Whey Protein
Fast-digesting dairy protein with the best amino acid profile available.
What is Whey Protein?
Whey is the liquid byproduct of cheese production. It contains all nine essential amino acids and is exceptionally rich in leucine, the primary trigger for muscle protein synthesis. It comes in three forms: concentrate (70–80% protein, some fat and lactose), isolate (90%+ protein, minimal lactose), and hydrolysate (pre-digested, faster absorption, higher cost).
What does the evidence say?
A 2012 meta-analysis by Cermak et al. in the American Journal of Clinical Nutrition, covering 22 randomised controlled trials, found protein supplementation significantly augmented gains in fat-free mass and strength during resistance training. Whey specifically outperforms casein and soy for acute muscle protein synthesis due to faster digestion and higher leucine content (Tang et al., 2009). The effect is meaningful for men over 40, who require higher protein intakes to stimulate the same anabolic response as younger men.
Multiple high-quality randomised controlled trials with consistent results and independent replication.
Dosage guide
| Effective dose | 25–40g per serving, total daily protein 1.6–2.2g per kg of bodyweight |
| Maximum dose | No upper safety limit from whey specifically: total protein intake is the relevant variable |
| Timing | Within a few hours of training. Daily total protein matters more than exact timing. |
Best form to buy
Isolate if you are lactose intolerant or want maximum protein per calorie. Concentrate is fine and cheaper for most people. Hydrolysate offers marginal extra speed at significant extra cost, not worth it for most.
Who benefits most
Anyone who struggles to hit their daily protein target from whole food. Particularly useful post-training when appetite is low.
Side effects and safety
Digestive discomfort in lactose-intolerant individuals: switch to isolate or a plant-based alternative. Some people report acne, possibly linked to dairy rather than whey specifically.
“It's food, not magic. If you're hitting 160–180g of protein per day from chicken, eggs, and fish, you probably don't need it. If you're not, a shake is the cheapest way to close the gap. Myprotein on offer is the best value in the UK by a distance.”