Cow’s milk, a drink people often equate with good health, is one of the most popular US and European drinks.
Milk is a natural source of mammalian foods. Animals, including humans, produce milk until they are ready for solid food to feed their young.
Milk therefore contains valuable nutrients which help support a growing body including calcium and protein.
Milk study is inconsistent however, with various studies suggesting that milk is either good or bad for the body.
Popularity is growing because of increasing health concerns, lactose intolerance, and animal welfare, plant-based milk, and dairy alternatives.
This article discusses the potential health benefits of cow’s milk, as well as explore alternatives.
Health benefits of milk
Official sources, such as the 2015–2020 American Dietary Guidelines, suggest that adults consume about three cups of low-fat or fat-free dairy as part of a healthy diet each day.
This quantity can include milk, yogurt, cheese and beverages fortified with soy.
The following sections discuss possible benefits to human health from milk.
Milk and bone health
Calcium is an essential nutrient for healthy bones and teeth, nerve signals and muscle movement. Health officials are suggesting that you get enough calcium to help prevent bone fractures and osteoporosis.
Milk provides a rich calcium supply. Manufacturers use vitamin D to fortify cow’s milk, another nutrient that supports bone health.
Calcium is essential but not all studies agree that milk is good for preventing osteoporosis or fractures, as discussed in a 2019 study. Researchers have yet to do further work because of this disparity.
Milk and heart health
Milk is a potassium source which can help the blood vessels dilate and lower blood pressure.
Having more potassium while also raising the intake of sodium (salt) will improve blood pressure, decreasing the risk of heart disease and stroke.
Many in the U.S. don’t get their recommended daily potassium requirement of 3.400 milligrams (mg) in males and 2.600 mg in females.
In addition to the milk, other potassium-rich foods include:
- dried apricots
- oranges
- potatoes
- tomatoes
- lima beans
- spinach
- bananas
- prunes
- yogurt
Cow’s milk also contains a high quantity of saturated fat and cholesterol that can raise the risk of heart disease and people should eat milk in moderation.
Milk and cancer
Milk contains calcium and vitamin D, two nutrients which can help to prevent cancer.
Calcium can protect the gut lining to reduce the risk of cancer in the colon or rectum. Evidence has, however, related too much calcium to prostate cancer.
Vitamin D can play a part in regulating cell growth. It can help protect against colon cancer, and probably even cancer of the prostate and breast. Research has, however, also linked high levels of vitamin D to increased risk of pancreatic cancer.
There are many factors that affect the risk of cancer. Likewise, cancer can take a long time to develop so its causes and risk factors are difficult to study.
Scientists still need more long-term research to establish the facts with any certainty.
Milk and depression
Adequate levels of vitamin D promote serotonin development, which is correlated with mood, appetite and sleep by the hormone people.
Research has associated the vitamin D deficiency with clinical depression, including a study in 2020.
Manufacturers often use vitamin D to fortify cow’s milk, and plant milk.
Milk and muscle buildingon
Cow’s milk helps baby cows grow rapidly, so it makes sense that cow’s milk will help to grow muscles. Cow’s milk is a rich source of protein of high quality, containing all the essential amino acids.
Whole milk is also a rich energy source in the form of saturated fat which can prevent the use of muscle mass for energy.
Low fat milk can offer the benefits of milk while less fat is supplied.
Milk and osteoarthritis
There is currently no cure for knee osteoarthritis but researchers say they have linked daily drinking milk to reduced disease progression.
Their work appeared in the journal Arthritis Treatment & Work, of the American College of Rheumatology.
Nutrition: Milk and milk alternatives
The dairy group includes cow’s milk and soy milk according to the Dietary Guidelines for Americans 2015–2020. The group is composed of the following main nutrients:
- calcium
- phosphorus
- vitamin A
- vitamin D (in fortified products)
- riboflavin
- vitamin B-12
- protein
- potassium
- zinc
- choline
- magnesium
- selenium
The nutritional breakdown of milk depends on the fat content.
A 100-gram (g) serving of whole milk with 3.25% fat contains:
- 61 calories
- 4.8 g of carbohydrate
- 3.25 g of fat
- 3.15 g of protein
A 100-g serving of low fat milk contains:
- 43 calories
- 4.97 g of carbohydrates
- 0.97 g of fat
- 3.48 g of protein
A 100-g serving of soy milk contains:
- 33 calories
- 1.67 g of carbohydrates
- 1.67 g of fat
- 2.92 g of protein
Some important nutrients that all milk provides include:
Calcium
Dairy products are amongst the best dietary sources of calcium, including milk. Calcium is important for healthy bones and dents, blood clotting and blood pressure.
Combine calcium-rich foods with magnesium and vitamin D sources as vitamin D facilitates the absorption of calcium in the small intestine, and magnesium helps the body absorb calcium into the bones.
Choline
Choline is an essential resource for sleeping, moving bodies, learning and memory. It also helps with fat absorption, nerve impulses and inflammation.
Potassium
Potassium is vital to heart health, which includes reducing stroke risk, heart disease and high blood pressure.
A 100-g cow’s milk serving contains around 162 mg of potassium, slightly more than many soy milk drinks do.
However, in the case of lactose intolerance, a symptom such as diarrhea can cause depletion of potassium.
Fortified vitamins and minerals
Manufacturers fortify most milk with additional vitamins and minerals that are not naturally present, including cow’s, soy, almond and others. These added nutrients include vitamin A, vitamin B-12, riboflavin, and pyridoxine.
Light exposure kills some vitamins, particularly A and riboflavin, so there is lower nutrient levels in the milk that people store in transparent containers.
Concerns and precautions
The following sections look at the possible adverse health effects of drinking milk.
Saturated fats
Dairy has a high content of saturated fats. The American Heart Association (AHA) points out that eating too many saturated fats will increase cholesterol levels, thereby raising the risk of heart disease and stroke.
The AHA recommends that people from saturated fats earn no more than 5–6 percent of their total calories.
Lactose intolerance
Lactose intolerance is a disorder in which the body does not manufacture lactase, an enzyme that it needs to break down a sugar that exists in milk called lactose.
An estimated 65 percent of people have decreased ability after infancy to digest lactose. It is most common among people of East Asian descent and affects 70–100% of these populations
Milk allergy
An aversion to milk, or hypersensitivity, varies from lactose intolerance. The body responds in an allergy to the proteins, not to the sugars, in milk.
Aversion to milk from a cow can cause symptoms including wheezing and asthma, diarrhea, vomiting, and gastrointestinal distress. Severe allergies can lead to anaphylaxis, which is a life threatening reaction.
Too much potassium or phosphorous
It can be dangerous to get too much of the certain nutrients. Diet-only overconsumption is uncommon, but it can be made more likely by certain drugs or medical conditions.
If a person has kidney problems it can be harmful to get too much potassium or phosphorous. Too much of the potassium is considered hyperkalemia.
Too much calcium
Too much calcium or hypercalcemia may cause constipation, stones in the kidney or failure in the kidneys. It’s unusual for this to happen from diet alone, but a person taking calcium supplements may pose a risk.
Hormones and antibiotics
Cow’s milk can contain hormone and antibiotic residues, and dioxins and polychlorinated biphenyls (PCBs).
These residual substances can adversely affect human health, including adverse nervous system, reproductive system, and immune system effects. We will probably increase the risk of certain cancer types.
Although calcium and vitamin D from cow’s milk can be beneficial to bone health, there is also some evidence that animal proteins in the diet have an acidifying effect, for example from cow’s milk.
This could affect bone health, according to Harvard researchers, by forcing the body to take calcium out of the bones to maintain optimal levels of pH in the blood. However not everyone agrees with this.
As such, the net benefit of calcium can be lower than expected in cow’s milk.
For infants
The Centers for Disease Control and Safety (CDC) suggest infants should not be consuming cow’s milk before age 12. This is because cow’s milk can carry too many proteins and minerals for the kidneys of an infant and can put them at risk of intestinal bleeding.
Milk alternatives
Anyone who has an allergy or intolerance to cow’s milk, or who, for ethical or environmental reasons, is considering avoiding cow’s milk, can try alternative milk.
A number of substitute milks are available, such as almond, soy, coconut, hemp, and oat.
Soy beverages fortified with calcium, vitamin A and vitamin D form part of the dairy food group, as they have similar nutritional composition to milk, according to the American Dietary Guidelines.
Other milk alternatives made from plants may contain calcium but are not part of the dairy group as their nutritional profile is not similar to soy milk or cow’s milk.
Summary
Cow’s milk is a good source of calcium, phosphorus, and other important nutrients which can bring health benefits.
But milk is not needed for optimal health, according to one Harvard researcher. However, many others recommend it, and many people find the milk of cow an simple way to obtain essential nutrients, including calcium, vitamin D, and protein.
