Best protein powder for weight loss: Build & tone muscle without the extra calories

Looking to shed some pounds? Our pick of the best protein powder for weight loss can help you meet your goals

Included in this guide:

Woman drinking a shake made from the best protein powder for weight loss
(Image credit: Getty Images)

The best protein powder for weight loss will often depend upon your individual needs. Generally, you want something high in protein to ensure you build muscle, that is low in calories. But how do protein shakes help weight loss?

Nutritionist and chef Dee Momi explains, "Shakes with a high protein content can rev up your metabolism because of the number of calories needed to digest it - up to 30 per cent of calories from protein are burned compared to around 10 per cent of calories from carbohydrates. High protein drinks also encourage fullness so we feel satisfied, which is essential when trying to lose weight."

"To get the most out of your protein powder, I would suggest treating it like a balanced meal by combining it with carbohydrates and fat - such as frozen bananas, oats, berries, nut butters, avocado or coconut milk - and consuming within 30 minutes after a workout for optimal benefits."  

Whey protein is the most popular variety and is one of the best protein shakes for weight loss. Other types include casein, a protein found in milk that is digested more slowly, and collagen powder which can benefit your skin and bones as well as muscles.

No matter what your protein powder for weight loss needs are, this article will help you wade through all the options to make your decision.

Black Friday protein deals: The best deals live right now

Today's best Protein powder, Optimum Nutrition Gold Standard, PhD Nutrition Diet Whey Protein Powder and SlimFast High Protein Shake Mix deals
Show Filters
Any Price
Sort By

Looking for more stellar bargains on protein powders? Check out our dedicated Black Friday protein deals guide for more.

Our first port of call for the best protein powder for weight loss is Optimum Nutrition Gold Standard Whey Muscle Building and Recovery Protein Powder. It’s one of the best-selling brands on the market for good reason – it’s tasty, effective and good value.

We also love RSP Nutrition AvoCollagen Protein Powder. Crammed with Collagen Peptides, known for its appetite-suppressing properties, and fat-blasting Avocado Oil, it’s a great product for weight loss.

The best protein powder for weight loss you can buy right now

Best protein powder for weight loss: Optimum Nutrition Gold Standard Whey Muscle Building and Recovery Protein Powder

(Image credit: Optimum Nutrition)

1. Optimum Nutrition Gold Standard Whey Muscle Building and Recovery Protein Powder

The best protein powder for weight loss for most people

Fat per 100g: 3.2g
Carbs per 100g: 7.75g
Sugar per 100g: 4.5g
Protein per 100g: 78.5g
Reasons to buy
+Tasty flavour choices+High protein content
Reasons to avoid
-Contains the sweeener acesulfame potassium-Not completely lactose-free 

One of the most popular and well priced on the market, this no-frills protein powder does what it says on the tin. It’s low fat, low sugar and high protein per scoop. It comes in loads of flavours (chocolate lovers are particularly catered for), tastes good, mixes well and has great energy-boosting macronutrients.

What’s more, whey protein has been scientifically proven to aid weight loss – a study of overweight people supplementing their diet with it found that they lost more weight and gained muscle mass than those who didn’t. The same research revealed that whey protein users also enjoyed a reduction in their blood pressure and cholesterol!

Whey is effective in boosting weight loss because of its ability to decrease appetite and make you feel fuller, meaning you’re less likely to overeat.

One potential downside is that this protein powder contains acesulfame potassium (sweetener), said to be 200 times sweeter than sugar - but it's relatively harmless at low levels.

Best protein powder for weight loss: Supreme Nutrition Diet Whey

(Image credit: Supreme Nutrition)

2. Supreme Nutrition Diet Whey

The best premium protein powder

Fat per 100g: 8.5g
Carbs per 100g: 11.5g
Sugar per 100g: 4.6g
Protein per 100g: 69.6g
Reasons to buy
+Full of natural fat-burning ingredients+High protein content
Reasons to avoid
-Slightly lumpy texture-Limited choice of flavours

Supreme Nutrition Diet Whey uses natural fat-blasting ingredients green tea (equivalent to five cups per serving!) and flaxseed to help you reach your weight loss goals.

It’s also low in calories and high in whey protein, which we already know has been proven to help people drop pounds, according to studies. One user said having 2.5 scoops twice a day as a meal replacement had helped them lose 4kg in two weeks!

We tried the strawberries and cream flavour, which wasn't as overly sweet as it might sound. It’s best taken after a workout when the body’s metabolism is lifted, as this makes it easier to absorb. 

With only 123 calories per serving, it’s a good all-rounder for anyone trying to lose weight, stay lean or naturally burn fat.

Best protein powder for weight loss: PhD Nutrition Diet Whey Protein Powder

(Image credit: PhD Nutrition)

3. PhD Nutrition Diet Whey Protein Powder

The best budget protein powder

Fat per 100g: 5.5g
Carbs per 100g: 11g
Sugar per 100g: 5g
Protein per 100g: 68g
Reasons to buy
+Low in carbs and sugar+Good value
Reasons to avoid
-Slightly artificial sweetener aftertaste-Bag can be difficult to seal

Launched in 2010, PhD Diet Whey is one of the original weight loss management shakes, and it’s still going strong - for good reason. This high protein, low carb, low calorie powder is macro-friendly, great for anyone trying to lose weight on the keto diet ,and diabetics too.

It contains added nutrients to help boost fat loss and energy such as green tea (thought to help the body’s metabolism be more efficient), CLA (which helps the body mobilise stored fat), L-carnitine (another metabolism booster that moves more fatty acids into your cells to be burned for energy, increasing your ability to burn fat and lose weight) and flaxseed (the high protein content suppresses appetite and prevents overeating).

It mixes well with no lumps, although can be grainy thanks to the flaxseed. The slow release protein blend helps curb cravings and keeps you full. For sensitive tummies, it also digests very well. Plus it's available in 13 flavours, so you won’t get bored.

Best protein powder for weight loss: RSP Nutrition AvoCollagen Protein Powder with Collagen Peptides and Avocado Oil

(Image credit: RSP Nutrition)

4. RSP Nutrition AvoCollagen Protein Powder

The best protein powder for people wanting to target tummy fat

Fat per 100g: 20g
Carbs per 100g: 20g
Sugar per 100g: 5g
Protein per 100g: 50g
Reasons to buy
+Anti-ageing properties+Bone-building ingredients
Reasons to avoid
-Only three flavours: chocolate, vanilla, unflavoured-Slightly synthetic, bitter aftertaste

This protein powder is just 90 cals per serving and blends collagen and the nutrient powerhouse that is avocado oil – a double whammy of magical ingredients that help the body lose weight faster.

Avocado oil is rich in monounsaturated and oleic fatty acids, which scientists believe can help reduce abdominal fat. People who consumed three tablespoons of high-oleic oils every day for a month reduced belly fat by 1.6 per cent, compared with those who consumer a flax/safflower blend (which is high in polyunsaturated fat), a Penn State study found

Coupled with collagen – known to suppress appetite, increase feelings of fullness and boost metabolism – this is a killer combo. Collagen has the added benefit of minimising wrinkles and fine lines, thickening hair and nails, and the peptides in it are gut-friendly and help bones stay strong

Our only grumble is we’d love some more interesting flavours to choose from, but the chocolate one in particular gets the thumbs up from us.

Best protein powder for weight loss: SlimFast

(Image credit: SlimFast)

5. SlimFast High Protein Shake Powder

The best protein powder for short-term weight loss

Fat per 100g: 1.1g
Carbs per 100g: 13g
Sugar per 100g: 7.6g
Protein per 100g: 5.3g
Reasons to buy
+Inexpensive +Great range of tasty flavours
Reasons to avoid
-Not recommended as a long term use as highly processed-Can cause excess wind

This budget-friendly meal replacement shake comes in six flavours, has no added sugar and every serving is packed with 15g protein and 23 essential vitamins and minerals. 

It's designed to be used as part of the SlimFast 3-2-1 Plan, which involves limiting your diet to three 100-calorie snacks, two SlimFast shakes and one low-calorie (600 or less) meal a day.

Whilst there’s nothing fancy about it, these shakes work well for people who don’t want to count calories and want to lose weight with minimum effort. Studies have shown that people burn fat faster when they eat portion-controlled meals or meal replacements.

The reviews speak for themselves, with one user claiming to have lost 4lbs in two weeks - no wonder it's one of Amazon's best-selling protein powders for weight loss.

If you’re looking for a tried-and-tested method to kick-start your weight loss journey, then SlimFast is a great place to start - although it's not necessarily a great long-term option.

Optimum Nutrition Casein Protein

(Image credit: Optimum Nutrition)

6. Optimum Nutrition Gold Standard Casein Powder

The best protein powder for overnight muscle gain

Fat per 100g: 2.5g
Carbs per 100g: 5.8g
Sugars per 100g: 3.4g
Protein per 100g: 74g
Reasons to buy
+24g of protein+Very little sugar/carbs+Time-release protein, ideal for overnight
Reasons to avoid
-Not good for immediate post-workout consumption or meal replacement

This protein powder is another milk-based powder made from casein protein, a "time-release" protein which is digested slower than whey. This means that protein is slowly absorbed into your muscles rather than being "dumped" all at once. 

Sleep is extremely important for helping your muscles recover after a demanding resistance training session. Drinking a casein shake before bed will aid your muscle's recovery throughout the night – or, in fact, during the day. 

If you're looking for a casein shake, you can't go wrong with the Optimum Nutrition brand. The Gold Standard whey is our all-rounder best shake, and this one is just as good, with a selection of tasty flavours including Chocolate Supreme and Cookies and Cream, very little sugar, few carbs and 24g of slow-release protein per 33g serving. 

Woman and man drinking a shake made from the best protein powder for weight loss

(Image credit: Getty Images)

How to choose the best protein powder for weight loss 

First up, study the ingredients list and nutritional content. Most powders will be high in protein, but if weight loss is your goal ideally you also need a product that is low in sugar and calories.

But of course there’s more to weight loss than just calories – food and its macronutrient composition can influence how hungry or full you are, so just because 100 calories of kale and 100 calories of cake contain the same amount of energy, they affect your body and food choices differently. 

What we mean is in order to lose weight, the protein powder needs to have a balanced macronutrient profile – essentially the right mix of protein, carbs and fat to hit your body goals. Google ‘macro calculator for weight loss’ and you’ll find lots of free online tools to help you work out the right amount of carbs and fat you need to achieve your weight loss goals.

But there’s no need to get too bogged down with your “macro count” as lots of brands pack their powders with natural weight loss-boosting ingredients. If you see green tea, L-carnitine or CLA in the ingredients list, then it’s a good sign.

Let’s not forget the importance of taste. Just because a brand has lots of weight-loss boosting elements, doesn’t mean it’s going to be tasty, or have a good texture. Experiment with flavours and mix it up occasionally so you don’t get bored.

How protein powders work and common misconceptions

Protein, along with carbohydrates and fat, are one of the three main macronutrients that make up everything we eat. Proteins are amino acids which help maintain, build and repair damaged muscle tissue. The more you exercise, and the more you work your muscles, the more protein it's thought you need. 

When we exercise, the reason our muscles get sore is that we create small tears in our muscle fibres. Proteins, which are comprised of amino acids, help mend and repair those tears. Over time, this causes muscles to build up and swell as they're repeatedly used, torn and come back stronger. 

Protein powders are entirely unrelated to steroids: they're not chemicals, but derived from food, whether that's animal products such as whey or a vegetarian alternative such as pea protein. We get protein every day from sources such as meat, eggs, dairy, pulses, legumes, nuts and seeds: protein powder is just a concentrated form of that.

Why do we need protein powders, if we can get everything from food? The American College of Sports Medicine recommends that people who lift weights or does endurance training regularly, such as running or cycling, need between 1.2 or 1.7g of protein per pound of body weight. every day, in order to build muscle and get stronger. That's a lot, and hard to get from three square meals a day. Protein shakes offer a convenient, affordable way to get more protein into our diets.