CHEAPEST
Choose size
22.5g
92
0.4g
0.4g
Weight loss
Low-Calorie Protein Powder for Weight Loss
Compare lower-calorie options by price and nutrition.
Quick filters
HIGHEST PROTEIN %
Size
5kg
22.8g
93
0.3g
0.5g
Size
5kg
17.5g
93
1.5g
1.3g
Choose size
21g
90
1.2g
0.3g
Choose size
17.8g
98
2.3g
1.9g
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19g
99
2g
1.4g
CHEAPEST
Size
5kg
18g
95
3g
1g
Size
4kg
18g
95
2.5g
1.3g
Choose size
20.5g
89
1.4g
0.3g
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21g
89
0.7g
0.2g
Choose size
21g
90
0.4g
0.2g
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19g
89
2.5g
0.4g
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19.5g
95
1g
1.4g
Choose size
19.8g
90
1.4g
0.7g
Choose size
20.3g
98
1.6g
1g
CHEAPEST
Size
5kg
19.1g
91
0.5g
0.3g
Choose size
20.8g
95
1.5g
0.6g
Choose size
19g
97
0.7g
1.8g
Size
1kg
20g
94
1g
0.9g
Size
1kg
17.5g
95
2.5g
1.5g
Size
1kg
21g
95
0.3g
1.1g
Size
900g
18g
93
1.3g
1.6g
Size
1.8kg
20.5g
89
1.6g
0.7g
Size
1kg
20g
93
1g
0.8g
Browse All Weight-Loss Picks (185)
Best Protein for Weight Loss
Not every protein powder is ideal for weight loss. Mass gainers are loaded with carbohydrates. Some concentrates have more filler than protein. This page filters out the noise and shows only products that meet a clear standard: at least 70g of protein per 100g of powder and under 400 calories per 100g.
These are the products that give you the most protein for the fewest calories - the metric that actually matters when you are in a calorie deficit. Whey isolate dominates this list for good reason: it is the most protein-dense type of powder with the least fat and carbohydrate.
All products are ranked by protein-to-calorie ratio, with the most efficient options at the top. We read every price from the retailer’s own page and re-check it daily. Use the filters to narrow by brand, size or specific protein type.
Compare by type
Shop by goal
Pick a target, see the shortlist.
Brand battles
Two brands, one clear winner.
MyproteinBulk
The UK's two biggest DTC brands, head-to-head
ONMyprotein
Premium global vs budget UK favourite
MyproteinProtein Works
Impact Whey vs Whey 80, cheapest per 25g
Power users
Advanced comparison: every product, filteredDense table view with every product, full filter sidebar, and no editorial surfaces.
Methodology
How we rank every bag.
Independent and transparent. Every price is read from the retailer's own page and checked daily. Here's what goes into each score.
01
Cost normalised to £/25g
Every bag divided by its true protein weight, so you see the real cost of a scoop across any size or brand.
02
Protein density, measured
Protein per 100g from the product's own nutrition panel, so a 90% isolate and a 72% concentrate are never compared on bag price alone.
03
Real prices, checked daily
Prices come from the retailer's own listing, never an RRP, and we re-check them every day rather than leaving a feed to drift.
04
No sponsored placements
Rank order is cost per 25g of protein. Some outbound links earn commission; none of them buy a position in the table.
Questions, answered.
Whey protein isolate is typically the best choice for weight loss. It delivers 85-92g of protein per 100g with minimal fat and carbohydrate, keeping calories low while maximising satiety. Clear whey is another good option - it has a similar profile and mixes like juice instead of a milkshake.
Most evidence supports 1.2-1.6g of protein per kilogram of body weight per day during a calorie deficit. This helps preserve muscle mass while losing fat. A single scoop of whey isolate provides around 25g of protein in roughly 100 calories - an efficient way to hit your target.
Yes, some vegan protein isolates (especially soy and pea) hit the same high-protein, low-calorie profile as whey isolate. Blended plant proteins tend to have slightly higher calories but can still be effective - the filter on this page keeps only plant options that meet the 70g+ protein / under 400 kcal threshold.