to minimise its ecological footprint.

Excessive energy intake, particularly from sugar and staple crops, exacerbates both health issues and environmental degradation. Overconsumption of sugar-laden products leads to obesity, metabolic disorders, and increased risks of cardiovascular diseases. Staple crops such as wheat, rice, and maize dominate global food production, often at the expense of more diverse and sustainable food sources.

Furthermore, many FBDGs fail to provide clear guidance on plant-based protein sources, such as legumes, nuts, and seeds. Less than half of national dietary guidelines present plant and animal proteins together, and critical messages regarding nuts and seeds are frequently omitted. These gaps highlight the need for more comprehensive and balanced nutritional recommendations.

Strengths and Limitations of Research on Dietary Guidelines

A comprehensive quantitative assessment of 85 FBDGs was conducted to evaluate their health and environmental impacts. A standardised coding method allowed researchers to convert qualitative dietary recommendations into measurable indicators. The study extended sustainability evaluations beyond greenhouse gas emissions to include land use, water consumption, and fertiliser application.

Comparisons between national FBDGs and global dietary frameworks, such as those from WHO and EAT-Lancet, provided valuable insights into alignment gaps and opportunities for improvement. However, the study acknowledged certain limitations, including potential confounding factors in health risk assessments and challenges in quantifying qualitative dietary recommendations. These limitations highlight the need for continued refinement in dietary research methodologies.

Policy Recommendations for Sustainable Diets

To support global sustainability goals, FBDGs must become more ambitious and incorporate stronger environmental considerations. Countries lacking dietary guidelines should develop evidence-based policies aligned with WHO and FAO recommendations to ensure both health and ecological balance. WHO’s dietary guidelines also require further detail to optimise their impact on both human well-being and environmental sustainability.

Policymakers can facilitate the adoption of improved FBDGs by implementing targeted health promotion programs, establishing public procurement policies that align with dietary recommendations, and fostering policy coherence across government sectors such as agriculture and food regulation. Economic analyses suggest that progressive dietary shifts could yield financial benefits equivalent to 10–25% of national GDP, justifying increased investment in health promotion initiatives.

Conclusion

Dietary choices are intricately linked to both human health and environmental sustainability. Current dietary patterns contribute to the global burden of chronic diseases while placing immense strain on natural resources. National FBDGs play a vital role in guiding healthier food consumption habits, yet many fail to incorporate sustainability considerations. Aligning dietary policies with scientific evidence and global environmental objectives is crucial for creating a more sustainable future. By encouraging plant-based dietary recommendations and implementing policies that support healthier food environments, societies can significantly reduce the incidence of diet-related diseases while mitigating environmental degradation. A concerted effort from governments, policymakers, and individuals is necessary to drive this transition towards a healthier and more sustainable world.

Reference

Springmann, M., Spajic, L., Clark, M. A., Poore, J., Herforth, A., Webb, P., Rayner, M., & Scarborough, P. (2020). The healthiness and sustainability of national and global food based dietary guidelines: modelling study. BMJ (Clinical Research Ed.), 370, m2322. https://doi.org/10.1136/bmj.m2322