Whey protein is still the most popular sports supplement in the UK-and for good reason. It is convenient, well studied, and easy to fit around busy training schedules. The hard part is not whether to use whey, but which type matches your goal, digestion, and budget.
Whey concentrate vs isolate vs diet whey
Whey concentrate typically contains 70-80% protein per serving, with a small amount of carbohydrate and fat. It suits most people who want value for money and do not need ultra-low lactose.
Whey isolate is filtered further, often landing around 85-90% protein with less lactose. It is a strong choice if you want a leaner macro profile or you are sensitive to dairy.
Diet whey blends usually add fibre or thickeners and are marketed for weight management. They can work if they help you stay in a calorie deficit-but check total calories and protein per scoop, not just the front label.
What to check on the label (UK)
- Protein per 100 g - compare like for like, not just "per serving" if scoop sizes differ.
- Essential amino acids - leucine matters for muscle protein synthesis; a complete profile is ideal.
- Sweeteners and additives - tolerance varies; start with a smaller tub if you are unsure.
- Batch testing - look for Informed Sport or similar if you compete in tested sports.
How much protein do you actually need?
For most active adults, 1.6-2.2 g of protein per kg of body weight per day supports muscle gain and retention when combined with resistance training. Whey is a practical way to close the gap between meals-not a replacement for whole food.
When to take whey protein
Timing is less important than total daily protein. Post-workout shakes are fine, but breakfast, snacks, and pre-bed casein (if you use it) can all contribute. Pick a routine you will stick to for months, not days.
Shop whey protein at GymStack
Browse our whey protein range from leading UK brands including Applied Nutrition, Optimum Nutrition, and Myprotein. Filter by goal, flavour, and format to find a tub that fits your training.
Food supplements should not replace a balanced diet. Speak to a healthcare professional before starting a new supplement if you have a medical condition or take prescribed medicines.