A trip to the supermarket presents shoppers with an overwhelming number of milk choices. And far from just being the domain of the modern hipster, plant-based milk alternatives are going mainstream.
These alternatives may be suitable for people who are intolerant to dairy milk, or have ethical or other personal preferences. They tend to be lower in saturated fats and energy than dairy milk, but also lower in protein (except soy) and calcium (unless fortified). Some are also high in added sugars.
As to which milk is best, there’s no simple answer. Dairy milk tends to come out on top for nutrient quality, though soy is a good substitute from a nutrition perspective. And it should be noted these alternatives aren’t technically milks, as they’re not derived from mammals.
Nevertheless, the nutritional quality of the different alternatives varies considerably, so it’s important to take note of these differences when making a selection.
Milk provides us with important nutrients including calcium, protein, vitamin B12, vitamin A, vitamin D, riboflavin (B2), zinc, phosphorus and iodine. The quantity and quality of cow’s milk proteins is high, with both whey and casein containing all nine essential amino acids. Milk plays an important role in bone health and is a particularly rich source of dietary calcium.
Research investigating the ability of the body to absorb and utilise calcium determined the best-absorbed calcium source is dairy milk and its derivatives.
Although dairy foods do contain some saturated fats, the fat in dairy doesn’t seem to be overly problematic for heart health. A large study featuring people from 21 countries, published in 2018, found dairy consumption was associated with lower risk of heart disease and death.
Although dairy milk has a high nutritional value, there’s no reason why people need to drink it if they choose not to. All of the nutrients in milk can be obtained elsewhere in the diet.
If you’re seeking a dairy-free alternative, then soy is a good choice (though some people may be intolerant to soy). It’s made from ground soy beans or soy protein powder, water and vegetable oils and is usually fortified with vitamins and minerals including calcium.
A 2017 study found soy fared considerably better than other milk alternatives including almond, rice and coconut varieties in terms of nutritional profile.
Available in full-fat and low-fat versions, soy is a good source of plant protein, carbohydrates, B vitamins and most are fortified with calcium making it nutritionally comparable to dairy milk. The ability of the body to absorb and utilise the added calcium in soy drink is approaching that of dairy milk. One study indicated calcium from fortified soy drink was absorbed at 75% the efficiency of calcium from dairy milk, though there appears to be limited data on this.
It typically contains more protein than other plant-based alternatives, and contains healthy unsaturated fats and fibre.