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12 Of The Unhealthiest Store-Bought Protein Shakes

If you're trying to get more protein in your diet, store-bought protein shakes are an easy option. They're quick, convenient, and easy to consume, especially on the go. Whether you just left the gym or are simply trying to hit your daily protein goals, eating enough of this macronutrient is crucial for optimal health.

Protein plays an important role in many bodily functions. It isn't just about getting buff — protein also helps you maintain current muscle mass and heal from injuries. It's the building block of not only muscles, but bones, skin, and other tissues. Plus, it supports enzyme production, hormone regulation, and immune function. And if you're concerned about your protein intake, you're already thinking about your health. However, not all protein shakes are created equal, and some might actually hinder rather than help your health goals.

Regardless of your motivation, there are certain ingredients in protein shakes that we consider unhealthy across the board. For example, excess sugar or sodium along with chemicals proven to have harmful side effects. To determine which protein shakes were the unhealthiest, we reviewed many nutritional labels and gathered those that fit our criteria. So if you're trying to be healthy and eat enough protein, you've come to the right place. Keep reading for the 12 unhealthiest protein shakes on store shelves.

Bolthouse Farms Protein Plus

Although Bolthouse Farms Protein Plus is packed with vitamins, minerals, and protein, it also has a hefty amount of calories and sugar. One bottle of the brand's Nut Butter Chocolate Peanut Butter contains a whopping 400 calories, 30 grams of protein, and 33 grams of sugar. However, what really caught us off-guard was the 590 mg of sodium, more than a quarter of the recommended amount.

Sodium is an essential electrolyte needed to maintain proper muscle and nerve function, but too much can have adverse effects. According to the Harvard T.H. Chan School of Health, consuming too much sodium puts stress on your kidneys. In an attempt to filter excess sodium from blood, the body holds onto water and increases blood volume, which can ultimately lead to blood pressure and cardiovascular issues over time.

If you're concerned about sodium intake, we'd avoid the Chocolate Peanut Butter variety. Opt for the brand's other flavors, including Vanilla Bean, Strawberry, and Coffee which have far less sodium, ranging from 10-16% of the recommended daily amount. Bolthouse Farms Protein Plus beverages should be easy to find in the refrigerated section of your local store. But mind you, all varieties still contain high amounts of calories and sugar, so be prepared to load up on carbs alongside that protein.

Isopure 32G Protein

Most store-bought protein shakes have a creamy base, with rich flavors like chocolate, caramel, or peanut butter. But often, after a workout, we crave something light and refreshing. If that sounds like you, this is a good alternative. Isopure 32G Protein is available in fruity flavors like Apple Melon, Blue Raspberry, and Grape Frost. All of these clear flavors come in 16-ounce bottles with zero carbs, zero fat, and — you guessed it — 32 grams of protein. But sadly, to get those fun, fruity colors, the company uses artificial coloring and it seems that tasting the rainbow has its consequences.  

A review in the International Journal of Occupational and Environmental Health found that all dyes approved in the U.S. had negative health effects. Isopure's Alpine Punch and Grape Frost use Red 40, frequently contaminated with carcinogens, while the Green Tea Lemon contains yellow 5, a chemical that tested positive for genotoxicity (albeit in non-human studies). Genotoxicity is just as it sounds — it has the potential to change genetic information, which can lead to cancer or autoimmune issues.  

Unfortunately, the list of Isopure's food dyes doesn't end there. So if you want to avoid them, go for the brand's Lemonade. This flavor is essentially colorless, and therefore free from artificial colorings. However, just like all the other flavors, it does contain Polysorbate 80, which is thought to cause digestive distress and liver toxicity, per a study in Advances in Therapy.

Premier Protein

If you need to eat more protein, Premier Protein shakes make it easy. With flavors like Salted Caramel Popcorn and Winter Chocolate Mint, it's no wonder the company has won gold medals in taste awards. Their 11-ounce bottles are packed with 30 grams of protein, but only contain 160 calories and one gram of sugar. So how do they create such a deliciously sweet flavor with such few calories and sugar? The answer is artificial sweeteners including sucralose and acesulfame potassium. 

Acesulfame potassium is in heaps of products, from gums and candy to low-calorie sodas. When something is this ubiquitous, you can't help but assume it's not all that bad. However, there's a lot we don't know about the effects of acesulfame potassium, and the more we uncover, the more dangerous it seems. The researchers behind a study in the Journal of Gastroenterology and Hepatology warned that this chemical is not as safe as we may think. Although the study was done on mice, the results were alarming enough for humans to be concerned. It found that acesulfame potassium had an inflammatory effect and caused serious digestive disturbances, including dysbiosis and intestinal injury. 

Acesulfame potassium also sends a flood of lymphocytes to the intestines. According to the Mayo Clinic, increased lymphocytes generally point to an infection or illness. The body is clearly picking up on something undesirable after consuming this artificial sweetener. Although we can't be entirely sure how people will respond, we wouldn't risk it.

Optimum High Protein Shake

Everyone has different ideas of what they'd consider healthy. If you're trying to consume less sugar, many of these protein shakes fit the bill, including Optimum Nutrition's High Protein Shakes. These drinks come in Chocolate, Strawberry, and Vanilla and contain 161-168 calories, 25 grams of protein, and 13 grams of sugar per 11-ounce bottle. the sugar content isn't what we'd consider super high, but sugar isn't the only thing to look out for when trying to be healthy. 

Optimum High Protein Shakes also contain sucralose, a synthetic sweetener. The Journal of Toxicology and Environmental Health published an overview of the effects of sucralose which presented some disturbing conclusions. Researchers found sucralose altered the gut microbiome in several ways. Some might think sucralose is a low-calorie sweetener so it wouldn't impact one's blood sugar. However, the overview discovered sucralose did indeed alter glucose and insulin levels in the blood. The report also highlighted studies on mice that showed sucralose caused a decrease in beneficial gut bacteria. If Hippocrates was right and disease does begin in the gut, sucralose isn't helping the issue.

Don't Quit Clean Sports Protein

Don't Quit Clean Sports Protein drinks might not be as clean as they sound. These products come in Rich Chocolate, Smooth Vanilla, and Cookies & Cream, and each 12-ounce bottle has 150 calories and 33 grams of protein. This product does get bonus points for using natural low-calorie sweeteners like stevia and monk fruit extract, but on the ingredients label, we also discovered tripotassium phosphate, a potentially harmful food additive. 

A study published in Deutsches Ärzteblatt International found that phosphates used as food additives had a very different effect on the body than natural phosphates. Naturally occurring phosphates in food sources don't pose a health risk since they aren't fully absorbed in the intestine. However, phosphate additives, like the tripotassium phosphate in this protein shake, have a far higher absorption rate, which can bring phosphate levels too high. As the study suggests, this can exacerbate kidney problems and lead to vascular issues.

PediaSure SideKicks

Are your kids picky eaters? The PediaSure company sees you. It's created a line of kid-friendly, protein shakes called SideKicks so children can have a balanced diet, even if they're fussy about food. These beverages are exclusively available at Target and Walmart and each 8-ounce bottle contains 180 calories, 6 grams of fat, 23 grams of carbohydrates, and 10 grams of protein. The macronutrient balance is solid, but we wouldn't consider it a healthy kids' drink, especially with the unhealthy ingredients on the nutrition label. 

Sugar is listed second and corn maltodextrin is sixth. We've all heard the dangers of sugar, but maltodextrin is one of those confusing ingredients that slip under the radar. You may not be sure if it's good or bad because you might not know what it is to begin with. Maltodextrin is used as a thickening agent in food, giving these protein shakes that dense, creamy consistency we love. It also prevents pathogens and mold from growing on food to preserve its shelf life. Although these are both good things, this ingredient also has its cons. According to a study in PLOS ONE, maltodextrin prevents healthy bacteria from growing in the gut. It can also increase E. coli production and lead to other diseases, including Crohn's. To make matters worse, maltodextrin has a glycemic index (GI) of 106-136, which is even higher than table sugar (per Healthline). So although your kids might be getting protein, their blood sugar levels will take a hit.

Nesquick Protein Power

The popular chocolate milk brand Nesquick has jumped on the protein shake bandwagon. To appeal to more health-conscious consumers and fitness enthusiasts, Nestlé created its Protein Power beverage. The drink comes in flavors including Strawberry and Chocolate and is available at major retailers across the States, including Walmart and Amazon. Each 14-ounce bottle has 290 calories, 23 grams of protein, and a whopping 38-39 grams of sugar — higher than any other beverage on this list.

People aren't typically aware of just how much sugar sneaks into their diet through processed food or how damaging it can be. As Dr. Hu explains to Harvard Health, "The effects of added sugar intake — higher blood pressure, inflammation, weight gain, diabetes, and fatty liver disease — are all linked to an increased risk for heart attack and stroke." The American Heart Association recommends adults consume no more than 6% of their daily diet from added sugars. That's 30 grams if you're following a 2,000-calorie diet. Nestle's Protein Power drinks in Chocolate and Strawberry have 18 and 19 grams of added sugar respectively, leaving little room for more. Considering how addictive sugar can be, it's highly likely people will go over their limit.   

Grenade Protein Shake

Grenade Protein Shakes are known for being a high-protein low-sugar option. The company offers many tasty flavors. If you're a chocolate fanatic, you may have tried the White Chocolate, Fudge Brownie, or Chocolate Mint. Meanwhile, fruity fans might prefer the Strawberries and Cream or Banana Armour. Shakes are available in various sizes, with 11-ounce bottles containing roughly 200 calories and 25 grams of protein. These shakes don't contain much sugar, but they do have artificial sweeteners and preservatives. 

However, we chose to single out Grenade Protein Shakes for what they don't have. Despite the unhealthy aspects of the other protein shakes on this list, the majority have significant vitamins and minerals. Meanwhile, Grenade shakes lack many of these micronutrients in their listed nutritional information. If your primary goal is increasing protein intake, these drinks could be the answer — but don't forget to eat things that are considered whole foods to get all the other nutrients you need.

Slimfast High Protein Shakes

Do you remember the Slimfast craze of the 80s? If not, here's the skinny: These beverages were meant to replace meals. You'd have one for breakfast and one for lunch, and follow it up with a well-balanced dinner. The company is still in business today and has expanded to appeal to a wider audience, particularly those aiming to increase their protein intake. Slimfast now carries high-protein shakes in Creamy Chocolate, Vanilla Cream, and Strawberries and Cream flavors. These 11-ounce beverages have 180 calories and 20 grams of protein. Although still marketed as a meal replacement, we'd consider these more of a high-protein snack for busy days. And while the ingredient list does include several vitamins and minerals, it also has different preservatives and additives depending on the flavor. 

The Creamy Chocolate variety contains caramel color, which gives it that deep brown hue you'd expect from cacao. But unlike real cacao, caramel coloring comes with some nasty side effects. The manufacturing of caramel coloring often produces 4-methylimidazole (4-MEI), a known carcinogen (per Nutrition Facts). In a study published by PLoS ONE, researchers encouraged federal lawmakers to regulate beverages containing caramel color. The hope is to reduce exposure to 4-MEI. Currently though, you won't find warnings for caramel coloring on drinks — so make sure to read those nutrition labels.

SIXSTAR Kellogg's Froot Loops Protein Shake

"Follow your nose! It always knows!" If you're searching for that fruity flavor, Toucan Sam's got you covered. Kellogg's Froot Loops and SIXSTAR teamed up to create a high-protein shake. Available at Sam's Club, these 11-ounce drinks offer 160 calories and 30 grams of protein. But be warned, they contain several additives and preservatives including sodium hexametaphosphate. 

Sodium hexametaphosphate preserves food's shelf life and improves its color, texture, and flavor. However, a study in ACS Omega showed that this common preservative interfered with digestion. In the study, sodium hexametaphosphate denatured protein, changing its chemical structure and making it harder to absorb. The study used egg white protein while SIXSTAR's Froot Loops shake uses milk protein, but if this chemical has the same effect across all proteins, its bad news for those tracking their protein intake. On paper, you might be getting plenty of this healthy macronutrient, but whether or not your body is absorbing it effectively is another story.

Muscle Milk Zero

Muscle Milk Zero is the go-to beverage for people avoiding sugar. Flavors include some of the classics, like Chocolate and Vanilla Crème. All varieties come in an 11-ounce bottle with just 100 calories, 20 grams of protein, and — as the name suggests — zero sugar. However, it has a long list of additives, including artificial flavors and sweeteners, preservatives, and additives. One of these additives is carrageenan, which has been associated with cancer-promoting effects.

An Environmental Health Perspectives review noted that researchers back in the 1980s found enough evidence to identify carrageenan as a significant carcinogenic risk. However, this thickening agent is still widely used in dairy and meat products today. More specifically, the review found several studies showing a link between carrageenan consumption and intestinal ulcerations and neoplasms. For us non-science majors, neoplasms are growths of abnormal tissue masses. They can be benign or malignant, but either way, they sound less than ideal. Sadly, it's also present in Muscle Milk's GENUINE and PRO Advanced protein shakes. Luckily, the brand's plant-based shakes are carrageenan-free. So to lower your cancer risk, we'd stick with this option.

Boost High Protein

Boost has 250 calories and 20 grams of protein in just an 8-ounce bottle — one of the smallest on this list. It's no surprise this drink tastes sweet, seeing how it contains glucose syrup, sugar, and stevia. That's quite the trifecta of sweeteners, which probably contributes to that hyper-palatable flavor. Unfortunately, food and beverages that taste this sweet often make you crave more, so even if you're satiated protein-wise, you might reach for another bottle, upping your total caloric intake.

Three sweeteners seems a bit overkill to us, especially because a couple of the ones listed can raise insulin levels. It's well-established that added sugar raises blood sugar levels, but glucose syrup may be less familiar. Glucose is a different kind of sugar with a much higher glycemic index. It's also simpler, so your body absorbs it more quickly. According to the Centers for Disease Control, constantly consuming sugar can wreak havoc on blood sugar levels and cause insulin resistance over time. In addition, a study in Open Heart says that added sugars are a leading cause of coronary heart disease. To keep your blood sugar regulated and your heart strong, we'd watch that sugar intake, starting with which protein shakes you choose.

Methodology

To compile this list, we compared the nutrition facts and ingredients of dozens of store-bought protein shakes. We used our own background in nutritional therapy and researched scientific studies to understand the health benefits and risks of these ingredients. Certain protein shakes stood out to us because they had harmful chemicals or excessive amounts of sugar, calories, or sodium. So, we gathered these unhealthy protein shakes and highlighted exactly why they made the cut.