When it comes to knowing which is the best milk for the planet – animal or plant-based – environmentalists will say that there is no doubt: plant-based milk always wins.
Advances in major dairy producing countries such as China, Italy, New Zealand and the United States (US) have dramatically increased modern milk production per cow. In the US, a cow currently produces four times more milk than a cow in India. All of this is done while reducing the animal’s environmental impact. There is even a cow, in the State of Wisconsin, called Selz-Pralle Aftershock 3918, which holds the world record for milk production from an animal of the Holstein breed: about 36 thousand liters of milk in 365 days.
According to a widely cited 2018 meta-analysis on the subject, the world’s demands on natural resources in order to feed and water dairy cows remain enormous.
The dairy industry uses approximately 10 times more land and between two to 20 times more water than soy, oat, almond or rice milk production, according to a 2018 analysis of the subject by the nonprofit organization Global Change Data Lab and the University of Oxford, UK.
According to this study, dairy products also generate about three times more greenhouse gas emissions. The belching and feces of ruminant animals, such as cattle, sheep and goats, generate methane. The Environmental Program of the United Nations Organization states that this is a greenhouse gas, 80 times more powerful than carbon dioxide, in terms of global warming, over a period of 20 years.
Still, people drink milk for nutritional reasons, and in some parts of the world, this food is a source of protein and nutrients. This can make the answer to which milk is best for you, your children, as well as the planet, more complicated. Here’s what science says.
Has milk?
The ad featuring a smiling cow with a milky mustache sends a message that is often repeated at home: milk is good for you. It has calcium, protein and other nutrients that help people get tall and strong.
“Nutritionally, milk is incredible, as a young mammal can live and grow for many months on nothing but milk,” nutrition researcher Walter Willett told CNN. “However, that doesn’t necessarily mean it’s an ideal food for life.”
Willett, Professor of Epidemiology and Nutrition at the Harvard TH Chan School of Public Health and Professor of Medicine at Harvard University, as well as his colleague David Ludwig, an endocrinologist and pediatrician also at Harvard, addressed the issue of milk and human health in a report by 2020 for The New England Journal of Medicine.
Strong bones: the pair of researchers examined the belief that drinking milk makes you have healthy bones, while being less likely to have fractures. Willett said this is the main rationale for current US nutritional recommendations of 3 cups of skim milk or other dairy products daily for children ages 9 to 18 and adults, while children ages 2 to 8 should drink, daily, about two and a half glasses of milk.
Interestingly, the meta-analysis report of these studies, which examined consumption of up to 4 glasses of milk a day, found no definite benefit for fracture prevention, even in children, Willett said. A 2014 study he and his colleagues did found that there is a 9% greater risk of hip fracture for each additional daily glass of milk consumed by teenage boys, but not by girls. When Willett and Ludwig made a country-by-country comparison, they found higher rates of hip fractures in countries where the highest amounts of milk and calcium were consumed.
Height: milk helps children grow taller. Much taller, Willett said. What’s wrong with this? Tall people suffer more bone fractures, he said, because “mechanically, if a person has a long dick, it’s easier to break it than to break a shorter one.”
Studies have also shown a link between height and an increased risk of many types of cancer and lung problems. Tall people seem to have less heart disease but are at greater risk for atrial fibrillation, irregular heartbeats and varicose veins.
Lactose intolerance: the introduction of dairy products into the diet of a human baby can only be done after 12 months, as they contain an overabundance of proteins and minerals. According to the US Centers for Disease Control and Prevention, dairy products given before a baby’s first year can cause intestinal bleeding and damage the kidneys.
But unless your ancestors are from a part of the world where it was genetically advantageous to consume dairy products, your body will stop producing the lactase enzyme in childhood. Without it, your body struggles to break down the sugars in the milk.
Studies estimate that 68% of the world’s population may be intolerant to milk. This causes people to have abdominal bloating, cramping, and pain.
“Milk and dairy products were mostly consumed in northern European countries,” said Willett. “Most of the world’s population does not consume milk after childhood.”
Hormones and antibiotics: dairy cows are almost always pregnant, Willett noted. This naturally increases the levels of progesterone, estrogen and other hormones in the milk. Similarly, to increase milk production today, cows are bred to produce higher levels of insulin-like growth factor 1, or IGF-1.
In humans, excess IGF-1 has been linked to cancer, insulin resistance and may play a role in age-related decline. Cattle can also be given antibiotics to keep infections in check. However, consumer concern about the impact of hormones and antibiotic resistance has increased.
Weight loss: Low-fat or skim milk is obviously a healthier choice than the sugary or “diet” sodas, teas and other processed beverages available on the market. However, studies of dairy products have shown that only yogurt is associated with less weight gain, Willett said.
The available evidence also does not show an advantage in drinking low-fat milk over full-fat milk as a way to control weight, either in adults or children. A 2020 meta-analysis report found that whole milk may contribute to less childhood obesity.
The verdict? “We have to look at everything we do through an environmental lens,” said Willett. “Not only is the answer zero dairy for everyone, but three glasses of milk a day are not necessary for health. However, they are a disaster for the environment.”
Willett points to the target of 250 grams or 1 serving of dairy per day set by the EAT-Lancet Commission, which tries to create a universal diet that is healthy and sustainable.
“That daily serving is probably best in the form of an unsweetened yogurt or maybe a cheese. If you want, you can add some plant-based milk alternatives,” Willett said. “I think from a health and environmental point of view this is a reasonable starting point.”
Best vegetable milk
The plant-based milk market is booming.
“Almost all nuts, as well as legumes and grains are becoming options for plant-based milks. The newest alternative I’ve found is banana milk,” said Christopher Gardner, nutrition expert, professor and researcher of medicine at the Stanford Center for Research and Prevention in California. He is writing a chapter of a book about milk.
So far, Gardner has found milks based on legumes (soy, peas, peanuts, lupine and black-eyed peas), nuts (almonds, coconut, hazelnuts, pistachios, walnuts, macadamia and cashews), seeds (sesame, flax, hemp and sunflower ), grains (oats, rice, corn, spelt, quinoa, teff and amaranth) and a potato milk.
Impact on the environment: Science has not yet analyzed the environmental impact of each new entry into the alternative milk market, but it can compare rice milk to soy, almond and oat milk.
The winner? According to analysis by the organization Global Change Data Lab, it depends. Rice has the least impact on land use, almond has the least impact on greenhouse gas emissions, and soy has the least impact on freshwater use and eutrophication. This is the process of contaminating the water with nutrients, which cause excessive plant and algae growth. Oat milks are somewhere in between.
According to Gardner, in nutritional terms, each category of alternative milk has pros and cons compared to dairy. Likewise, he was not able to analyze all the brands on the market, which are “too numerous to be realistically evaluated”.
Calcium: dairy is the winner. However, plant milk manufacturers have solved this problem by adding calcium. Thus, they ensure that their milk has at least 300 milligrams of this mineral, which is the level of calcium present in dairy products.
“The exceptions I found were coconut and rice milk. Some brands boast levels of 130 milligrams of calcium per serving or less,” he said.
Protein: soy milk and pea milk, for example, have as much protein as dairy products – about 8 grams of protein in each glass that holds about 236 milliliters. Other legume-based milks are also good choices.
However, coconut milk and rice have negligible levels of protein. Almond milk has less than a gram of protein per serving and oat milks range between 1 and 3 grams per serving.
Fat, sodium and cholesterol: Compared to the dietary cholesterol in full-fat dairy, most plant-based milks are good choices – plant foods never have dietary cholesterol. Sodium levels are relatively equal between plant milks and dairy products: they have about 100 milligrams of sodium. He added that saturated fats are low, with the exception of coconut milk, as this tropical plant has high levels of fat.
“There’s no need to be afraid of the fat in most plant-based milks. Unsaturated fats are considered healthy in the modest amounts found in plant-based milks,” Gardner said.
Vitamins A, D and B12: the only reason dairy products are a good source of vitamins A and D is that they are fortified with these vitamins when manufactured. Therefore, vegetable milks did the same.
Vitamin B12 occurs naturally in dairy products in very small amounts, as cows obtain the vitamin through grass bacteria from pastures. Some plant-based milks are fortified with B12, but not all. To find out, he says to look on the label for the name cobalamin, which is the technical name for this vitamin.
sweeteners: Dairy products have their own sweetener: lactose. This is the sugar that many people find causes stomach irritation.
“For milk of animal origin, lactose is a natural sugar present in this drink. For that reason, it’s included as part of the total sugar content, but it’s not considered an added sugar,” explained Gardner.
Vegetable milks do not have this advantage. This is where nutrition hits a snag. In general, original versions of almond, soy and coconut milks have added cane sugar to match the level of sweetness found in dairy products. Vanilla and chocolate options have even more added sugars.
However, many alternative milk brands offer an unsweetened version. “No added sugar, total carbohydrates tend to be lower, total sugar tends to be lower, and added sugars tend to be zero,” he said.
“Try the sugar-free versions. Generally, these are just as tasty as the original version. However, they have fewer calories, less carbohydrates, less sugars and less added sugars.”
