Milk has a bad reputation in the wellness world, with some claiming it causes everything from acne to inflammation. But what actually happens to your body when you drink milk every day? Here's what the research has to say.
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Milk (and dairy in general) gets the blame for a lot of unwanted health outcomes. We're sure you've heard that dairy causes acne, increases inflammation and can even be the reason you're not losing weight. Spoiler: For those who aren't lactose-intolerant or allergic to dairy, research doesn't back up those claims. In fact, there are actually some impressive benefits that come with drinking a nutritious glass of milk.

An 8-ounce serving of milk boasts 8 grams of protein, 50% of your daily needs of vitamin B12, 25% of your daily calcium needs and 15% of your daily needs of potassium and vitamin D, all in just 122 calories. Not to mention, it's way more affordable than many nondairy milk alternatives, like almond or oat milks. But what exactly happens to your body when you drink milk every day? We dug into the research to share just that.

(Note: For our purposes, a serving of milk is 8 ounces. In other words, this is the size of a small glass, not a large 16-ounce pint glass.)

Milk from a jug pouring into glass on a blue background
Credit: Getty Images / showcake

Your bone health might improve 

Not only is milk a great vegetarian protein source, but it's also packed with calcium and vitamin D—two nutrients that are vital for bone health. Calcium is a mineral needed to build and maintain strong bones, and vitamin D helps our body absorb calcium from the foods we eat. Since milk is a great source of both of these nutrients, it's one of the best things to keep in your diet for bone health throughout life.

You might lose weight 

There are lots of misconceptions about how drinking milk can affect weight, but research shows regular consumption probably won't hurt your cause if you're trying to lose weight or maintain a healthy weight. This is largely due to the satisfying combination of carbohydrates, protein and fat found in milk. Protein and fat can help make milk super filling, which can help with weight loss. Carbs give you energy and help your body function at its best. When you're more satisfied from the foods you eat, it's easier to honor your hunger and fullness levels and stick to a healthy, balanced eating pattern.

A meta-analysis of randomized controlled trials (the gold standard of research) published in the journal Nutrients found that including dairy in a calorie-restricted diet resulted in greater weight loss and fat loss, while reducing loss of lean muscle. This doesn't mean milk is a miracle weight-loss food, though. Another review of studies found that consuming milk or other dairy products didn't result in significant weight loss, but didn't lead to weight gain either. If your goal is to lose weight or maintain a healthy weight, drinking a glass of milk each day might help, if it's a food you enjoy.

You might lower your diabetes risk 

Being a milk drinker could help lower your risk of developing type 2 diabetes. One analysis of 22 studies (involving almost 600,000 people) found that total dairy consumption was inversely related with diabetes risk. This means that the more regularly people consumed dairy, the less likely they were to develop the disease. Other studies have found that replacing sugar-sweetened beverage consumption with milk helped lower type 2 diabetes risk as well. 

You might help your heart health—and probably won't hurt it

There is a lot of conflicting evidence when it comes to how milk influences heart health. Remember the days where low-fat diets were all the rage and skim milk was the only milk people were drinking? That could be partially responsible for the confusion. Luckily, now we know that fat is an important component of a healthy diet. However, milk's relationship to heart health is a bit more complicated.  

Some studies find that dairy products lower the risk of stroke, cardiovascular disease and hypertension, which could be due to their potassium content, while other studies find that they're associated with a higher risk of stroke, largely due to the saturated fat content. And numerous studies find that milk consumption and heart disease are not related at all. So what does it all mean? Overall, most of the recent research finds that milk has either a slightly beneficial or a neutral effect on heart health. As with any other food, if you like it, enjoy it in moderation.

You might lower your risk of cognitive decline 

The impressive nutrition profile of milk could be a reason why it can help you stay more mentally sharp as you age. A review of studies found that milk intake was connected with a decreased risk of Alzheimer's disease. Another study in the journal Nutrients found that skimmed dairy, fermented dairy and buttermilk were associated with better executive functioning. So adding some milk to your morning oats or as a side to a snack may help boost your brain health. 

Researchers hypothesize that one reason milk might support healthy aging is the nutrition that it provides. Milk is a good source of calcium, protein and vitamin B12, all of which are critical nutrients for older adults.

You might decrease your risk for certain kinds of cancer—and potentially increase your risk for others 

When it comes to how milk consumption affects cancer risk, the answer is complicated. Research has found that it might reduce the risk of certain cancers, while increasing the risk for others. One review in Nutrition & Metabolism found that high milk intake was consistently associated with lower risk of colon and rectal cancers. While the researchers state that the mechanisms for this reduced risk of cancer are unclear, they hypothesize that the calcium in dairy products could have chemopreventive properties. But another study included in the review found high milk intake was associated with higher prostate cancer risk compared to lower milk consumption, due to its high calcium content (though these results were not seen for calcium supplements or nondairy sources of calcium). There was insufficient evidence to draw conclusions about breast cancer, bladder cancer, ovarian cancer and other types of cancers. 

To be clear, this doesn't mean that your daily glass of milk is going to give you cancer. But it does show that more research is needed to clarify the relationship of milk and certain types of cancers. 

The bottom line 

If you aren't lactose-intolerant or allergic to dairy, it's totally OK to enjoy a regular glass of milk each day. From improving bone health to helping mitigate cognitive decline, drinking milk and incorporating other dairy items into your diet can come with some health benefits. As with any food, remember that moderation is key (an 8-ounce serving of milk probably wouldn't completely fill many of the glasses in your cupboard). Since there are dairy farmers all across the U.S., try choosing milk that is produced locally. Making a connection with a local farmer can help you get a better-quality product that takes less of a toll on the environment, too.