Protein Powder Types Compared

Typical figures for a 30g scoop. Protein content varies between products, so check your tub's label.

The most common and usually the cheapest powder. Whey is a complete protein, digests quickly and is the richest of the common powders in leucine, the amino acid most closely linked to starting muscle protein synthesis [1][2]. Concentrate keeps some of milk's lactose and fat, so it has a little less protein per scoop than isolate. Most people who tolerate dairy do fine on it.

Isolate is filtered further to remove most of the lactose and fat, so each scoop carries more protein. It's the usual pick if dairy upsets your stomach, or if you want the most protein for the fewest calories. It costs more than concentrate, and for people who handle lactose fine the difference in results is small.

The other main milk protein. Casein digests slowly, releasing amino acids over several hours rather than all at once, while whey peaks quickly [3]. That makes it a common choice before bed or before a long gap between meals. It's a complete protein but contains some lactose.

The most established plant protein powder, and a complete protein. In research comparing whey, soy and casein, soy sat in between the two milk proteins for its effect on muscle protein synthesis [3]. It suits vegans and anyone avoiding dairy, but not people with a soy allergy.

Popular, dairy-free and soy-free. Pea protein is relatively low in methionine, one of the essential amino acids, and plant proteins generally carry less leucine than whey [2]. That doesn't make it a bad choice: a slightly larger serve, or pairing it with other protein foods across the day, closes most of the gap [1].

Blends exist to fill each other's gaps. Pea is low in methionine, while rice is low in lysine, an amino acid pea has plenty of. Combined, they give a more complete amino acid profile than either alone [2]. If you want a plant powder and aren't using soy, a blend is usually the better option than a single source.

Collagen is high in protein on the label, but it's an incomplete protein: it contains no tryptophan and very little leucine. In a study of older women, whey increased muscle protein synthesis while collagen did not [4].

Collagen grams still count toward your daily protein total, but it shouldn't be your main protein source if muscle is the goal. Some powders sold as “beef protein isolate” are largely collagen too, so check the label.

• Most people: whey concentrate. It's complete, high in leucine and good value.
• Dairy upsets your stomach: whey isolate, or a plant powder if isolate still doesn't agree with you.
• Vegan or plant-based: soy, or a pea and rice blend.
• Long gap until your next meal: casein.
• Building muscle: any complete protein works. Collagen shouldn't be your main source [4].
• Watching calories: isolate gives the most protein per calorie, but whole foods like Greek yoghurt and cottage cheese do a similar job.

No. Powder is a convenience, not a requirement. Most active people do well on about 1.4–2.0g of protein per kg of body weight a day, spread across meals of roughly 20–40g each [1], and food can cover that. Powder helps when you're short on time or struggling to reach your number. Find yours with the protein calculator, and see what a 20–40g serve looks like in food on our high-protein meals pages. Wondering about creatine too? See creatine vs protein.