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Food

Cow's milk (1 liter)

Lehmänmaito (1 litra)

18.7
Truecost score
Data confidence: HIGH

Carbon, water, land from Poore & Nemecek (2018, Science) — the gold standard food LCA. Toxicity rough.

One liter of cow's milk produces ~3.2 kg CO₂e globally, mostly from enteric methane and feed production. About 8x the footprint of oat milk.

Did you know? A family of four switching just one liter of daily milk to oat saves ~1,000 kg CO₂ per year — more than a Helsinki-Stockholm return flight.
Transparent calculation

How was this number determined?

The Truecost score is calculated from absolute physical values. Each row below shows the measured value, how it was normalized, and where it comes from.

Dimension Absolute value Score 100 = Normalized Weight Weighted Confidence
Carbon Emissions 3.2 kg CO₂e 9.5 kg CO₂e 33.68 ×0.35 11.79 HIGH
Water Consumption 628.0 liters 3840 liters 16.35 ×0.2 3.27 HIGH
Land Use 9.0 m²·year 51 m²·year 17.65 ×0.2 3.53 HIGH
Waste 0.03 kg 5 kg 0.6 ×0.15 0.09 MEDIUM
Toxicity 1.0 µDALY 162 µDALY 0.62 ×0.1 0.06 LOW
Truecost score (weighted sum) 18.7

Share of your annual planetary budget

Carbon Emissions 0.34%
Water Consumption 0.16%
Land Use 0.18%
Waste <0.01%
Toxicity <0.01%
Source data by dimension

Where do the absolute values come from?

Carbon Emissions
HIGH
Poore & Nemecek (2018): dairy milk global average 3.15 kg CO₂e per liter. Includes enteric methane from cows (~40%), feed production (~25%), manure management (~20%), and processing/transport (~15%). Our World in Data uses ~3.2 kg CO₂e/L.
  • Poore & Nemecek (2018): Reducing food's environmental impacts — Science 360(6392)
  • Our World in Data (2024): Environmental impact of milks

Well-established by the most comprehensive food LCA. Range: 1.4 (best practice) to 9.0 (worst) kg CO₂e/L. Finnish dairy ~1.5 kg CO₂e/L due to efficient practices.

Water Consumption
HIGH
Poore & Nemecek (2018): 628 L water per liter of milk globally. Includes feed crop irrigation, drinking water for cows, and processing. Mostly green water (rain for feed).
  • Poore & Nemecek (2018): Science — supplementary water data
  • Mekonnen & Hoekstra (2012): Water footprint of farm animal products — Ecosystems

Varies significantly by region. European dairy: ~400-600 L. Global average: 628 L.

Land Use
HIGH
Poore & Nemecek (2018): 8.95 m²·year per liter of milk. Includes grazing land and feed crop area. Rounding to 9.0 m²·year.
  • Poore & Nemecek (2018): Science — supplementary land use data

About 10x oat milk land use. Much of this is grassland that could potentially rewild.

Waste
MEDIUM
Packaging similar to oat milk (Tetra Pak ~30g). Minor waste stream relative to upstream impacts.

Packaging is a trivial fraction of dairy's total impact.

Toxicity
LOW
Dairy farming uses antibiotics (contributing to AMR), produces manure runoff (eutrophication, nitrate contamination). Estimated ~1.0 µDALY per liter from combined health impacts.
  • Van Boeckel et al. (2019): Global antimicrobial resistance trends — Science
  • Poore & Nemecek (2018): Science — eutrophication data

AMR impact extremely difficult to quantify per liter. Nordic dairy uses relatively less antibiotics.

Comparisons

Methodology

Based on Poore & Nemecek (2018) meta-analysis of 38,700 farms in 119 countries. Global average values used. Finnish dairy approximately half the global average.

Sources