Which Milks Are Really Sustainable? Joseph Explores...


Let’s hit you with a hard fact before we really launch into this article. If you put cow’s milk in your coffee, that milk will, on average, account for around two-thirds of the total carbon footprint of the drink. Astounding, right? Your eco-friendly kettle and fairtrade coffee beans aren’t going to make much of a dent in this figure. A coffee without cow’s milk has around 21g of CO2e, but add a splash of milk and it shoots up to 53g. Order a milk-rich latte and the carbon footprint skyrockets to 340g (source).

There’s good news to support this fact. Non-dairy milk alternatives offer a much lower carbon footprint, despite requiring more processing. Read on to find out what alternatives exist, and what hopes for a sustainable milk-splashing future they offer.

Hold up, hold up, what’s wrong with cow’s milk again?

If you haven’t heard about the massively damaging effects of the dairy industry, we don’t want to alarm you too much, but it’s a pressing environmental issue. Documentaries like ‘Rotten’, ‘The Milk System’ and ‘Cowspiracy’ offer a much better insight into this damage than we could ever hope to present in one article. 

Here are some of the main facts to digest:

  • There are 270,000,000 dairy cows in the world, each producing an average of 37kg of waste per day
  • Cow waste produces 50x more nitrogen than human waste
  • Cows drink up to 150 litres of water per day
  • The contribution that dairy makes to our diet is not relative to the amount of physical space and earthly resources that it consumes
  • Cow milk production is intensive on freshwater, land, soil, and greenhouse gas emissions
  • The main products are ice cream, butter, yoghurt, cheese, and of course, milk, all producing large amounts of packaging waste


Facts based on one 200ml glass of cow’s milk per day:

  • 229kg annual carbon footprint
  • 585 road miles equivalent
  • Same energy used as heating a home for 36 whole days
  • Over 45,700 litres of water used in production (high)
  • 2 tennis courts worth of land space!

Which ‘milk’ offers the best alternative?

Right now, the alternative milk market is dominated by two main players, rice milk and soy milk, with two further alternatives picking up the pace in the form of oat and almond milk. 

These four ‘pretenders’ must contend with a global industry that has been around for millennia. Despite the accumulative popularity of cow’s milk, millions of people have already switched over to alternative forms of milk. So, let’s explore these types of milks further and see which is the most promising for coffee drinkers.

Rice milk

Facts based on one 200ml glass of rice milk per day:

  • 86kg annual carbon footprint
  • 219 road miles equivalent
  • Same energy used as heating a home for 13 whole days
  • Over 19,500 litres of water used in production (high)
  • The lowest land usage of non-dairy milk
  • Texture and taste arguably most similar to cow’s milk

Soy milk

Facts based on one 200ml glass of soy milk per day:

  • 71kg annual carbon footprint
  • 182 road miles equivalent
  • Same energy used as heating a home for 11 whole days
  • Only around 1,800 litres of water used in production (lowest)
  • Nutritional value most similar to cow’s milk
  • Requires a lot of land and pesticide use - also responsible for large parts of Amazonian deforestation

Almond milk

Facts based on one 200ml glass of almond milk per day:

  • 51kg annual carbon footprint
  • 130 road miles equivalent
  • Same energy used as heating a home for 8 whole days
  • Over 27,000l of water used in production (highest)
  • Typically grown in regions that are prone to drought, for example, 80% of the world’s almonds are grown in drought-plagued California
  • Lowest emissions and land use don’t compensate for the incredibly high water-use
  • Almond milk doesn’t contain as much almond (2%) as people think, and it offers low nutritional benefits

Oat milk

Facts based on one 200ml glass of oat milk per day:

  • 65kg annual carbon footprint
  • 168 road miles equivalent
  • Same energy used as heating a home for 10 whole days
  • Only 3,500l of water used in production (low)
  • Naturally fights cholesterol
  • Requires more land for production than soy, rice, or almond milk
  • Low in protein, but incredibly creamy and a great texture


Looking at the data above, soy and oat present the most sustainable milk alternatives. Let’s dig deeper.

Is soy milk a possible saviour?

In Asia, soy milk has been the market leader for 13,000 years and counting. Cow’s milk is a fairly new concept to the Asian diet, with a disproportionate amount of Asians being lactose intolerant. As a staple crop, a good source of protein, and being cheap to produce, it’s naturally the winner on this side of the world. In Europe, we mainly use soy for animal feed, but currently, the whole continent only grows 3% of what it needs and imports the rest, to the tune of 30 million tonnes per year. All of this transportation doesn’t help soy’s cause. Soy farmers are also responsible for large amounts of deforestation and using genetic modification.

Does oat milk hold the answers?

A high iron content has made oat milk good for those who suffer from anaemia, and as mentioned earlier, it also helps to battle cholesterol due to the fibre and protein content. It’s high in calories and carbs too, which is either good or bad depending on your goals. Oat milk is naturally sweet, making it a great option for coffee drinkers, and it can also be frothed to help with coffee art. 

As for sustainability, research has shown that the three major oat milk producers all use different methods of production, making it hard to gather data about production emissions. Another problem with oat milk is that it fails to meet up to the nutritional value of cow’s milk (not a problem for coffee drinks perhaps) meaning it typically has to be fortified with other nutrients - this makes measuring the environmental impact even more difficult (it’s worth noting that oat milk is still more nutritional than almond milk but less so than soy).

The largest European and North American producer of oat milk has proven 80% lower greenhouse gas emissions and 60% less energy used in production, as well as requiring 80% less land than dairy farming. This company has stopped their suppliers from using glyphosate on their crops, but competitors have not guaranteed the same. 

Which non-dairy milk wins our badge of approval?

Actually, all of them. In a sense, they are all more sustainable than cow’s milk. There are some downsides to each, but overall they offer hope for the future. If we had to pick one, it would be oat milk, especially once we’ve taken into consideration the water, energy, land, transport, ease of growth, what plants do for the environment, the texture and the taste. Oat milk has been available in Europe for decades, but it has seen a real resurgence in recent years and it’s possible that it will now kick on to compete with cow’s milk in greater measure.

What about the other alternatives?

Before we go, we want to mention some of the other, less popular (for now), cow’s milk alternatives. 

  • Hemp milk - This is a great protein source and full of fatty acids. It’s also eco-friendly to grow because all parts of the plant can be used, meaning it generates less waste.
  • Pea protein milk - this alternative matches cow’s milk for nutrition, requires very little water and no irrigation, has a small carbon footprint and helps to pull nitrogen out of the air.
  • Coconut milk - as an environmentally friendly alternative, coconuts are very easy to grow, but grow in places that require a lot of transportation to the western world. It’s also not ideal for coffee as it may change the flavour too much, but it has become popular with people on the paleo diet.

One final consideration

If you buy quality coffee, the flavour alone should offer a rich drinking experience. Perhaps it’s time to try black coffee and really minimise the carbon footprint of your caffeine consumption. 

Do you have any questions about milk that you’d like answered?