Drinking Protein Shakes With Milk Has Some Unexpected Benefits

People looking to build muscle know that adding a little extra protein to their diet can help. Your body breaks down protein into amino acids, which it uses to repair and grow muscle tissue. Sure, you could eat several chicken breasts a day to get more protein, but choking down a chicken breast after a tough workout isn't exactly appealing.

That's where protein powders come in handy. Whey protein, in particular, is quickly digested, so it gets to work repairing and building muscle fast. But let's face it — when you mix it with water, the taste can be pretty underwhelming. Mixing your protein powder with milk not only makes it taste better but also gives you an extra protein boost.

A cup of 2% milk adds about 8 grams of protein, but here's what you might not know. Roughly 80% of the protein in cow's milk is casein. Why does that matter? Casein is digested more slowly, which means it keeps delivering those muscle-building amino acids over a longer period of time. In other words, it keeps working long after your shake is gone.

You might not hear as much about casein, but bodybuilders have been using it for years to help prevent muscle breakdown. Since casein is digested more slowly, Muscle and Fitness recommends having it before bedtime. A 2020 review in Physical Activity and Nutrition found that having at least 40 grams of casein about 30 minutes before bed can boost muscle repair, reduce muscle breakdown, and ease soreness by lowering inflammation.

That much casein, though, isn't ideal right after a workout when your muscles are begging for fuel. That's where you need a little more whey. Whey protein gives your body a quick hit of amino acids, especially leucine, to kick-start muscle growth. But the bit of casein you get from milk adds a steady, slow release of amino acids, according to a 2018 review in Frontiers in Nutrition. Not only that, but casein helps keep you feeling fuller if you don't have a proper meal lined up anytime soon. That whey-plus-casein combo from milk isn't just for people lifting weights. Endurance athletes might want to toss some milk into their post-workout routine to help muscles recover faster.

The casein in milk can do your body good in more ways than just building and repairing muscle. According to a 2016 review in the Iranian Journal of Pharmaceutical Research, casein may help protect against colon cancer by working with your gut microbiome. Your teeth might also thank you for casein. Casein can block certain enzymes to make it harder for plaque to build up. Plus, casein helps protect your tooth enamel from the acids in sugary drinks. Some research also shows that supplementing with casein may help lower cholesterol. Casein may even lower your blood pressure.

And let's not forget the other perks of drinking milk every day. A glass of milk gives you almost 300 milligrams of calcium per cup to help keep your bones strong. Milk also provides about 15% of your daily vitamin D, which helps your body absorb calcium and supports your immune system. On top of that, milk is a good source of B vitamins, which support your metabolism and help keep your skin, muscles, and brain healthy. Sure, adding a cup of milk to your protein shake might tack on a little over 100 calories, but the extra protein and nutrients could actually help with weight loss by promoting fat breakdown (per Healthline).