Is soy milk good for you? Top 10 health benefits of soya milk

We take a deep dive into the world of soy milk to discover its many benefits and uncover the truth about its impact on our health and whether it’s really good for you…

Whether you’re a seasoned soy milk convert or thinking of making the switch, no doubt you’re aware of some of the benefits – and debates – surrounding this plant-based milk.

From health to environmental consequences, soy has been at the root of ethical conversations for decades, raising questions about whether it’s the best choice of plant milk for consumers.

Whilst the jury might be out on some aspects of soy milk, there are plenty of evident health benefits that back its case as a solid nutritional choice for dairy-free milk drinkers.

One of the biggest concerns around soy milk is centred on how it’s produced and the impact it has on deforestation in the Amazon region. But before we get into that, let’s take a look at some of the health benefits soy offers.

Jump to section

• Health benefits of soy milk
• What is soy milk made from?
• Soy milk calories and nutrients
• Impact of soy milk on health 
• Impact of soy milk on the environment
• How it compares to other types of milk
• Soy milk vs cow’s milk
• Things to be aware of
• Soy milk brands
• The rise of soy milk

Health benefits of soy milk

1. Nutrient-rich 

Soybeans (and therefore soy milk) is loaded with bioactive components which can help boost immunity¹. These include isoflavones – an antioxidant with potent anti-inflammatory properties that minimises oxidative stress and supports immune health.

2. Powerful source of vitamin A and zinc

This immune-boosting vitamin and mineral bolster the immune response, helping the body ward off acute and chronic illness², whilst supporting growth and development.

3. Protein and B Vitamins

Boasting all nine essential amino acids, soy is classed as a ‘complete protein’, making it a great support for energy levels and the development of healthy tissue. If you go for a fortified option, you’ll also benefit from B Vitamins including B6, B12, folate and riboflavin, providing additional benefits for energy, growth and metabolism³.

4. Benefits for sleep and the brain 

Other notable nutritional wins include magnesium and iron, both of which can support sleep, nervous system health and the production of healthy red blood cells. Soy milk also contains daidzein – an isoflavone which has been linked to brain health⁴.

5. The closest option to cow’s milk

Not only is soy milk a great vegan alternative to cow’s milk, it’s also the closest nutritionally. If you select a fortified soy milk, you’ll be getting comparable amounts of nutrients, but with way less fat and around a third of the calories.

Soy milk also has similar levels of calcium, but it’s worth noting that phytate – a naturally occurring compound in soy milk – can inhibit how much of that calcium your body absorbs⁵.

6. A source of healthy fats

Soy milk has around 2-4 grams of ‘good’ Omega-3 polyunsaturated and monounsaturated fats per cup⁵. This, combined with beneficial isoflavones and saponins (naturally occurring plant compounds) may help support heart health and prevent the onset of Alzheimer’s and Dementia⁶.

7. Lowering cholesterol

Whether it’s fortified or not, soy milk is an excellent source of potassium which is connected to a myriad of health benefits, including lower blood pressure⁷. Soy milk has also been linked to lowering cholesterol⁶, though more research is being carried out in this area.

8. Great for bone health

The added vitamins in fortified soy milk are essential for growing and maintaining healthy bones. This is backed by a 2022 report by the Journal of Clinical Medicine that revealed a direct link between soy isoflavones and the prevention of bone loss in postmenopausal women⁷.

9. May help with perimenopausal/menopausal symptoms

Soy isoflavones (also known as phytoestrogens) react in the body like a weak form of oestrogen, helping to lessen symptoms associated with perimenopause/menopause like changes in mood and hot flushes⁸.

These isoflavones have been widely researched and debated in research circles, with some studies even indicating a link to lower levels of breast cancer in some women⁹.

10. Naturally low in calories

Yet high in protein, vitamins and minerals makes soy milk a good all-rounder for weight maintenance, as part of a varied and nutritious healthy diet.

What is soy milk made from?

Soya milk is produced from tofu and is achieved by soaking soybeans, then boiling and straining the mixture before grinding it into a milk. Typically, large-seeded soybeans are used for soymilk production, with around 200 grams of beans yielding about 1 litre of soymilk¹¹.

Soy milk is often fortified with nutrients like calcium and vitamin D, but it can also be sweetened (often with cane sugar) with the intent to make it more palatable. You’ll likely see flavoured options on the shelf too, the majority of which will contain extra additives, stabilisers or thickeners – often identified on the nutritional label as ‘gum’.

Given soy milk is predominantly used in drinks and dishes with other flavourful ingredients, it’s generally best to opt for an unsweetened, fortified blend that will give you the best nutritional bang for your buck.

A good unsweetened soy milk can be made from just 2 ingredients – water and soybeans. Whereas a sweetened, flavoured version can have around 12 or more components  – including oils, gums and flavourings.

Soy milk calories and nutrients

Moreover, soy milk stands out with its rich soluble fibre content, ranging from 0.8 to 1.5 grams per 100 millilitres, which serves multiple health benefits.

This soluble fibre helps lower cholesterol levels and assists in stabilising blood sugar. Such qualities make it an excellent choice for those looking to enhance their heart health and maintain more consistent energy levels.

Soy milk carries a mild natural sweetness, attributed to the inherent sugars found in soybeans, making it unnecessary for manufacturers to add extra sugar to the final product. Major soy milk brands typically contain just over three grams of sugar per 100 millilitres, which is considered a modest amount.

The recommended daily fibre intake is around 30 grams, and soy milk can contribute to your daily quota. Within soy milk, you’ll also find beta-glucans, a type of soluble fibre, known for its ability to reduce cholesterol levels and assist in blood sugar regulation – further solidifying soy milk as a nutritious choice.

Impact of soy milk on health 

Viewed as a health food by many, fearfully shunned by others – soy milk has to be one of the most hotly debated plant milks out there when it comes to its impact on health and the environment.

Claims that link it to breast cancer, thyroid problems and dementia have not been substantiated¹². And it’s fair to say that the boundaries between fact and fiction have been unhelpfully blurred through contradictory study outcomes and popular – often sensationalist – media coverage.

Because of this, there seems to be a hesitancy to promote soy, which goes so far to explain the stagnant consumer trends that surround it.

Part of the uncertainty is down to soya milks’ unique makeup of isoflavones and how they impact the body. But there are so many factors to consider and since each consumer is totally unique, it’s very difficult to construct any solid conclusions on the health effects of soy.

Impact of soy milk on the environment

One of the biggest debates around soy milk is the impact it has on driving deforestation in the Amazon rainforest. Indeed, the growth in demand for soy has undoubtedly been a catalyst for Brazilian land use change, but this is largely driven by the demand for beef, not the production of soy milk.

To put it into context – a staggering 95% of Brazilian soy is used for animal feed, with soybean oil following in second place as a main by-product of soy plantations¹³.

Most of the soy milk we drink in the UK is actually produced in Europe, often to strict regulations that limit the use of genetically modified soy for human consumption. And it has a much lighter footprint than dairy and oat milks (and in some cases, almond) requiring less square metres of land and fewer litres of water to produce it.

When it comes to environmental impact soy milk, here’s a comparison table¹⁴:

How it compares to other types of milk

We already know that nutritionally, soya milk is the closest plant based equivalent to cows milk, but how does it fare in comparison to other popular plant based milks like almond, oat and coconut?

Oat milk – Compared with plain, unsweetened oat milk, soy milk is slightly higher in calories, and fat, but it’s also higher in potassium and iron, whilst being much lower in carbs. One cup (240 ml) of soy milk also provides significantly more protein (around 7-9 grams) than oat which has around 2g per cup.

Almond milk – With just 37 calories per cup, unsweetened almond milk is a low calorie option that has less than half of the calories of soy milk. But it’s much lower in protein and potassium. Almond milk is also made by soaking almonds and straining the liquid, removing most parts of the nut (including the fibre-rich skin) that are beneficial for health.

Coconut milk – Like soy, coconut milk really shines in smoothies and espresso style coffees. Nutritionally, it has less calories and marginally less fat than soy. It’s also super rich in calcium, boasting around 459 mg per cup – much higher than the 246mg found in soy.  Where it falls short against soy is potassium, fibre and protein.

Soy milk vs cow’s milk

Soy and cows’ milk have similar amounts of calcium, vitamin B12 and protein, but soy wins the race when it comes to riboflavin and vitamin D.

You’ll find more vitamin A, zinc and folate in cows’ milk, but these nutrients are easily obtainable from plant foods like leafy greens, beans, seeds and legumes.

Soy is also naturally free of lactose, cholesterol and antibiotics – unlike its dairy counterpart.

Beyond its nutritional advantages, soy milk also offers notable environmental benefits over cow’s milk.

Firstly, the production of soy milk generally has a lower environmental footprint compared to cow’s milk. This is because soybeans require less land, water, and feed resources, making them a more sustainable option.

Secondly, soy production typically generates fewer greenhouse gas emissions and has a lower impact on deforestation when compared to the livestock industry associated with cow’s milk production.

Opting for soy milk can thus contribute to reduced land use and decreased pressure on natural ecosystems, making it a more environmentally responsible choice for those concerned about the planet’s well-being.

Things to be aware of

Isoflavones

Isoflavones bring a lot of benefits to our diets, but it’s thought they could present negative side effects too, such as reducing thyroid function and how the body produces thyroid hormones.

However, as long as you consume enough iodine in your diet (commonly found in leafy greens, beans, corn, potatoes and some fruits) the impact to thyroid function is considered to be fairly insignificant.

Added sugars

Keep an eye out for added sugars. Unsweetened soy milk contains no added sugars, but sweetened varieties can contain anything between 4-20g of added sugars per 250ml serving. These significantly change the nutritional content of soy milk so be sure to check the label before you buy.

It’s inevitable that you’ll work through a few varieties before you find a flavour that aligns with your diet and flavour preferences. Fortunately the market has plenty of options on offer.

Allergies

It goes without saying that anyone with an allergy to soy should opt for a different plant milk and avoid using soya milk in recipes.

Soy milk brands

Soy milk is one of the most widely available vegan options out there. If you can’t get your usual oat, almond or coconut at the local store, chances are you’ll find soy on the shelf.

Some of the most popular soy milk brands in the UK include:

1. Alpro: Alpro is one of the most prominent brands of plant-based products in the UK, offering a wide range of soy milk products, including original, unsweetened, and flavoured varieties.
2. Provamel: Provamel is another popular brand known for its organic and sustainably sourced soy milk products.
3. Rude Health: Rude Health is known for its natural and organic food products, including soy milk and other dairy-free milks.
4. Plenish: Plenish offers organic and sustainably sourced soy milk, among other plant-based products.

Additionally, soy milk is easy to find at UK supermarkets, will all offering their own options in both sweetened and unsweetened versions.

In the US, the leading soy milk brands include:

1. Silk: Silk is one of the most well-known and widely available brands of soy milk in the United States. They offer various flavours, including original, vanilla, chocolate, and organic options.
2. So Delicious: So Delicious offers a range of dairy-free and plant-based products, including soy milk in both unsweetened and flavoured varieties.
3. WestSoy: WestSoy is known for its organic and non-GMO soy milk products, including original, unsweetened, and fortified options.
4. 365 by Whole Foods Market: Whole Foods Market’s in-house brand, 365, includes soy milk among its range of dairy alternatives.
5. Trader Joe’s: Trader Joe’s, a popular grocery store chain, offers its own brand of soy milk and other plant-based milk options.
6. Eden Foods: Eden Foods is known for its organic and non-GMO soy milk, which comes in various flavours and fortified options.
7. Kikkoman Pearl: Kikkoman, known for its soy sauce, also produces soy milk in the United States.
8. Vitasoy: Vitasoy is another brand that offers soy milk products, including regular and organic options.
9. Organic Valley: Organic Valley produces a variety of organic dairy alternatives, including soy milk.
10. Califia Farms: Califia Farms offers a range of plant-based milk alternatives, including soy milk. They provide both original and flavoured options.
11. Blue Diamond Almonds (Almond Breeze): While they are known for almond milk, Blue Diamond Almonds also produces soy milk under the Almond Breeze brand.

The rise of soy milk

Soy milk was originally consumed in China with evidence showing its first uses around 25-220 AD.

Popularised in the 90’s, soy milk was one of the first plant-based milks to land in the UK market, presenting a fresh alternative to dairy that became a convenient go-to for vegan and lactose-intolerant consumers.

The plant milk market has grown exponentially since. As consumers we have more variety than ever. Yet soy seems to have retained its popularity, remaining fairly stagnant in a market that sees other plant milks (such as oat and almond) more susceptible to trend-driven peaks and troughs.

Soy milk now forms part of a £963 million plant-based market here in the UK, with a 26% surge in plant-based milk drinkers between 2020-2022 alone¹⁰. And this growth is expected to flourish further, with the global plant based milk industry predicted to be worth $123.1 billion by 2030.

It’s the plant milk taking the world by storm, but is oat milk good for you? Find out here…

Featured photo © Ninetechno via Adobe Stock

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