Cow's milk has long been associated with good health, making it one of the most consumed beverages throughout the United States and Europe.
Milk has long been seen as a healthy drink, because it is high in a range of nutrients. The U.S. Department of Agriculture (USDA) guidelines for 2015 to 2020 suggest that Americans should consume "Fat-free or low-fat dairy, including milk, yogurt, cheese, and/or fortified soy beverages."
However, they also recommend consuming fewer than 10 percent of calories each day from saturated fats, citing butter and whole milk as examples of foods high in saturated fat.
Milk and bone health
Milk is good for the bones because it offers a rich source of calcium, a mineral essential for healthy bones and teeth. Cow's milk is fortified with vitamin D, which also benefits bone health. Calcium and vitamin D help prevent osteoporosis.
Other ways to improve bone health and reduce the risk of osteoporosis include regular physical activity and strength training, avoiding smoking and eating a healthy diet that is low in sodium and high in potassium. Most of the body's vitamin D is synthesized by the body on exposure to sunlight, so spending time outdoors is also important.
Milk and heart health
Cow's milk is a source of potassium, which can enhance vasodilation and reduce blood pressure.
Increasing potassium intake and decreasing sodium can reduce the risk of cardiovascular disease, according to a study led by Dr. Mark Houston, director of the Hypertension Institute at St. Thomas Hospital in Tennessee.3
The study showed that those who consumed 4069 mg of potassium per day had a 49 percent lower risk of death from ischemic heart disease compared with those who consumed around 1000 mg per day.3
According to the National Health and Nutrition Examination Survey, fewer than 2 percent of US adults meet the daily 4700 mg recommendation.3
Potassium-rich foods include cow's milk, oranges, tomatoes, lima beans, spinach, bananas, prunes, and yogurt. A dramatic increase in potassium intake can have risks however, including heart problems, so any changes in diet or use of supplements must be discussed first with a physician.
Cow's milk also contains a high amount of saturated fat and cholesterol, which have been linked to an increased risk of heart disease.
Milk and cancer
Vitamin D might play a role in cell growth regulation and cancer protection. Research shows that there is a higher risk of dying from colorectal cancer in geographic locations that receive the least amount of sunlight. Milk, too, contains vitamin D that can offer similar protection.
The National Cancer Institute (NCI) states that "Research results overall support a relationship between higher intakes of calcium and reduced risks of colorectal cancer." They note, however, that the results of studies have not always been consistent."2
The NCI also points to some studies that suggest an increased intake of calcium and lactose from dairy products may help to prevent ovarian cancer.2
Milk and depression
Adequate vitamin D levels support the production of serotonin, a hormone associated with mood, appetite, and sleep. Vitamin D deficiency has been associated with depression, chronic fatigue, and PMS. Cow's milk and other foods are often fortified with vitamin D.
Milk and muscle building
Cow's milk is designed to help baby cows grow fast, so it makes sense that humans who drink cow's milk can also bulk up quickly. Cow's milk is a rich source of high-quality protein, containing all of the essential amino acids. Whole milk is also a rich source of energy in the form of saturated fat, which can prevent muscle mass being used for energy.
Maintaining a healthy amount of muscle is important for supporting metabolism and contributing to weight loss and weight maintenance. Sufficient dietary protein is needed to preserve or increase lean muscle mass. Dairy protein can support muscle growth and repair.
According to Today's Dietitian, an analysis of over 20 clinical trials suggests that an increased milk intake can boost muscle mass and strength during resistance exercise in both younger and older adults.6
Cow's milk does not seem to significantly help with weight loss. One analysis of studies found that increased consumption of cow's milk in the short-term and without calorie restriction had no benefit for weight loss, with only modest benefits seen in long-term studies with energy restriction.11
Low-fat milk can provide the benefits of milk while supplying less fat.
Milk and osteoarthritis
Osteoarthritis of the knee currently has no cure, but researchers say drinking milk every day has been linked to reduced progression of the disease. Their research was published in the American College of Rheumatology Journal Arthritis Care & Research.
One cup of whole milk, with 3.25 percent fat contains:
8 grams of fat
13 grams of carbohydrates
8 grams of protein
One cup of nonfat or skim milk contains:
0 grams of fat
12 grams of carbohydrates
8 grams of protein
In comparison, one cup of plain soy milk contains:
3 to 4 grams of fat
6 to 7 grams of carbohydrates
5 to 7 grams of protein
One cup of plain almond milk contains:
50 to 60 calories
2.5 grams of fat
5 to 7 grams of carbohydrates
1 gram of protein
Some important nutrients that all milk provides include:
Calcium: Dairy products like milk are one of the richest dietary sources of calcium. Calcium has many functions in the body but its primary job is the development and maintenance of healthy bones and teeth.
Calcium is also important for blood clotting and wound healing, maintaining normal blood pressure, and muscle contractions including heartbeat. It is important to try to pair calcium-rich foods with sources of magnesium and vitamin D, as vitamin D supports calcium absorption in the small intestine and magnesium helps the body incorporate calcium into the bones.
A cup of skim milk contains around 306 milligrams of calcium, with around 32 percent of this calcium thought to be absorbed. Non-acidifying plant sources of calcium may be preferable for some people, with the absorption of calcium from kale, broccoli and other vegetables ranging from 40 to 64 percent.8,9
Choline: Milk is also a rich source of choline; an important nutrient found to support sleep, muscle movement, learning and memory. Choline helps to maintain the structure of cellular membranes, aids in the transmission of nerve impulses, assists in the absorption of fat and can lessen chronic inflammation.
(Image: Representation only)