New Study Finds the Carbon Footprint of Milk Is Larger Than Official Estimates

Researchers publishing in the International Journal of Life Cycle Assessment have concluded that the climate footprint of dairy production is significantly larger than commonly reported, once emissions from damaged pastureland and degraded soils are counted. The research sharpens a long-running debate over how to tally livestock emissions and raises questions about whether current policy frameworks give a fair picture of the industry's total impact on the atmosphere.

Conventional life cycle assessments of milk focus on three main sources. Methane from cow digestion, nitrous oxide from manure and fertilizer, and carbon dioxide from feed production, transport, and processing. These figures, aggregated across a farm, a country, or the global herd, form the basis of the carbon intensity numbers that many supermarkets, sustainability labels, and national inventories rely on. They typically exclude soil carbon changes because those dynamics are harder to measure and more variable from site to site.

The new work argues that this exclusion hides a large and persistent source of emissions. Dairy operations often combine heavy grazing pressure with repeated cycles of fertilization, reseeding, and tilling to maintain forage quality. Each disturbance accelerates the decomposition of soil organic matter and releases carbon dioxide to the atmosphere. By compiling field measurements from temperate dairy regions and integrating them into a full life cycle model, the authors estimate that accounting for soil carbon loss raises per-liter emissions by a substantial margin in many systems.

The study is careful to distinguish between types of pasture management. Well-managed perennial pastures with low tillage can retain or even build soil carbon, while intensively cropped forage systems routinely lose it. The range of outcomes across real farms is wide, and the authors emphasize that their findings do not suggest every dairy operation has a hidden climate liability. Rather, they suggest that the industry average, as currently calculated, is likely too low.

The implications for policy and marketing are significant. Some national dietary guidelines, carbon footprint labels, and corporate net zero targets use dairy emissions benchmarks that would need revision under a soil-inclusive accounting framework. Voluntary carbon markets that pay farmers for soil carbon gains could also benefit from a more comprehensive baseline, because only with honest measurement is it possible to credit genuine improvement.

Dairy industry groups have responded cautiously. Representatives acknowledge that soil carbon is an important and understudied part of the picture but argue that focusing on it risks unfairly penalizing producers who already operate at the low end of the intensity range. They also point to efforts already underway to improve soil health through cover cropping, rotational grazing, and reduced tillage. The study authors agree that such practices hold promise and stress that the goal of better accounting is to reward good management, not to stigmatize an entire sector.

Consumer implications depend heavily on context. In wealthy countries where milk consumption is already high, the study strengthens the case for moderate shifts toward plant-based alternatives as one of several levers for personal emissions reductions. In parts of the world where dairy remains a crucial source of nutrition and rural income, the picture is more complicated. A climate-aligned dairy strategy cannot simply call for less milk. It must also promote production systems that protect soil carbon and reduce other on-farm emissions.

The study joins a growing body of research that pushes life cycle assessments beyond their traditional boundaries. Similar critiques have been made of beef, biofuels, and forestry products, all of which involve soil and vegetation dynamics that are hard to capture in simple input and output accounting. Integrating these dynamics is technically demanding but increasingly necessary if climate policy is to reflect real-world emissions.

For dairy farmers and policymakers, the message is not that milk is inherently bad for the climate. It is that current numbers understate what is at stake, and that the path to lower emissions runs through healthier soils as well as healthier cows. Addressing both will be central to the sector's long term future.

Efforts to build a more complete accounting framework for dairy emissions are gaining momentum across several jurisdictions. The European Union's agricultural directorate has commissioned a technical review of soil carbon measurement methods that could inform future common agricultural policy reforms. New Zealand, which has some of the most emissions-intensive dairy exports, is piloting a national farm-level reporting system that includes soil carbon change alongside methane and nitrous oxide. Canadian provinces with significant dairy industries are running similar pilots focused on quality standards and certification. Consumer research suggests that transparent disclosure can shift purchasing behavior, but only up to a point. Surveys in several European countries find that a significant minority of shoppers will pay a premium for dairy products that carry credible low carbon labels, while most continue to prioritize price, taste, and familiarity. For that reason, many policy analysts argue that voluntary labeling alone will not deliver emissions reductions at the scale required. Regulatory measures, such as carbon intensity standards embedded in trade agreements or procurement contracts, may be needed to move entire supply chains. The research also opens questions for adjacent livestock sectors. Beef production, which shares many of the same soil dynamics, is likely to face similar revisions to its carbon footprint as life cycle methods improve. Sheep, goat, and water buffalo systems have received less attention but share overlapping processes. As accounting becomes more rigorous across the sector, producers who have already invested in regenerative practices may find themselves increasingly rewarded, while those who have not may face rising compliance costs. The ultimate outcome will depend on how quickly governments, markets, and farmers adapt to a more complete picture of what it takes to produce food with less climate impact.