Plant milks: what's best for your health and the environment?

The supermarket shelves are groaning under the weight of plant-based 'milk'. Old reliables such as almond, soya and oat are pitted against intriguing newcomers such as hemp and pea.

According to research from The Grocer, 62% of people have bought a plant-based milk alternative before. And, of those, 70% are buying plant-based milks at least once or twice a month.

Some consumers choose non-dairy options for sustainability reasons, as well as health. So what’s really best for the environment, as well best for you?

Cow's milk

Cow's milk is a really good source of calcium and protein, including all nine essential amino acids.

Children under two should always be given whole milk, and skimmed milk shouldn’t be given to under fives. After this, the cow's milk you choose is up to you. 

Whole milk has more calories and fat. Choosing semi-skimmed or skimmed milk reduces the fat content without reducing the calcium, protein and most of the vitamins and minerals. But there are reasons that people may not be able to drink dairy milk.

According to Allergy UK, around 7% of babies under one have a cows-milk allergy, although most children grow out of it. 

Lactose intolerance affects around one in 10 older children and adults in the UK and means the digestive system has trouble breaking down lactose. This can cause bloating, diarrhoea and tummy cramps. It's more common in other parts of the world, such as Africa, Asia and South America. It's not the same as an allergy.

Additionally, the production of dairy milk has a significant impact on our environment, and some people may avoid it for these reasons. Vegans also don't drink cow's milk.

A 2018 study (Poore and Nemecek) found that global production of dairy milk had a carbon footprint three times higher than that of any plant milk. It used nine times more land and a great deal more water (twice as much as almond milk but 22 times as much as soya milk). When you look at the European dairy industry, those figures are considerably lower, but still significant. 

Environmental impact of different milks (per litre)

Source: Poore and Nemecek (2018), Science. Additional calculations, J. Poore

Bear in mind that these are worldwide and European figures so don’t take account of different national farming systems, some of which may mean impacts vary depending on what country you're in.

For cow's milk we've included mean global figures and European figures, as the cow's milk you buy in the supermarket is very likely to have been produced in the UK. The main ingredient in a plant milk may well have come from further afield, so we've used the global figures. 

Poore and Nemecek did include European figures for soya milk, oat milk and rice milk too. With the exception of water use for rice milk (where the European figure was significantly higher than the global average), all other figures were the same or lower for European production, so plant milks using ingredients grown closer to home may be better environmentally.

Nutritional comparison of cow's milk and plant-based milk alternatives

Plant milks labelled as organic can't be fortified, so if you want to make sure your plant milk is a source of calcium and other vitamins and minerals, you'll need to go for the non-organic versions.

Unsweetened versions will be better for your teeth.

Table notes: For each type of milk we looked at, we've included an original and unsweetened version if both were widely available. 

All of the non-organic plant milks are also fortified with Vitamin D at 0.75mg per 100ml (1.1µg in Oatly's case). 

Alpro Soya Drink (both sweetened and unsweetened) and Oatly also contain Vitamin B2.

Hemp seed milk alternatives contains naturally occurring omega 3 and omega 6.

Almond milk

Brands: Almond Breeze, Alpro, Blue Diamond, Califia Farms, Ecomil, Glebe Farm, Innocent, Nutty Bruce, Plenish, Provamel, Rude Health

Environmental impact of almond milk

While almond production involves low carbon emissions and land use, it's a very water-hungry crop. It still only requires two thirds of the amount that cow’s milk does globally, although in Europe cow's milk actually comes out better than almond for water use.

Almond milk has also come under criticism for the detrimental affects on the bees used to pollinate the almond orchards.

The pesticides, harsh conditions and exposure to disease leads to large numbers of bees dying – US commercial beekeepers now expect to lose 30% of their colony to almond production each year. But European (mainly Spanish) orchards are generally less intensive and use indigenous bee populations.

Summary: Environmentally, it’s not always the best choice. Choosing organic may limit the damage to bees caused by pesticides (but will then not be fortified).

Is almond milk good for you?

Almond milk is low calorie and low fat. It also contains natural vitamin E, which helps maintain healthy skin and eyes.

Like all plant milks aside from coconut, it contains a lot less saturated fat than cow’s milk – more than ten times less.

But almond milk is very low in protein. The almond milk we looked at contained less than 0.5g per 100ml compared with 3.6g for dairy milk and 3.3g for soya.

Typically, the quantity of almonds found in almond milk is very low – the brand we looked at had only 2% almonds. The main ingredient is water.

Summary: While almond milk is a low-calorie and low-fat choice, it's not a good nutritional substitute for dairy milk because it's very low in protein. It's a good source of vitamin E, but you can get the same from a handful of almonds, which will also contain a good amount of protein.

Cashew milk

Brands: Plenish, Rude Health

Environmental impact of cashew milk

Cashew nut milk wasn't assessed in Poore and Nemecek's study, but a 2022 paper published in the journal Sustainability Science by Cap, Bots and Scherer found that cashews had the worst environmental score of 10 nuts and seeds when ranked across 11 environmental, nutritional and social indicators. However, the data varied depending on the agricultural system used.

A recent study on the water used by treenuts and groundnuts found that cashews used the highest volume of water (although pistachios and almonds used more blue water – irrigated water as opposed to rainfall).

The top countries for cashew production include Ivory Coast, India and Vietnam.

Cashew harvesters and shellers need to be protected from the acidity found naturally in the shells – in the past, investigations have found workers suffering with serious burns.

Summary: Overall, the sustainability of cashews will depend on the agricultural system and climate they're grown in, but there are more sustainable plant milks available.

Is cashew milk good for you?

It's fairly similar to almond milk. It's low in calories and fat, including saturated fat, but it's also very low in protein. 

Plenish's cashew nut drink contains 4% cashews. The main ingredient is water and the only other ingredient is sea salt. The only cashew nut milks we could find widely available were organic (Plenish and Rude Health), so they're not fortified with calcium. Alpro's version has been discontinued.

Summary: Like almond milk, cashew milk is not a good nutritional substitute for dairy milk because of its low protein content, although it is a low fat and low calorie choice.

Coconut milk

Brands: Alpro, Glebe Farm, Koko, Plenish, Rude Health, UFC Velvet

Environmental impact of coconut milk

Coconut milk can’t be directly compared here as Poore and Nemecek didn’t assess it in their study. However, coconut milk would likely do pretty well on some measures, as coconut trees require very little water and don’t take up much land.

Unfortunately, there are other environmental negatives, largely because coconuts only grow in tropical environments. The worldwide demand for coconuts has led to them being grown in deforested tropical areas, harming biodiversity and exploiting poor communities.

If you do choose coconut milk, looking for Fairtrade certification will help to protect poor coconut farmers against low and volatile prices.

One of the brands we looked at, Koko, has a ‘monkey statement’ on its website promising that no animals are used to harvest its coconuts.

Coconut milk you buy tinned will have much less water and consequently be much richer and thicker than the carton coconut milk designed for use as a milk substitute.

Summary: While coconuts aren’t land and water intensive, they can only be grown in tropical environments, which can lead to other environmental issues.

Is coconut milk good for you?

It’s the only milk alternative we looked at that has a similar amount of saturated fat to dairy milk (for the Unsweetened version) or more (for the Original version).

It also has very little protein – the Original only has 0.2g per 100ml.

After water and coconut milk (8.4%), the next ingredient is grape juice concentrate.

Summary: It’s low in protein, so not a good direct substitute for milk. It’s also higher in saturated fat than any other milk alternative.

Hazelnut milk

Brands: Alpro, Innocent, Plenish, Rude Health

Environmental impact of hazelnut milk

Again, hazelnut milk isn't part of Poore and Nemecek's research. However, the study published in the journal Sustainability Science ranking 10 nuts and seeds across environmental, nutritional and social indicators placed hazelnut in the middle ranking group. But hazelnuts are actually pretty good for environmental factors such as carbon emissions, water use and land use – their middling score is down to other social factors such as the potential for poor workers' rights and child labour.

The WWF (World Wide Fund for Nature) backs this up, stating that hazelnut trees provide 'myriad environmental benefits' and 'ideal crops' as they are hardy, don't require much water and need little intervention from pesticides. But they're vulnerable to climate change, as most of the world's hazelnut supply comes from one place: the Black Sea region in Turkey.

Summary: Likely to be a good environmental option. 

Is hazelnut milk good for you?

It's very similar to the other nut milks we've looked at: low calorie and fat but also low in protein. 

Alpro's Hazelnut milk contains 2.8% hazelnuts. Water and then sugar are the largest ingredients - Alpro doesn't make an unsweetened version, although Plenish and Rude Health's cashew nut milks are unsweetened (but unfortified). 

Summary: Like almond milk, hazelnut milk is not a good nutritional substitute for dairy milk because of its low protein content, although it is a low fat and low calorie choice.

Hemp seed milk

Brands: Ecomil, Jord (oat and hemp blend), Sojade

Environmental impact of hemp seed milk

It wasn’t assessed in Poore and Nemecek's study, but hemp is regarded as a sustainable crop. According to a report by the European Commission on sustainable industrial crops, hemp requires little intervention to grow, is weed resistant and has very little need for pesticides or chemical treatment, as well as needing little water.

You can also use every part of the hemp plant for a variety of different uses, including clothing, paper and furniture. The recent explosion in demand for CBD means hemp is a hugely growing market worldwide.

There are controls on hemp cultivation in the UK, but it can be grown under licence.

Summary: While we can’t compare it with other non-dairy alternatives as it’s not included in the available data, hemp is a low-impact crop with some interesting sustainability credentials.

Is hemp seed milk good for you?

As a cow's milk substitute it’s not great, as it’s very low in protein. But it’s low calorie and low carb and, while it’s got more fat than any of the other milks we looked at, it’s low in saturated fat.

Hemp seed milk contains naturally occurring omega 3 and omega 6, which are essential for health. Vegans and those following a plant-based diet must take care to get enough of these, particularly omega 3, so hemp seed milk could be a useful source.

Good Hemp Seed is the only one of the milk alternatives we looked at that 's not fortified with calcium, vitamin B12 or vitamin D. There used to be an older fortified formulation, but Good Hemp has made the decision to make its product more natural.

The only hemp seed milks we could find available were organic, so they're  not fortified with calcium (and other vitamins and minerals). 

Summary: Not a good direct substitute for milk and because it’s not fortified, it's not the best option unless you're getting enough calcium from other sources.

Oat milk

Brand: Alpro, Biona, Califia Farms, Glebe Farm, Innocent, Jord, Moma, Minor Figures, Oatly, Plenish, Rude Health

Environmental impact of oat milk

Oat milk is the most popular plant-based milk alternative in the UK and is known for being particularly good in coffee.

Of the milks studied in the Poore and Nemecek research, oat milk does very well. Per litre, it uses 0.9 kg CO2e, 0.8 square metres of land and 48 litres of water – all significantly less than both global and European dairy figures.

But the other big environmental advantage is that oats can be easily grown in temperate climates, so are not associated with deforestation or loss of biodiversity.

One of the biggest oat milk brands, Oatly, tells you how much CO2 was emitted in the production, packaging and transportation of its product to store on every carton.

The product we looked at has a climate footprint of 0.47kg CO2e, much less than in the Poore and Nemecek research, but the way this is measured is slightly different from the Poore and Nemecek study so not directly comparable.

Oatly states that the packaging for its long-life products has a higher carbon impact than its chilled-product packaging because the long-life packaging requires an aluminium seal to protect the contents from spoiling. This means the CO2 emissions for chilled vs long-life products work out to be about the same once you add in the refrigeration emissions.

Summary: A really good environmental option.

Is oat milk good for you?

Oat milk is much lower in protein than semi-skimmed milk and higher in carbohydrates. It has a similar amount of calories and fat, although we looked at Oatly’s Semi product; Oatly’s Barista Edition has almost 3g of fat per 100ml.

Oat milk naturally has a sweet taste so is not typically sweetened. 

Oats (and oat milk) contain beta glucans, a type of soluble dietary fibre recognised for its cholesterol-lowering properties.

A 2016 systematic review and meta analysis found oat beta gluten could have a lowering effect on ‘bad’ cholesterol and could be a tool in reducing cardiovascular disease.

Oatly says one 250ml glass contains a third of your daily requirement of beta glucan.

Like the pea milk we looked at, Oatly is also fortified with iodine.

Oats make up 10% of Oatly’s milk, which is mixed with water. The third largest ingredient is rapeseed oil.

People are often confused about whether oats and oat milk are gluten-free. Oats are naturally gluten-free, but the way they're processed to make oat milk means they often contain traces of gluten, so oat milk can't be regarded as truly gluten-free. 

There are, however, some gluten-free brands such as Plenish and Rude Health. Both of these are organic and therefore unfortified.

Summary: Could be a good option if you're trying to lower or maintain healthy cholesterol levels, but bear in mind the low protein content.

Pea milk

Brands: Mighty Pea Society, Qwrkee, Ripple, Sproud

Environmental impact of pea milk

As a relatively new entrant to the market, pea milk wasn’t included in Poore and Nemecek’s analysis. Pea protein made from yellow split peas is fairly common now as a meat substitute, and interest in the crop is growing.

While yellow split peas are commonly grown as far afield as China, the Mighty (the brand we looked at) sources its peas from within the EU.

It has had its products certified by Mondra, a label that certifies ‘farm to fork’ eco-impacts of a product. It uses the same methods as the Poore and Nemecek study, so is directly comparable with those products.

This assessed that a litre of pea milk uses 0.34kg CO2e, 52 litres water and 0.5 sq m land, which is impressively low, particularly for carbon emissions (nearly 10 times less than global figures for cow’s milk and nearly 6.5 time less than the European figures).

Summary: A really good sustainable option, especially when the yellow split peas are grown closer to home.

Is pea milk good for you?

Pea milk is nutritionally similar to soya and a source of all essential amino acids. The Mighty original version contains almost as much protein per 100ml as dairy milk. Mighty pea milk also contains, after fortification, more calcium than any of the other milks, dairy included.

It also contains 21% of NRV (nutrient reference value) of iodine, which is the same as cow’s milk.

The Mighty says its aim is to provide a ‘high level of nutrition where other brands/variants provide little or fall short’.

As with soya milk, some people are allergic to pea protein/pea milk.

Summary: Similar nutritionally to soya milk and a protein-rich dairy milk substitute. The brand we looked at is fortified with more calcium than dairy milk.

Rice milk

Brands: Joya, Provamel , Rude Health, Riso Scotti, Tilda

Environmental impact of rice milk

Rice milk has a low impact in terms of land use but is the highest, after dairy milk, for carbon emissions. This is because rice farmers often flood rice fields, which breeds bacteria in the soil, leading to methane production. It also means water use can be very high.

Over-fertilisation is common in intensive rice agriculture, which can lead to soil degradation and water pollution.

Summary: Not the best environmental choice, because of water use and methane emissions.

Is rice milk good for you?

The brand we looked at, Joya, had the most calories per 100ml of any of the milks, including semi-skimmed dairy. However, it's low in fat and very low in saturated fat. It has the highest carbohydrate content and therefore sugar content (even though there’s no added sugar), and negligible protein.

Children under five shouldn’t be given rice milk, as it contains arsenic at levels that are safe for adults but not small children.

People are unlikely to be allergic to rice milk.

Summary: Not a good dairy milk substitute nutritionally – there is almost no protein. It has higher levels of natural sugar than other alternatives.

Soya milk

Brands: Alpro, Bonsoy, Glebe Farm, Plenish, Provamel, Rude Health, Sojade, Valsoia

Environmental impact of soya milk

On the three main factors considered in the Poore and Nemecek study, soya milk has the lowest overall impact. Most notably, it uses a fraction of the water of the global cow’s milk industry – more than 24 times less and more than 8 times less than European cow's milk.

But soya milk and other soya products have come under a great deal of fire in recent years, as it’s a crop heavily linked to deforestation and destruction of vital habitats, including the Amazon rainforest.

The reality is that the majority of all soya (more than 80%) is grown to feed to livestock. In the UK, dairy herds and beef cattle generally have a higher proportion of grass feed than in some other countries, but large quantities of soya are still used to feed poultry and pigs.

The soya milk brands mentioned above source their soya beans entirely from the USA, Canada or Europe, so are not linked to any deforestation in Brazil. If you find a different brand, perhaps abroad, it’s worth doing your research into the origins of the soya beans.

Summary: A good option as long as the soya beans have not come from areas with deforestation concerns.

Is soya milk good for you?

Nutritionally, soya milk has historically been the closest to dairy milk, as soya beans are a complete protein and contain all the essential amino acids. Pea milk is now a similar alternative.

Alpro Soya Drink is fortified to provide similar levels of calcium and vitamin B12 to dairy. Like all the milk alternatives we looked at (aside from hemp seed), it's also fortified with vitamin D (something that isn’t found in large quantities in dairy).

It's lower in calories than semi-skimmed milk but contains only very slightly less protein.

It’s low in saturated fat.

Soya is listed in Allergy UK’s top 14 allergens. Some children who are allergic to cow’s milk may also be allergic to soya.

Summary: A good alternative if you're looking for something similar nutritionally to cow’s milk.