Protein
Beef vs Lentils
Lentils fix nitrogen through symbiotic bacteria and avoid livestock feed conversion. Cooked lentils supply about 9 g protein per 100 g, less than cooked beef; portions and preparation matter.
Side by side
The numbers, head to head
24 comparisons using peer-reviewed life-cycle data — greenhouse gases, land, water and protein, per kilogram of food or per 100 g of protein.
Protein
Beef vs Tofu
Tofu avoids the feed-conversion stage of livestock production. In the cited global averages, tofu has a much smaller climate and land footprint than beef-herd beef.
Drinks
Cow's milk vs Oat milk
Every plant milk beats dairy on all three environmental axes. Oat is the strongest all-rounder: low water use, temperate growing regions and no almond-style irrigation pressure.
Dairy
Dairy cheese vs Cashew cheese
Dairy cheese has a substantial footprint because milk production is resource-intensive. Cashew-based alternatives avoid dairy, but nut sourcing, added oils and processing affect their impacts and nutrition.
Protein
Chicken vs Chickpeas
Chicken generally has a lower climate footprint than beef, but pulses are lower still on average. Cooked chickpeas contain less protein per 100 g than chicken and also provide fibre.
Protein
Pork vs Tempeh
Tempeh is made by fermenting soybeans and retains protein and fibre. Pork production involves growing feed and managing manure; the impact of a tempeh alternative depends on its ingredients and processing.
Breakfast
Eggs vs Tofu scramble
Eggs sit mid-table on emissions but at the extreme end for dietary cholesterol. Tofu turned into scramble with turmeric and black salt delivers a similar plate with more protein and no cholesterol.
Fats
Butter vs Olive oil
Replacing saturated fats such as butter with unsaturated oils can lower LDL cholesterol. Olive oil contains mainly monounsaturated fat; its environmental footprint varies with farming and processing.
Protein
Lamb vs Dried beans
Lamb has a high average climate footprint and the highest land use among the foods in the cited dataset. Beans provide protein and fibre; dry beans are usually an economical staple.
Omega-3
Farmed salmon vs Algae oil
Marine omega-3s originate largely in microalgae and move through aquatic food webs. Algal supplements can provide DHA and sometimes EPA directly; contents and purity depend on the product.
Seafood
Farmed prawns vs King oyster mushroom
Some prawn farming has replaced mangroves, releasing stored carbon. Seared king oyster mushroom stems offer a seafood-like bite, but they are not nutritionally equivalent to prawns.
Sweeteners
Honey vs Maple syrup
Honey and maple syrup are concentrated sweeteners. Honey is produced by bees as food stores; some beekeepers harvest it and provide supplementary sugar feed.
Materials
Cow leather vs Plant leather
Leather production involves livestock and tanning, with impacts that depend on allocation and processing. Plant- and fungal-based alternatives vary widely in coatings, durability and fossil-plastic content.
Materials
Wool vs Organic cotton
Wool production involves sheep, methane emissions and land use. Cotton, hemp, lyocell and synthetic insulation offer alternatives, but warmth, durability and environmental impacts depend on the finished garment.
Meals
Beef burger vs Bean burger
A bean or lentil patty can have a much smaller climate footprint than beef. Added oils, binders, serving size and cooking affect its nutrition and environmental impact.
Supplements
Whey protein vs Pea protein
Some small resistance-training trials found similar gains with pea and whey supplements. Pea typically has less leucine per gram, and results depend on dose, diet and training.
Ingredients
Gelatin vs Agar agar
Gelatin is derived from animal collagen, often pig skin or cattle hides. Agar is extracted from red seaweed and makes a firmer gel with a higher melting temperature; the two behave differently in recipes.
Dairy
Dairy yoghurt vs Soy yoghurt
Soy yoghurts can contain live cultures and useful amounts of protein. Protein, saturated fat, added sugar and calcium fortification vary substantially between products.
Protein
Beef vs Seitan
Seitan is made from wheat gluten and readily takes up sauces and marinades. It is unsuitable for people with coeliac disease or wheat allergy; protein and salt content depend on the recipe.
Snacks
Milk chocolate vs Dark chocolate
Dark chocolate often contains more iron and cocoa solids than milk chocolate. Milk ingredients and flavanol levels vary with formulation and processing, so check the label.
Omega-3
Fish oil vs Flaxseed
Ground flaxseed provides ALA, but the body converts only a limited amount into EPA and DHA. Algae oil is a direct vegan source of long-chain omega-3s; supplement needs vary.
Drinks
Cow's milk vs Soy milk
Fortified soy milk is a nutritionally useful dairy alternative, with protein levels close to cow’s milk. Check calcium, vitamin D and B12 fortification; iodine is not always added.
Protein
Beef vs Mycoprotein
Mycoprotein is fungal protein grown by fermentation. Its environmental impact depends on production and processing, and some finished products contain egg white or milk.
Meals
Pulled pork vs Young jackfruit
Young green jackfruit shreds into a pulled-meat-like texture and absorbs barbecue sauce well. It is low in protein, so serve it with beans, lentils or tofu for a more balanced meal.
Questions people ask
Which foods have the highest climate footprint?
Beef, lamb and farmed shrimp have by far the highest greenhouse gas emissions per kilogram and per 100 g of protein; cheese and other ruminant dairy follow. Pulses, grains, tofu and most vegetables sit an order of magnitude lower.
Where do these numbers come from?
The figures are drawn from Poore & Nemecek's 2018 Science meta-analysis of ~38,700 farms across 119 countries, the most comprehensive life-cycle dataset available, plus the source cited on each comparison page.
Does local or grass-fed beef change the comparison?
Very little. Transport is typically a small share of food emissions, and grass-fed cattle usually emit more methane per kilogram and need more land than intensively raised cattle. The food you choose matters far more than how far it travelled.
How the comparisons work
Reading a side-by-side without being misled by it
Comparison pages are useful and easy to abuse. The figures here follow a single methodology, and the assumptions are stated so you can disagree with them precisely rather than vaguely.
Where the numbers come from
The environmental figures draw primarily on Poore & Nemecek's 2018 synthesis in Science, which consolidated life-cycle assessments from roughly 38,700 farms in 119 countries — still the largest dataset of its kind. It covers emissions, land use, freshwater withdrawals and eutrophication from farm through retail. Where a product is not in that dataset, national life-cycle inventories or peer-reviewed product LCAs are used and labelled as such.
What a global average can and cannot tell you
Food footprints vary greatly among producers. Poore and Nemecek found that even low-impact animal products typically exceed vegetable substitutes, especially for land use and emissions. That is a broad pattern, not a claim that every low-impact beef producer exceeds every plant protein producer on both measures.
Per kilogram, per gram of protein, per calorie
Choice of functional unit changes the appearance of a comparison more than any other decision. Per kilogram flatters watery foods; per calorie flatters fats and oils; per gram of protein is the fairest unit for foods eaten mainly as protein. Where these pages compare protein sources, protein is the unit, and where they compare drinks, volume is. Any table that silently switches units between rows should be treated with suspicion.
Transport is a small term
For nearly all foods, production dominates and transport is around 6% of total food-system emissions. The exception is air-freighted perishables, which is a narrow category. Locally produced beef is not lower-impact than imported legumes; the intuition that distance is the main variable is the single most common error in casual food-footprint reasoning.
Health comparisons follow different rules
Environmental comparisons rest on physical measurement; health comparisons rest on epidemiology plus a smaller number of trials. Where these pages state a health difference, they distinguish between mechanistic plausibility, observational association and randomised evidence — and note where the effect size is small enough that it should not drive a decision on its own.
Reference figures used across comparison pages
Global means, cradle-to-retail, per kilogram of product unless stated. Individual producers vary by an order of magnitude.
| Food | kg CO₂e per kg | Land m² per kg | Freshwater L per kg |
|---|---|---|---|
| Beef (beef herd) | ~60 | ~164 | ~15,400 |
| Lamb | ~24 | ~185 | ~10,400 |
| Cheese | ~21 | ~88 | ~5,600 |
| Farmed prawns | ~12 | ~2 | ~3,500 |
| Pork | ~7 | ~11 | ~6,000 |
| Poultry | ~6 | ~7 | ~4,300 |
| Eggs | ~4.5 | ~6 | ~3,300 |
| Tofu | ~3 | ~2 | ~2,000 |
| Milk (dairy) | ~3 | ~9 | ~630 |
| Legumes | ~0.8 | ~3 | ~1,250 |
| Soy milk | ~1 | ~0.7 | ~28 |
Poore & Nemecek (2018), Science · Water Footprint Network · Our World in Data
How to interrogate any food comparison
Five questions that expose most misleading charts in under a minute.
- 1
What is the functional unit?
Per kilogram, per calorie or per gram of protein — and is it consistent across every row?
- 2
Where does the system boundary end?
Farm gate, retail or plate? Excluding processing and refrigeration flatters some products substantially.
- 3
Is it a mean or a best case?
Marketing frequently cites the lowest-impact decile of animal production against the average for plants.
- 4
Who funded it?
Producer-funded LCAs are not automatically wrong, but they choose boundaries and allocations that tend to favour the sponsor.
- 5
Does it separate co-products?
Allocation between meat, leather, dairy and by-products can shift a headline number by a factor of two.
Fair and unfair comparisons
Fair practice
- Compare protein sources per gram of protein, not per kilogram of product.
- State the year, region and dataset for every figure.
- Show the spread, not only the mean, where producer variation is large.
- Separate environmental, health and ethical claims rather than merging them into one score.
Unfair practice
- Comparing best-case regenerative beef with average industrial soy and calling it representative.
- Using water totals that mix green, blue and grey water without disclosure.
- Ignoring land opportunity cost, which is where most of the carbon difference actually lies.
- Treating a single favourable study as overturning a synthesis of thousands of farms.
Questions about the methodology
Isn't grass-fed beef better?
On some measures, such as local biodiversity and soil carbon on degraded land, it can be. On emissions per kilogram it is generally worse, because slower growth means more methane per unit of meat, and it uses substantially more land.
Doesn't almond milk use enormous amounts of water?
Almonds are water-intensive per nut, but per litre of milk almond still uses far less water than dairy. The comparison that circulates online usually compares whole almonds to a glass of milk.
What about soy driving deforestation?
Around 77% of global soy is fed to animals. Soy for direct human consumption — tofu, tempeh, soy milk — is a small minority of production and is often grown outside the frontier regions.
Are these numbers valid in my country?
Directionally, yes; precisely, no. National figures vary with feed, energy mix and land history. The ranking of food categories is stable across almost every region studied.
Why is cheese so high?
It takes roughly eight to ten litres of milk to make a kilogram of hard cheese, so the dairy herd's emissions are concentrated into a small mass of product.
How often are the figures updated?
The underlying synthesis is from 2018 with subsequent refinements; where newer national inventories change a figure materially, the page notes it.
Sources
- Poore, J. & Nemecek, T. (2018). Science, 360(6392), 987–992.
- Our World in Data — Environmental Impacts of Food Production.
- Mekonnen & Hoekstra (2012). A global assessment of the water footprint of farm animal products.
- FAO (2023). Pathways towards lower emissions — global livestock assessment.