by Would you like regular milk with that? The question that accompanies every modern coffee shop order. Depending on how fashionable the establishment is, whispering “cow’s milk” could be an illegal act.
According to Starbucks, the UK is the “alt-milk” capital of Europe, with non-dairy alternatives accounting for 16 per cent of its drink sales in 2023.
Reasons of taste, concern for the environment and animal welfare may be part of your decision making process. But what about health?
In the northern hemisphere, where we have a long history of cattle farming, it is a major part of our diet.
“It’s not that we have to drink it or can’t live without it, but if you were to take it out of the average British diet you would have to think carefully about where else you would get the nutrients that milk provides . ,” says nutrition scientist Bridget Benelam of the British Nutrition Foundation.
These are nutrients that can be hard to find elsewhere and are important for our development and health – “something you have to take into account if you’re switching from dairy,” says Benelam.
So what are the important vitamins in your glass of cow’s milk and how does it compare to the alternatives?
Protein
Milk is a rich source of two types of protein: casein and whey. Casein makes up 80 percent of the proteins in milk and is noted for its ability to increase the absorption of minerals, such as calcium and phosphorus. Whey, which consists of 20 percent, is known for being rich in amino acids such as leucine, isoleucine, and valine.
“Compared to the alternatives, it’s generally a better protein source; more protein is about 3.4 grams per 100 ml,” explains Duane Mellor, a nutritionist at Aston University in Birmingham. “Soya milk is the only one that comes close. Oats are about 2g. Rice milk and almond milk are much lower.”
Calcium
This nutrient is needed to build and maintain healthy bones, but it also helps keep muscles, nerves and teeth healthy. According to the British Nutrition Foundation, adults need around 700mg of calcium per day.
“Dairy products are one of the main sources of calcium in the UK diet. A 200ml glass of skimmed milk, for example, will provide 34 per cent of an adult’s daily requirement for calcium,” says Benelam.
B12
One of eight B vitamins, B12 is also known as cobalamin and is essential for healthy metabolism. B12 deficiency can also cause megaloblastic anemia, a blood condition that makes people feel tired and weak.
“This is also a vitamin that becomes harder to absorb as we age and we can only get it from animal foods,” says Mellor.
One glass (250 ml) of milk provides about 50 percent of the recommended daily allowance.
Iodine
The body needs iodine to make thyroid hormones, which control the body’s metabolism and many other important functions.
“In southeast Asia they get their iodine in their diet, mainly from seaweed,” says Mellor. But traditionally, in the northern hemisphere, we found it in dairy products. “Other countries add iodine to their salt, but we don’t in the UK,” says Mellor.
A 200ml glass of milk provides 34 per cent of the World Health Organization recommended iodine intake for adults per day.
Riboflavin
Remember the days of untreated milk in glass bottles with a yellow, creamy top? “That color is riboflavin,” says Mellor. Also known as B2, it has several roles. Its main link is with metabolism and energy release.
“If you don’t have enough you can get ariboflavinosis, a condition that causes cracking in the corners of the mouth and can change the texture of the tongue. Riboflavin is the most abundant and bioavailable B-vitamin in milk.
However, it is very sensitive to degradation. Riboflavin content may vary depending on processing or type of milk; One study found that commercial milk in the summer had about 20 percent more riboflavin than milk in the winter, due to a change in diet from corn silage to pasture.
How does plant-based milk measure up
Although calcium, B12, iodine, riboflavin and vitamin D are often added to plant-based milks, fortification varies widely between brands. And if it’s organic, they’re not allowed by law to fortify it. “That’s a strange thing,” says Mellor.
He recommends always scrutinizing the labels to see what levels of vitamins have been added.
“I want to look for ones that are fortified with calcium, riboflavin, iodine and ideally vitamin D. To get as close as you can to cow’s milk in terms of replacing those vitamins, look for at least 15-20 percent per 100ml volume in cow’s milk).
In general, dairy milk is not a good source of vitamin D, which is added to some plant milks.
A 2023 University of Minnesota study found that, compared to cow’s milk, only 12 percent of alternative milk products contained comparable or greater amounts of all three nutrients studied: calcium, vitamin D, and protein.
Watch out for added sugar too. Lactose is the sugar that occurs naturally in milk – it is the main carbohydrate in milk and provides the slightly sweet taste in plain, unsweetened milk.
“In cow’s milk the sugar is just lactose, which is digested slowly, but plant milk alternatives can be sweetened with fruit juice or added sugar,” says Mellor. “Added sugars tend to sell out quickly and are therefore considered less healthy.”
A common problem with vegan substitutes is that they are often functionally similar, but not nutritionally identical.
“Jackfruit is an example. In terms of texture it is a good substitute for meat, but in terms of nutrition it is not great at all. Same with vegan cheese, you’re getting the functionality but not the protein or the interesting fatty acids.”
In terms of milk this means that you may be able to achieve the same creaminess from oat or potato milk, but without the same nutritional content, unless your milk is heavily fortified.
What if I am lactose intolerant?
Northern Europeans have adapted, by raising cattle and drinking milk for several thousand years, to retain the lactase enzyme that breaks down lactose. However, in the UK, it is estimated that around one in 10 older children and adults have true lactose intolerance.
However, a 2021 study from the University of Bristol found that thousands of babies are being misdiagnosed with a cow’s milk allergy. “There are many things that could cause us uncomfortable symptoms,” Benelam says of misdiagnosis. “Maybe people are avoiding dairy when they don’t need to.”
“The symptoms of lactose intolerance are a bit difficult to pinpoint, as the gastrointestinal symptoms will vary from person to person and will be of different magnitudes. It can be a subtle condition,” says Benelam.
Dairy products
But dairy, including full-fat milk, is quite high in fat – is that a concern? “We usually advise people to cut back on saturated fat and replace it with unsaturated fat, but there is evidence to suggest that saturated fats in dairy such as milk and cheese may not raise cholesterol the way you’d expect .”
The fat content of that milk doesn’t concern Mellor: “Most people consume about a third of a pint of milk a day, in their tea or on their cereal. That’s not a significant amount of fat. It’s the other foods in their diet that are higher in saturated fats that are worse.”
However, as in all things, moderation is key. Drinking three or more glasses of milk is linked to an increased risk of bone fractures in women (the reason is not entirely clear, but d-galactose, a breakdown product of lactose, is linked to oxidative stress and inflammation), and excess. calcium from milk and other foods may increase the risk of prostate cancer, along with concerns about saturated fat.
“The overall health benefits of drinking milk are probably on the neutral side,” says Mellor. “You definitely get more benefits with fermented milk products, yogurt and some cheeses.”
Which cow’s milk is best?
Even the nutritional content of your cow’s milk can vary greatly. “Data shows that the time of year can affect the nutritional value of your milk,” says Mellor. “There tends to be more fat when the cows are better fed; you get richer milk when there is more grass in early summer.”
It also varies from cattle to cattle. “We know that Jersey milk is higher in fat and creamier than Holstein milk. Although the health benefits are not proven.”
Pasteurization is used in milk to extend shelf life and reduce the risk of foodborne illness. “Nutritionally there is no difference between pasteurized and unpasteurized,” says Benelam.
However, when choosing between full-fat, semi-skimmed and skimmed milk, there are subtle differences. “You get a little less vitamin A with skimmed milk because it’s fat soluble so it’s going to be in the fatty component of the milk.”
The other key vitamins are in the aqueous component of the milk: “So you don’t miss out on nutrients by choosing low-fat milk,” says Benelam.
Whole cow’s milk has more calories and saturated fat compared to semi-skimmed and plant-based options.
Switching from full-fat milk to semi-skimmed milk in tea (up to five cups per day) is likely to save the average person less than 50 kcal per day on average. This means that even when calories and energy are taken into account, the effect of reducing fat is negligible.
Quantity is key. “Certainly if you’re drinking sweet drinks like lattes and hot chocolates, there’s going to be a difference in terms of calories and fats. Choosing reduced-fat milk is a good idea for most people,” says Benelam. Conversely, skimmed milk can spike your blood sugar levels due to faster absorption. “Like so many things related to diet, it’s about balance.”
