Degrowth in the clinical laboratory: A key step towards integrating planetary health into the healthcare system

Healthcare contributes around 5-10% of global carbon emissions, alongside other pollutants, through utilization of over-stretched planetary resources. This creates a paradox in which efforts to protect health also generate risks to population health by contributing to the decline of planetary ecosystems- the foundation for health on which the healthcare system operates. This unsustainable cycle demands an urgent, unified front across all domains of clinical practice. Laboratory medicine, as a key entry point in the patient diagnostic pathway, is well-positioned to lead the required transformative change. While concepts such as sustainability and stewardship have been used interchangeably to rationalize resource use, the time has come to advance toward a model of 'degrowth' in the diagnostic laboratory. In healthcare, degrowth aims to minimize environmental harm by deliberately shrinking the consumption of unnecessary resources, particularly those from diagnostic and therapeutic interventions, without compromising patient outcomes. Diagnostic laboratories can support degrowth activities directly by adopting 'green laboratory' practices that include consuming less energy, minimizing waste (especially of reagents and non-recyclables) and optimizing test utilization by curbing low-value or unnecessary testing. They can also make an indirect impact by helping shift healthcare culture through shaping clinical guidelines using a degrowth lens, applying an environmental impact assessment whenever a new test is developed and advocating for sustainability declarations in publications that present new diagnostic approaches or technologies. When supported by effective stewardship programs, laboratories can serve as gatekeepers of diagnostic information and play a powerful role in aligning clinical decision-making with environmental responsibility. By embracing principles of degrowth in laboratory medicine, we have a chance, as well as a duty, to influence healthcare practices towards more ethical and environmentally responsible choices.