Is there lactose in whey protein?
Depends — concentrate high, isolate low.
Whey protein comes from milk, so it can contain lactose — but it depends on the type. Whey concentrate holds more; whey isolate is filtered further and has much less; and there are lactose-free and plant options too.
This is the one gym-goers ask about constantly, usually after a rough post-workout shake. Whey is a milk derivative, so lactose comes along for the ride — but how much depends entirely on which whey you bought.
Whey concentrate is the cheaper, less-processed form and retains more lactose. Whey isolate is filtered to remove most of the carbs and fat, and much of the lactose with them, so it’s usually far gentler. Whey hydrolysate is gentler still.
The fix: if your protein shake reliably bloats you, don’t give up on protein — just switch from concentrate to isolate, or to a lactose-free or plant-based powder. It’s often that simple.
How much lactose is in whey protein?
It splits sharply by type. Whey concentrate holds roughly 4–8 g per 100 g (about 1.2–2.4 g in a 30 g scoop); whey isolate is filtered down to ~0.5–1 g per 100 g (about 0.2–0.3 g a scoop). At two scoops a day, concentrate can be enough to trigger symptoms, while isolate and lactose-free powders rarely bother most people.
| Food | Lactose per 100 g | Per 30 g scoop |
|---|---|---|
| Whey protein concentrate | 4–8 g | ~1.2–2.4 g |
| Whey protein isolate | 0.5–1 g | ~0.2–0.3 g |
| Plant protein (pea, rice) | 0 g | 0 g |
Figures from manufacturer and industry data (vary by processing grade) — full lactose chart & sources.
When to take a little care
Read the tub: “whey protein concentrate” high on the ingredients list means more lactose. Look for “isolate,” “lactose-free,” or a plant protein if you react.
If whey protein isn't handy, reach for…
Common questions
Can lactose-intolerant people take whey protein?
Is whey isolate lactose-free?
What protein powder is best for lactose intolerance?
Want the full picture? Grab our free Living Lactose-Free in Australia cheat sheet — it sorts 60+ foods like this one so you never have to guess at the supermarket again.