Protein powder: whey, casein or plant — which to choose

Protein powder is not a drug or a "steroid in a bag" — it is dried milk or plant material with the protein extracted. You choose it on price, digestibility and taste, not on the picture on the tub.

The types

Whey concentrate (the most common)

70–80 % protein, the rest a little lactose and fat. The best value for money, digested quickly. If lactose does not bother you, this is the choice.

Whey isolate

85–90 % protein, almost no lactose or fat. Costs 30–50 % more. Worth it only if you are lactose intolerant or on a strict diet where every calorie counts.

Casein

Digested slowly (3–5 hours). No overnight magic, but thicker and more filling — good as an evening "pudding" or a snack.

Plant (soy, pea, rice, hemp)

Soy is closest to whey in quality. Pea and rice are often blended because their amino acid profiles complement each other. Perfectly adequate for vegans — just take 10–20 % more.

How to compare prices properly

Do not look at the price of the tub, look at the price per gram of protein:

package price ÷ (grams × % protein) = price per gram of protein

Example: a 2 kg tub for 30 € at 75 % protein = 30 ÷ 1500 = 0.02 € per gram. Compare that with chicken: 1 kg of chicken (220 g protein) for 6 € = 0.027 € per gram. Powder is often the cheaper source.

How much to take

• One scoop (25–30 g of powder) gives 20–25 g of protein.
• One or two scoops a day is plenty — the rest from food.
• If powder covers more than half your daily protein, the problem is your menu, not your powder.

What to check on the label

• Protein per 100 g — below 70 % is poor value.
• Ingredient list — protein, flavour, sweetener, emulsifier. If there are 15 ingredients and the word "matrix" in the name, you are paying for marketing.
• Amino spiking — adding glycine or taurine to inflate measured nitrogen. Rarer now, but check the protein comes from the source named.

When you do not need it

• If you already eat 1.6–2.2 g/kg from food.
• If whey bloats you and isolate is too expensive — eat yoghurt and quark instead.
• If you are a beginner who thinks powder is a requirement for results. It is not; food and training are.

The short version

• Whey concentrate for most people; isolate only for lactose issues.
• Casein in the evening if you like it thicker, plant protein for vegans (+10–20 % dose).
• Compare price per gram of protein, not per tub.
• Powder replaces a meal, it is not an extra on top of everything.