Protein powders are among the most popular products in the fitness industry.
Studies show that the global protein supplement market size was valued at $17.55 billion in 2019 and $18.91 billion in 2020.
In fact, sports protein powders account for the largest demand in the sports nutrition industry in the US with a market share of over 70%. These products are the most widely consumed nutritional supplement among gym-goers (1, 2, 3).
The high demand for protein powders also propels manufacturers to offer more options and meet the needs of different people.
So if you’re looking for the best low-calorie protein powder this post has got you covered. Scroll down to see the best options on the market, but also to learn more about these products.
Why choose a low-calorie protein powder?
If you are looking for a protein powder to contribute to your weight-loss efforts, the low-calorie option is the way to go.
The reason is simple – this type of protein powder can adequately meet the challenges of a demanding weight-loss journey.
In order to understand the importance of low-calorie protein powder, it’s useful to address the basics of weight loss.
As you can already conclude, weight loss has a lot to do with calories.
Calorie surplus and calorie deficit
Calories are used to measure the amount of energy in a beverage or food.
For men and women who are trying to slim down, keeping track of calorie intake is important.
As much as we’d like to lose weight without even thinking about calories, the reality is that we need to take intake and expenditure of calories into consideration during our journey.
Although calories may seem complicated, they’re quite simple.
Consuming more calories than you burn leads to weight gain. This is called calorie surplus.
On the other hand, consumption of fewer calories than you burn through physical activity puts you in a calorie deficit. As a result, you lose weight.
You burn calories through the following processes:
- Metabolic rate – the body utilizes most of the calories from food to sustain basic functions
- Digestion – in other words, thermic effect of the food (TEF) and it accounts for 10% to 15% of all calories you consume. The percentage here depends on the food you eat
- Physical activity – the remainder of calories you burn accounts for physical activity in total, not just exercise
Various factors influence how many calories you burn during the day.
These include gender, age, height, weight, body fat percentage, physical activity levels, and exercise.
You see, physical activity doesn’t include exercise only. That’s an important confusion we need to clarify.
For most people, being physically active means exercising regularly. Sure, that implies too but physical activity also includes walking and other activities you do instead of being sedentary.
Protein is crucial for weight loss
A well-balanced diet with an adequate intake of nutrients is of huge significance for successful weight loss.
We need adequate amounts of macronutrients as well as vitamins, minerals, and other compounds to ensure our body works properly.
Probably the most significant nutrient for weight loss is protein.
A high intake of protein decreases appetite, accelerates metabolism, and positively influences hormones that regulate weight (6, 7, 8).
Protein helps burn abdominal fat.
Several mechanisms are involved in its role in weight/fat loss, as mentioned already. We’re going to focus on them in more detail below:
- Protein alters levels of some weight-regulating hormones – higher consumption of protein has the potential to increase the concentration of appetite-reducing i.e. satiety hormones such as peptide YY, cholecystokinin, and GLP-1 while decreasing ghrelin levels, the hunger hormone. In other words, upping the intake of protein helps you reduce hunger and increase satiety on a hormonal level.
- Burning more calories – protein has a lot higher TEF than carbs and fats. The thermic effect of protein is around 20% to 30% while carbs are at 5% to 10% and fats are 0% to 3% (9). In fact, thanks to the high thermic effect and some other factors, increased consumption of protein can accelerate metabolism. You burn more calories, even while sleeping (10, 11). What’s more, a higher intake of protein accelerates metabolism and increases the number of calories you burn by 80 to 100 a day (12, 13, 14)
- Reduced appetite – protein makes you feel full for longer and improves your satiety by suppressing appetite. As a result, you consume fewer calories and prevent overeating. All this is important for successful weight loss and its maintenance. Additionally, protein exhibits a powerful effect on cravings, especially for snacks late at night. Since cravings are a major problem for many people who are trying to lose weight, higher protein intake can help take care of this problem
- Weight loss without severe calorie restriction – although calorie deficit is necessary for successful weight loss, you don’t have to starve yourself to slim down. Increased protein intake promotes weight loss even without significant restrictions in calorie intake. That happens because protein influences calories in and calories out alike
- Preventing muscle loss – a common for many people is that they lose weight, but also their muscle mass. This nutrient helps you retain muscle mass while burning fat
As seen above, protein matters a lot for weight loss.
In addition to all these benefits, protein also improves your athletic performance and allows you to get the most from your workout session. Protein also supports muscle recovery.
Low-calorie protein powder gives you the best of both worlds
Now that we’ve established the basics of successful weight loss, it’s easy to understand the reason you need a low-calorie protein powder.
The low-calorie formula of these products supports the efforts to maintain a calorie deficit but eliminates common problems associated with it.
You see, many people choose unhealthy ways to reach and maintain calorie deficits, primarily fad diets.
This move leads to nutritional deficiencies and health problems. On the other hand, low-calorie protein powders help avoid this issue.
Not only do they contribute to your effort to reduce calorie intake, but also deliver all the benefits that protein powders provide. This gives an extra boost to your weight loss.
In other words, one such product supports weight loss and provides all other benefits that protein powders have, but with reduced calorie content.
When it comes to the intake of protein supplements it’s practical to address scientific evidence.
Does the evidence confirm or deny the claims regarding the beneficial effects of these products? Science says they can be quite helpful.
Journal Frontiers in Nutrition published a study that evaluated current evidence of the effectiveness of protein supplementation on muscle protein synthesis.
Findings revealed that both pre- and post-workout supplementation with protein can be effective. Pre-exercise protein intake is useful for optimizing physical performance and positively influences recovery.
Post-workout supplementation yielded superior results, though. Yet another important discovery in this study is that a practice of no food/drink for 60 minutes after the workout isn’t beneficial.
More precisely, failing to feed the body after a workout session has more disadvantages than benefits (15).
A review of studies, published in the Journal of Dietary Supplements, found extension promotion of protein supplements may lead to overconsumption in some persons.
The review emphasizes the importance of obtaining protein from diet primarily. However, protein supplementation is necessary in many cases.
When that happens, a person should still adhere to the dosage instructions to avoid potential side effects from overconsumption (16).
Different types of low-calorie protein powders
Not all protein powders are the same. We can divide them into three main groups based on the type of protein used to make those powders.
These include whey, casein, and plant-based protein. Below, we’re going to focus on each type of low-calorie protein powder.
Whey protein powder
Whey protein is one of the two main proteins in milk and dairy products. The other milk protein is casein, which we will discuss below.
Basically, whey protein is a combination of proteins isolated from whey. And whey here is a liquid part of milk separated in the cheese-making process.
Once separated, whey undergoes several steps to become what people know and use as whey protein today, a powdery product that people use as a meal replacement, add to shakes, and more.
Since whey isn’t usually tasty on its own, many products are flavored.
Whey protein is abundant in amino acids
Probably the most important thing about whey protein is it contains a remarkable “selection” of amino acids which are quickly absorbed.
Amino acids are smaller molecules that are attached one to another in order to build proteins.
While our body produces some of them, other amino acids we obtain from the diet. Those we get from food are called essential amino acids.
The best kinds of proteins are those that deliver all nine essential amino acids, and whey checks that box easily.
Whey is particularly abundant in BCAAs (branched-chain amino acids) such as leucine, but also delivers high levels of cysteine (17).
Leucine is particularly interesting since evidence confirms it is the most anabolic amino acid i.e. it promotes growth.
Types of whey protein
Considering its structure, whey protein is effective at promoting growth, but not all types of this protein on the market at the same.
We can divide them into the following categories:
- Isolate – contains 90% of protein or higher and has lower levels of lactose and fat, as well as some nutrients
- Concentrate – delivers 70% to 80% of protein, but also contains lactose, fat, and some nutrients that isolate lacks. It’s also tastier
- Hydrolysate (hydrolyzed whey) – pre-digested for better and faster absorption. Compared to isolate, hydrolyzed whey causes a 28% to 43% increase in insulin levels
For many people who use whey protein, concentrate is the most useful option.
Not only is it the most affordable, but also comes with some nutrients that are found in whey.
How does whey protein work
Whey protein has become a go-to product for many bodybuilders, athletes, and other active men and women.
They love this protein because it promotes muscle gain and strength. Whey protein exhibits its effects through several mechanisms such as (20, 21, 22):
- Delivers amino acids that promote muscle growth
- Quickly absorbed and used by the body
- Supports the release of anabolic hormones that promote muscle growth e.g. insulin
- Stimulates the synthesis of muscle protein thanks to leucine at both genetic and molecular levels
Additionally, whey protein also works to promote satiety and thereby reduces your appetite.
For that reason, it’s a great option for persons who are trying to lose weight.
Other benefits of whey protein
Even though people use whey protein to increase muscle strength and get more gains, or to support their weight-loss endeavor, this type of protein has many other health benefits.
You see, whey also contains immunoglobulins, lactoferrin, alpha- and beta-lactoglobulin, all of which are proteins with great health potential.
Supplementation with whey protein can lower blood pressure and blood glucose levels, aid stress management, and decrease symptoms of depression.
Additionally, whey may increase bone mineral density and strengthen the immune system.
Casein protein powder
As mentioned above, casein is the other protein in milk and dairy products.
Casein contains about 80% of the protein found in cow’s milk, while the remaining 20% account for whey.
Unlike whey, which is the liquid part of the cheese-making process, casein is actually in the curds.
How is a casein protein powder made?
The best way to understand whey and casein’s origin is to picture cottage cheese. The liquid on top has whey, which was separated from the curds below.
The curds contain casein. This protein is made from skim milk through a process where whey is drained first.
Then, it’s time to wash, drain, and dry the remaining curds and grind them into powder.
Absorption of casein powder
Just like whey, casein is also a complete protein meaning it delivers all essential amino acids. For that reason, casein is a high-quality protein.
Compared to whey and its fast absorption, casein is absorbed more slowly. The reason behind a relatively slow absorption comes down to an acidic environment in the stomach.
In this particular environment, casein becomes gel-like or clots. As a result, the body needs more time to digest and absorb it (23, 24).
Benefits of casein powder
While it’s easy to think slow absorption is a disadvantage of casein, the reality is different. In fact, it offers quite a few benefits such as:
- Muscle growth – muscle-growth effects of casein are similar to those of whey, despite slower absorption, and especially when taken post-workout
- Reduced hunger – like other dairy proteins, casein suppresses appetite and makes you feel full for longer, meaning it’s suitable for persons who are trying to lose weight
- High in nutrients – some casein products are good sources of nutrients such as calcium
You should also bear in mind slower absorption means casein feeds the body with amino acids for a longer period of time.
Types of casein powder
Just like whey, casein comes in different types. Two types of casein are:
- Casein hydrolyzate – predigested and quickly absorbed form of casein
- Micellar casein – digested slowly, but the most popular type of casein protein
Casein is known as an anti-catabolic protein, meaning it helps decrease muscle breakdown.
You see, casein supports protein synthesis even in situations when the body would break down muscles e.g. when you don’t eat for long periods (25, 26).
Other benefits of casein powder
In addition to muscle growth, other benefits of casein include:
- Antibacterial properties
- Immune benefits
- May decrease high blood pressure
- Decreases triglyceride levels
- Antioxidant effects
- Promotes fat loss
IMPORTANT: Some brands combine both whey and casein protein powders in a single product. The goal here is to deliver the benefits of both types of dairy protein.
A combination of whey and casein provides effects such as fast absorption together with slow-releasing protein in a single supplement. In other words, one such product combines anabolic and anti-catabolic effects for better results.
Plant-based protein powder
Even though animal-based proteins are most popular, they may not be suitable for some persons e.g. vegans and vegetarians.
The good thing is that you also have the option to use plant-based protein powders. As you can presume, these products do not contain animal-based ingredients.
Difference between plant- and animal-based protein powders
The biggest difference between plant and animal proteins is their structure. Despite some claims, plant-based proteins are not complete.
In other words, they do not contain all essential amino acids like animal-based proteins such as whey and casein do.
Sources of plant proteins
Different manufacturers use different plant sources in their protein powders. In most cases, these are seeds and legumes.
These protein powders are made by removing most of the carbs and fat while isolating protein.
Some manufacturers use protein from peas, sprouted lentil beans, sprouted navy beans, and cranberry seeds.
Others obtain protein from flaxseeds, quinoa, brown rice, pumpkin, and chia seeds.
It is useful to mention plant protein powders tend to be low in calories.
Not only do they provide all the benefits linked to protein supplementation, but also support weight loss.
Benefits of plant protein powders
Other reasons plant-based protein powders are beneficial include:
- Since they contain no lactose, these products are suitable for persons who experience bloating and gas when consuming whey
- May help tone and build lean muscle while supporting repair and rebuilding of tissue
- Naturally good taste
Consumption of plant-based protein and nutrients improves several health aspects.
For example, plant protein can reduce the risk of heart disease and type 2 diabetes.
The Best Low-Calorie Protein Powders Reviewed
After a detailed insight into the world of protein powders, their types, and benefits it’s time to focus on the best products on the market. Scroll down to see the best low-calorie protein powders.
Best for: Digestive health
Orgain is a well-known brand of protein powders. They rely on clean and healthy nutrition that also happens to taste great. Their whey protein supplement is available in two flavor options such as vanilla bean and creamy chocolate fudge.
The product delivers New Zealand grass-fed whey protein powder that contains 21g of clean and complete protein per serving including 5g of BCAAs.
This protein delivers about 130 calories per serving and it is made without preservatives, additives, soy, and gluten. Delicious protein powder also offers a dose of fiber, calcium, iron, and potassium in each serving. Fiber is particularly significant for its influence on digestion and appetite suppression.
- No additives, gluten, soy
- Also delivers fiber and several minerals
- Pure grass-fed whey protein
- Lower in calories than other options on the market
- Brand offers a discount option for repeated purchases
- No unflavored or unsweetened option
Orgain grass fed whey vanilla bean protein powder is a naturally smooth and delicious nourishment drink with 21g of grass fed whey protein sourced from New Zealand. Gluten free, Kosher, no sugar added, vegetarian, Non-GMO, soy free. No artificial flavors, colors or preservatives.
- 100% New Zealand sourced grass fed whey protein
- No artificial colors, flavors, or preservatives
Best for: Nutrients
Isopure is a brand that focuses on high-quality, premium sports nutrition products. Their Low Carb whey protein delivers 25g of pure whey protein isolate per scoop.
As you can presume from its name, the product delivers protein without packing on the carbs and sugar, thereby helping you control calorie intake. Since it’s low in carbs, this protein powder is suitable for persons who want to lose weight, those on the Keto diet, or some other low-carb eating pattern.
One serving contains only 110 calories, 0.5g fat, and decent values of minerals such as calcium, potassium, magnesium, zinc, selenium, copper, manganese, chromium, among others. It also enriches the body with vitamins including vitamin A, C, K, E, B6, B12, thiamin, and riboflavin. Isopure Low Carb whey protein comes in 13 flavor options, but no unflavored option.
Regular use is dubbed beneficial for muscle building and recovery, weight management, muscle health, and overall nutritional profile. The product doesn’t contain gluten and lactose, or fillers. Customers can also select the size of the container. Options include 1 pound, 3 pounds, and 4.5 pounds containers.
- Pure whey isolate
- Contains a wide range of vitamins and minerals
- Multiple flavor options are available
- No carbs and very low in calories
- No unflavored option
- Contains soy
Pack in powerfully pure protein, without packing on the carbs. Our 100% whey protein isolate powders amp you up, without any unwanted weight. Just pick your level: Zero Carb or Low-Carb (which also has ZERO sugar), both with 25 grams of protein per scoop. It's 100% whey protein isolate loaded with vitamins, minerals and nutrients to keep you going strong—and always without gluten, lactose, or any impurities. Made with our complete microfiltration process to be the only completely clear milk protein when dissolved in water. Available in a range of delicious flavors to mix up some seriously delicious and dynamic recipes. Not a significant source of saturated fat, trans fat, dietary fiber, total sugars, added sugars, vitamin D and iron.
- A high-quality protein source providing 25g per serving to support muscle building and recovery
- Helps for those watching their calorie intakes
Best for: Meal replacement
Founded in 2004, Vega has a mission to improve a customer’s health or performance through plant-based nutrition.
Vega One Organic is a vegan meal replacement shake that delivers 150 calories per scoop.
One serving contains 20g of plant-based protein sourced from pea, sunflower seed, and pumpkin seed. All sources of plant protein used in this product are organic.
Additionally, Vega One Organic also delivers superfoods such as chard, broccoli, kale, spirulina, pomegranate, and blueberries. It’s also a great source of vitamin D, which we usually don’t obtain through diet in sufficient amounts.
One serving of the product also supplies the body with 4-6g of fiber i.e. 16% of the recommended daily intake as well as 500mg of Omega-3 fatty acids. To support your digestion and gut health, Vega One Organic also contains probiotics.
Micronutrients such as vitamins A, C, K, B6, B12, thiamin, niacin, folate, biotin, and minerals like calcium, zinc, phosphorus, iron, magnesium, and manganese are also present in the formula.
- Delivers a wide spectrum of nutrients
- Contains superfoods
- Available in 7 flavors and 4 different sizes
- Plain unsweetened option also available
- Contains more calories than some animal-based proteins on the market
- On the pricier side
Vega One® is all in for organic. Full of real, organic plant-based ingredients, Vega One® Organic All-in-One Shake harnesses the power of plants to help you supercharge your day, deliciously.
- Provides 20g of plant protein and at least 25% of 11
- Good-for-you vitamins and minerals.
Best for: Milkshake lovers
Quest is on the mission to make foods you crave work for you, not against you.
In other words, they create delicious products with complete protein and with minimal levels of sugar and carbs. Their protein powder contains 110 calories per serving.
It delivers a blend of proteins such as whey protein isolate, micellar casein, and milk protein isolate.
One serving of this product contains 3g or 1% of carbohydrates and 22g of proteins. Additionally, one serving also delivers 1g of fiber. Quest Protein Powder is suitable for persons who are looking for a blend of proteins, but also for those who love different flavors.
In terms of flavors, there are 9 options to choose from including chocolate, salted caramel, vanilla, just to name a few.Each item is available in packaging of 3 pounds and 1.6 pounds.
- Good flavor
- Protein blend delivers whey and casein
- Low in calories
- Also contains iron, calcium, potassium
- No soy or gluten
- 0% of added sugar
- Contains milk
The new 1.6 lb canisters of Quest Protein Powder are the perfect size to stack in the cabinet or toss in your bag. It goes where you go, so don't go without your fauorite protein powder!
- Powder is made with 60% fast absorbing Whey Protein Isolate and 40% slow absorbing Micellar Casein
- Enjoy the creamy and rewarding taste of a vanilla shake with 1g of sugar
Best Vegan Low-Calorie Protein Powder
Even though most protein powders on the market are animal-based, there are many vegan alternatives.
Below is the best vegan low-calorie protein powder you can find on the market today.
Best for: Unflavored, vegans
Genuine Health is a type of brand that focuses on vegan and plant-based products primarily. They use the purest and highest quality ingredients from natural and sustainable sources.
When it comes to protein powders, Genuine Health has three options: unflavored, chocolate, and vanilla flavors.
While one scoop of unflavored protein powder has 100 calories, chocolate and vanilla contain 120 calories.
In other words, all three options are low-calorie protein powders that may support your weight-loss endeavor. One serving of the protein powder supplies the body with 20g of protein, 2g of fat, and 0g of added sugars if you choose an unflavored option.
The other two options have pretty much the same structure but 4-5g of carbs, unlike unflavored protein powder that delivers 2g of carbohydrates.
Protein for this product is obtained from seven plant-based sources such as organic spirulina, mung bean, pumpkin, yellow pea kernel, flaxseed, brown rice, and hemp.
Considering the fact plant-based proteins are not easy to digest, the brand ferments their protein in batches with non-dairy probiotics and enzymes. That’s why this protein powder doesn’t cause bloating.
- Unflavored option available
- Low in calories
- No sweeteners and artificial flavoring
- No option to choose bigger or smaller packaging
Get more from your protein. Only fermented organic vegan proteins+ gives you a more digestible protein with a balanced amino acid profile – and gut health benefits! Made with a custom blend of 7 high protein vegan ingredients – organic spirulina, organic mung bean, organic yellow pea kernel, organic pumpkin, organic flaxseed, organic hemp and organic brown rice – that provide a balanced amino acid profile.
- Features a full spectrum of amino acids from 7 plant based sources and fermented fiber
- Vegan, Non GMO, Gluten Free, Dairy Free, and free of Artificial Flavors and Colors
Products to avoid
Not all protein powders are equally beneficial for your needs.
When you’re looking for a protein powder that will benefit your weight loss, you may avoid the following.
Why avoid this product?
We’re not saying Optimum Nutrition Serious Mass Weight Gainer is bad in terms of quality.
However, if you’re looking for a low-calorie protein powder this is not it. This product delivers over 1000 calories per serving.
In other words, this protein powder is formulated to increase protein intake and support weight gain, not weight loss. So if you buy this, you would end up in calorie surplus, not calorie deficit.
What to look for in a protein shake for weight loss
Not every protein shake on the market is the best option for weight loss.
Several factors can help you narrow down the choice and find the best product for your needs. They include:
- Calorie content – since we’re talking about weight loss here, the first thing to consider is the number of calories per scoop. Make sure to calculate how many calories you eat per day, on average. This will help you determine the ideal calorie content in a protein powder. In most cases, the ideal number is up to 120 calories per scoop
- Source of protein – think about your needs and lifestyle to determine whether you should go for plant- or animal-based protein. There is no right or wrong answer here since this is a personal choice
- Natural structure – ideally, you should go for protein powders that are natural and without artificial ingredients like flavoring. Now don’t get this confused with flavored protein powders, which dominate the market. Many brands use natural sources to add flavor. So that’s why you should check whether the manufacturer uses natural or artificial flavoring in their product
- No sugar – bearing in mind your goal is to reduce calorie intake and you’re looking for a low-calorie protein powder, you should opt for a product that contains no sugar. Otherwise, sugar would just increase calorie intake and jeopardize your weight-loss efforts
- Brand – nowadays the market is swamped with all sorts of protein powders made by different brands. Not all of them are equally beneficial for your weight loss. For that reason, you should focus on the brand and determine whether they’re reliable or not
- User experiences – you may want to check what other customers said about the product. Did it help them slim down? Did they have a positive or negative experience? While you shouldn’t blindly follow someone’s words, these reviews and testimonials can give you more info about the product, info from a different perspective
Does whey isolate have fewer calories than regular protein powder?
Generally speaking, whey isolate protein powders do contain fewer calories than regular protein powders.
They are also lower in carbohydrates, fat, cholesterol than concentrates. One scoop of whey isolate protein powder has about 110 calories (30).
On the other hand, unflavored whey concentrate delivers about 123 calories per scoop (31). Flavored whey concentrates are higher in calories.
Best time to drink protein powder for weight loss
The best time to drink protein powder for weight loss is in the morning.
Since protein is crucial for fat loss and appetite control, it could help you start a day with a metabolism boost and also make you feel full for longer. That way, you may eat less during the day.
Basically, it’s convenient to drink protein powder shake between meals e.g. to bridge the gap between breakfast and lunch or lunch and dinner.
This practice prevents frequent (and unhealthy) snacking and gives you more control of what you eat. Of course, drinking a protein shake after a workout is also a good idea to support the recovery process and decrease hunger (32).
Protein powders have the amazing potential to support weight loss while toning and improving muscle mass or strength.
Low-calorie protein powders are particularly useful since they allow you to maintain calorie deficit without nutritional deficiencies.
In this post, we’ve discussed different products on the market and provided useful info about protein powders.
Now you just have to think about your goals and find the right product to match your needs. Best of luck.
Dr. Ahmed Zayed holds a bachelor’s degree in medicine from Alexandria university and is a practicing plastic surgeon. He’s our expert on all things nutrition, medicine, rehabilitation, and flexibility. Dr.Ahmed has been a medical content writer for more than 11 years and his work reached top publications such as the HuffingtonPost