Protein smoothies have been popular for years, and they certainly aren’t going away anytime soon. You can make your own protein smoothie at home, or for those of us who are always on the run, can buy pre-bottled varieties. What’s behind their popularity? It’s simple: the pairing of satiating, muscle-supporting protein combined with the benefits of fiber- and antioxidant-rich fruit makes for an unbeatable combination.
“Protein is essential to a person’s health for a multitude of reasons including growth and development in children. It is key for healthy cartilage, skin, and bones, helps with muscle repair after exercise, increases satiety and thermogenesis: the process of heating your body,” explains Aimee Plauche, RD, LDN with Nutritional Wellness Consulting and an advisor for ICONIC Protein. “Your body actually heats up more during digestion of protein than it does when digesting carbohydrate and fat, thus burning more calories.”
While protein smoothies are generally healthy (as long as they aren’t packed with tons of sugar), what you may not know is what’s actually happening to your body as soon as you take that first protein-packed sip. And even though your body may react differently to varying protein sources (there are countless ways to add protein to smoothies, from yogurt to protein powder), there are several things that are bound to occur regardless of the protein source.
Want to know exactly how a protein smoothie impacts your body? Read on, and for more on healthy eating, don’t miss What Happens to Your Body When You Drink a Smoothie Every Day.
“When you drink a protein smoothie with fruit, you will immediately replenish your body with much-needed nutrients, but also you may experience a rise in blood sugar,” says Rachel McBryan, RD, a registered dietitian with the College of Dietitians of British Columbia. This is because fruit tends to contain plenty of natural sugar.
In an effort to curb any harmful blood sugar spikes, which have been associated with weight gain, McBryan says that drinking a protein smoothie can solve this problem. “When you add a source of protein, like from yogurt or protein supplements, what will happen to your body is it will slow the absorption of the fruit sugar and not cause a rise in blood sugar. This is especially important for people with prediabetes or diabetes.”
“Adding a protein source such as protein powder or low-fat Greek yogurt will more than likely make that fruit smoothie last longer from an appetite perspective. Physiologically, protein takes longer to digest, and therefore many individuals find that they feel full for a longer period of time after consuming protein,” explains Mary Wirtz, MS, RDN, CSSD, and a nutritional consultant at Mom Loves Best.
“I encourage clients to always add fiber, such as a fruit and/or vegetables, in addition to a protein in their smoothie, as it is a portable, well-balanced meal on the go,” she adds.
Mackenzie Burgess, RDN, a registered dietitian nutritionist and recipe developer at Cheerful Choices, agrees that protein smoothies boost satiety. “Protein smoothies are a great option to help you feel satisfied and fuller for longer,” she says. “More specifically when looking at the body, protein can help reduce our hunger hormone, also known as ghrelin, and boost our satiety.”
There’s a reason why many people love to sip on a protein smoothie either before or after they hit the gym — studies show that drinks loaded with protein can help prevent muscle damage and aid muscle recovery.
“There is robust evidence that shows that consuming protein (via a smoothie) pre-and/or post-workout induces a significant rise in muscle protein synthesis,” explains Dr. Rashmi Byakodi, a health and wellness writer and the editor of Best for Nutrition.
“Milk-based protein supplementation helps in the attenuation of protein degradation and (or) an increase in protein synthesis that would limit the consequential effects of exercise-induced muscle damage.”
She adds: “Another study has indicated that whey protein ingestion enhances whole-body protein balance and recovery of exercise performance during overnight 10 hours and 24 hours recovery during resistance exercise. It enhances whole-body anabolism and improves acute recovery of exercise performance after a strenuous bout of resistance exercise.”
“Whey-containing protein powder supplements are rapidly digested in the GI tract and branched-chain amino acids or BCAA’s (the building blocks of proteins) are quickly absorbed. This is important when someone is looking to get protein into the muscles quickly for muscle repair,” says Plauche.
“You can help boost your weight loss efforts,” notes Trista Best, RD, a registered dietitian at Balance One Supplements. “For those with a significant amount of weight to lose, protein powder (added to a smoothie) can help to replace protein foods that are typically high in saturated fat and calories, like hamburgers and fried animal proteins.”
To help slow digestion and keep you feeling fuller for longer—both important for weight loss—Plauce says whey protein supplements, especially those that contain casein protein, shine.
“Casein and whey are both rich sources of peptides that significantly decrease blood pressure, contribute to satiety, and help regulate food intake. The casein and whey combo does a body good by helping to achieve and maintain a healthy body weight, improve body composition, and can play a role in the treatment of obesity,” says Plauce.
“Another thing that will happen to your body is that you could gain weight more easily because you may drink more calories than you need because you will not activate the stretch receptors in the stomach, as when the same foods are eaten with less food processing,” says McBryan. “That is, it is better to eat your fruit and yogurt without blending it first.” If that’s more your speed, see these 14 Easiest Breakfast Ideas That Aren’t Cereal.