The Refrigeration Rule You Must Follow For Protein Shakes

All hail protein, AKA the mighty macronutrient that plays a pivotal role in repairing the body's cells and making new ones. Sufficient protein intake helps keep your bones, muscles, and tissues healthy — but did you know that your hair, skin, and even nails rely on protein? Moreover, not getting enough of the highly complex substance could lead to muscle loss or health complications, such as edema, fatty liver, weaker bones, and impaired immune function, per Healthline. It's no wonder why many health-conscious people eat a high-protein diet, starring lean meats, poultry, fish, dairy, and beans. For an extra boost, time-strapped eaters may opt for convenient protein shakes. 

Gone are the days when protein shakes were the accessory of choice for athletes and bodybuilders only. Nowadays, the on-the-go beverages are also embraced by gym enthusiasts, vegetarians, vegans, older adults, and people who want to gain or lose weight. That being said, it is possible to eat too much protein, so it's important to know how much your body needs and not overdo it. Already feeling the urge to prep tomorrow morning's protein shake? Busy souls who want to save time by mixing up their pre-gym fuel in advance can certainly refrigerate it overnight — but only if they follow one important refrigeration rule.

How long can you refrigerate a protein shake?

There isn't much to feel concerned about when pre-mixing a protein shake the night before, as there won't be a significant change in its integrity or nutritional benefits. Registered dietitian and author of "The Superfood Swap" Dawn Jackson Blatner told Men's Journal that a blended protein shake is safe to consume for up to 72 hours if refrigerated. "However," she added, "because separation happens, you'll need to re-blend or shake before drinking." 

Another caveat: Leaving your protein shake in the fridge overnight might not be a good idea if you throw in fruits to enhance the taste, Blatner says. For instance, if you add bananas, the oxidation process could make the shake turn brown and make it seem less fresh. Additionally, you might want to avoid refrigerating your protein shake if you've added creatine monohydrate to the blend. Creatine, when mixed with liquid (such as water or milk), can become "unstable" after some time (via Mindsets and Reps). When in doubt, just shake the bottle to re-mix any loose powder.

If, instead, you're productive enough in the morning to make a shake from scratch and let it sit on the counter while you scamper around the house, make sure to drink it within two hours for food safety. Otherwise, you can always opt for more convenience by purchasing store-bought shakes that are designed to be kept for longer periods, like Cinnabon's new protein drinks.