Powders, shakes and convenience
Whey isolate on a GLP-1: protein, portions and how to actually eat it
About 90 g of protein per 100 g (3.5 oz), powder, dry, representative value, for around 370 calories. One scoop, about 30 g (1.1 oz), gives roughly 27 g of protein for 111 calories.
To reach 30 g of protein from whey isolate alone you would need about 33 g (1.2 oz). On a small appetite that is often more than one sitting allows, which is why we pair it rather than chase the whole target from one food.
How whey isolate sits on a GLP-1
Whey protein isolate is about 90 g of protein per 100 g (3.5 oz), the purest protein you can buy, with the most leucine per gram of any food and very little lactose or fat. A 30 g (1 oz) scoop is about 27 g of protein for around 110 calories, in a glass, in two minutes. For someone on a GLP-1 who cannot get through a plate of food, it is the most reliable stop there is. It mixes thin and slightly watery in water, which is a virtue here: a thin drink empties faster and fills less than a thick one.
When your appetite is small
Mix it thinner than the tub says, in a small glass. One scoop in 200 ml (7 fl oz) of water or milk, shaken, drinks in a few minutes. If a whole scoop at once is too much, half a scoop twice across the morning works just as well. Unflavoured isolate also stirs into porridge, soup, yoghurt or mashed potato, which stops the flavour fatigue that makes people give up on shakes.
Three ways to prepare it
Shaken thin in water or milk
Half water, half milk if you want it creamy without being thick. Shake, drink, done. About 27 g from the scoop and 4 g more from the milk.
Stirred into porridge or yoghurt off the heat
Vanilla isolate into a small bowl of porridge once it has stopped bubbling, or into a tub of Greek yoghurt. A 30 g breakfast that is not a drink.
Unflavoured, whisked into soup or mashed potato
A scoop of unflavoured isolate whisked into a mug of pumpkin soup adds 27 g and no taste. Add it off the heat so it does not clump.
What to eat it with
Milk, a banana, coffee, oats, yoghurt or berries in a shake; soup, mash or eggs for the unflavoured version. Whey is complete on its own, so the pairing is about getting it down and making it feel like food.
How it compares
| Food | Protein per 100 g | Energy per 100 g | |
|---|---|---|---|
| Whey isolate | about 90 g | 370 kcal | this page |
| Whey concentrate | about 78 g | 400 kcal | See the page |
| Casein | about 80 g | 360 kcal | See the page |
| Plant protein blend | about 72 g | 380 kcal | See the page |
All figures are typical values for the food as eaten, powder, dry, representative value, not laboratory figures for a particular brand.
Australian, US and UK names
Whey protein isolate or WPI in all three countries. Bulk Nutrients, True Protein and Musashi are common Australian brands, MyProtein Impact Whey Isolate and Bulk in the UK, Isopure and Dymatize ISO100 in the US. Scoops vary from 25 to 35 g (0.9 to 1.2 oz), so protein per scoop ranges from about 22 to 30 g; the figures here are a representative value.
Questions people ask
Is whey isolate better than whey concentrate?
It has more protein per scoop, less lactose and less fat, and it costs more. The protein quality and the leucine per gram of protein are the same. If dairy bloats you, or you want the thinnest possible drink on a small appetite, isolate is worth the extra; otherwise concentrate does the same job.
Your number comes first
Knowing what is in a food only helps once you know how much you are aiming for. The target is 1.2 to 1.6 g of protein per kg of your goal weight, not your current weight, which for most people is 90 to 140 g a day.
Work out your protein targetMore on eating well when your appetite is small: high protein foods for a small appetite, how much protein on a GLP-1, and every food we have written up. The whole system in five documents is the Keep Muscle Kit, A$47 / US$29 / £23.
EverStrong provides nutrition and strength coaching and education. It is not medical advice and does not replace your prescribing doctor.