Milk being poured in coffee
Soy milk is the most nutritionally balanced plant-based milk better than cow's milk Anete Lūsiņa/Unsplash

Soy milk is the most nutritionally balanced plant-based milk, according to a new study.

It comes as requests for a nut-milk cappuccino in the morning is no longer considered the exclusive preserve of those with lactose intolerance or vegans. Between 2009 and 2015, nut milk sales have more than doubled, and in 2017 Alpro - the market leader of plant-based products including soya and almond milks - saw its UK sales increase by 14% in a year.

Nut milk converts may have avoided cow's milk because it sits better with their digestion, or because they don't feel comfortable with consuming animal products. But as almond milk sales have climbed, soy milk have dropped, Munchies reported.

However, shunning soy milk might not be the most nutritionally sound decision, according to a review by McGill University, Canada. Researchers reached this conclusion after they compared the nutritional values of unsweetened almond, soy, rice and coconut milk varieties with cow's milk.

The research showed that soy milk had anti-carcinogenic properties, but that it had a presence of anti-nutrients, or substances that reduced nutrient intake and digestion. Researchers also noted it had a "beany" taste that might be off-putting.

Rice milk, meanwhile, tasted sweet and was found to be a suitable alternative for those who have an intolerance to lactose, as well as soybeans and nuts. But the study noted it was higher in carbohydrates, and also raised the risk of malnutrition, particularly in infants.

The investigation showed that coconut milk, which is widely consumed in Asia and South America, could reduce the levels of low-density lipoproteins, or bad cholesterol, linked to cardiovascular disease. It also became less nutritious if it was stored for longer than two months.

Almond milk was high in monounsaturated fatty acids, which have been linked to weight loss and management, and help to reduce bad cholesterol.

Researchers also highlighted that cow's milk was nutritionally complete and contained fats, carbohydrates and proteins. It also contained proteins which have beneficial effects for the immune system.

"For most people, cow's milk is an important source of protein and calcium," Aisling Piggott, British Dietetic Association spokesperson told IBTimes UK. "If you are using a cow's milk alternative, make sure you choose one fortified with calcium."

"Remember that vitamin D is responsible for the absorption of calcium in the body, and we should all be considering vitamin D supplementation especially during winter months," she said, adding: "Be aware that soya, nut and other milk alternatives are much lower in energy and protein than cow's milk so paying attention to the rest of your diet, and the energy and or protein content is important.

"Many milk alternatives are much lower in iodine than cow's milk, and whilst there are talks about fortification, those with very low levels or excluding cow's milk from their diet should think about supplementation."