What Drinking Milk Every Day Does to Your Body

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Drinking milk every day can support your overall health by providing essential nutrients that benefit your body.
Milk is packed with calcium, vitamin D, and protein, which strengthen bones, support muscles, and reduce osteoporosis risk.
Milk’s combination of protein, fat, and water helps keep you full, hydrated, and energized throughout the day.

With the rising popularity of plant-based milk, it's easy to forget about the benefits of dairy. But when it comes to nutrition, cow's milk still reigns supreme; it's a source of essential vitamins and minerals as well as quality protein. Cow's milk is also generally less processed than plant-based varieties, which might be desirable if you're trying to eat more whole foods.

So, if you can tolerate dairy and enjoy the taste, it's worth adding milk to your daily rotation. What will happen if you do? Here, registered dietitians share how drinking milk every day affects your body, plus how much to drink for the most benefits.

Roxana Ehsani, MS, RD, CSSD, LDN, sports dietitian and adjunct instructor at Virginia Tech University
Diane Lindsay-Adler, RDN, CDN, assistant professor of pediatrics at New York Medical College
Nicole Roach, RD, CDN, CDCES, Northwell's Lenox Hill Hospital

What Drinking Milk Every Day Does to Your Body

Milk was a desirable daily staple for decades. Its popularity started to dip in the late 20th century as dietary advice shifted. Concerns about saturated fat and cholesterol made whole milk seem less healthy. Now, scientific research points to the many positives of drinking milk daily.

Improves Bone Health

"Drinking a glass of dairy milk every day provides essential bone-supporting nutrients, including calcium, vitamin D, phosphorus, magnesium, potassium, and protein," says Roxana Ehsani, MS, RD, CSSD, LDN, sports dietitian and adjunct instructor at Virginia Tech. Specifically, one cup of dairy milk offers 310 milligrams of calcium (about 25 percent of your daily needs) and 8 grams of complete protein, according to Ehsani. The same serving also provides about 2.9 micrograms of vitamin D, a nutrient that's found in fortified milk.

"Calcium provides the structural foundation of bone, vitamin D enhances calcium absorption, and protein supports the collagen matrix," says Diane Lindsay-Adler, RDN, CDN, assistant professor of pediatrics at New York Medical College. These nutrients are important during periods of growth and help reduce the risk of osteoporosis and fractures later in life, says Lindsay-Adler.

Increases Protein Intake

"The protein in milk can significantly contribute to your daily protein intake," Ehsani says. "Milk provides all nine essential amino acids, making it a complete, high-quality source of protein," she notes. Thus, drinking milk daily may be helpful if you're trying to build muscle, recover from illness, or eat more protein as you age.

Repairs Muscle

As mentioned, milk is a complete protein. This means it contains all the essential amino acids needed for muscle repair and maintenance, says Lindsay-Adler. It's especially rich in branched-chain amino acids (leucine, isoleucine, and valine), which are absorbed directly from the small intestine into the bloodstream and taken up by skeletal muscle, Lindsay-Adler says.

Milk contains a combination of protein, carbohydrates, and fat; the latter depends on the type of milk. Together, these nutrients contribute to satiety, or the feeling of fullness. "Protein plays a central role by slowing digestion and stimulating hormones that signal fullness, while fat delays stomach emptying and enhances satisfaction after eating," says Lindsay-Adler.

Additionally, whole milk may keep you full longer due to its fat content, although it also provides more calories, she notes. The proteins in milk (whey and casein) also work together, as whey is digested quickly and casein provides a more sustained effect, helping reduce hunger between meals, says Lindsay-Adler.

Provides Hydration

Another benefit of drinking milk daily is better hydration. "According to the International Dairy Foods Association, milk contains approximately 87 percent water," says Nicole Roach, RD, CDN, CDCES, at Northwell's Lenox Hill Hospital. This can help you meet your daily fluid needs, which is important for energy, regulating body temperature, removing waste, and more.

Milk also provides major electrolytes, including sodium and potassium, which support hydration, says Ehsani. "We lose electrolytes every day through breathing, sweating, [and] urine and bowel movements. Electrolytes help maintain fluid balance within the body," Ehsani says.

Better Heart Health

"Milk provides nutrients, such as potassium and calcium, that support cardiovascular function," says Lindsay-Adler. "Potassium helps regulate blood pressure by balancing sodium levels, while calcium supports normal blood vessel contraction and relaxation," she says. But take note: Full-fat dairy milk contains saturated fat, which may contribute to elevated LDL ("bad") cholesterol levels in some people when consumed in excess, says Lindsay-Adler.

How Much Should You Drink?

For adults, three servings of dairy per day are recommended, according to the Dietary Guidelines for Americans. A typical serving size of milk is considered to be one cup (8 ounces), notes Roach. Your three daily servings can consist of three cups of milk—or a combination of milk and different forms of dairy, such as cheese, yogurt, and kefir.

The exception is if you're allergic to milk. In this case, you should avoid dairy, says Lindsay-Adler.

What Type of Milk Should You Drink?

The "best" type of milk depends on your age, health goals, and overall diet, says Lindsay-Adler. For example, it's recommended for children ages 12 to 24 months to drink whole milk, as it will support growth and development, she notes. "Older children and adults may choose low-fat or fat-free milk, while individuals with higher energy needs may benefit from whole milk," says Lindsay-Adler. If you have heart disease, choosing a lower-fat milk can help reduce the amount of saturated fat you're consuming, according to Roach.

Lactose-Free Milk

If you have lactose intolerance, you can still reap the benefits of milk by drinking lactose-free versions. "Lactose-free milk contains all of the same nutrients as regular dairy milk, just minus the lactose," says Ehsani. This includes vitamins, minerals, and protein. "The only key difference is lactose-free milk is treated with lactase to break down lactose, making it easier for someone with intolerance to digest," Ehsani says.

Ways to Use Milk

The simplest way to drink milk is to enjoy it by the glass. But if you're craving variety, consider these ideas:

Use milk to add protein to your favorite smoothie.
When making soup, add milk during the last few minutes of cooking to create a creamy texture.
Add milk to coffee or tea.
Make hot chocolate by combining warm milk and cocoa powder, suggests Lindsay-Adler.
Sip on a golden latte made with milk.
Prepare overnight oats or cereal with milk.