Whey Protein

What Is Whey Protein?

Whey protein is a byproduct of cheese production. When milk is curdled, the liquid whey is separated, filtered, and dried into powder. It contains all nine essential amino acids and is particularly high in leucine — the key amino acid that triggers muscle protein synthesis. It is one of the most popular and well-studied sports supplements on the market.

Concentrate vs Isolate vs Hydrolysate

Whey Concentrate (WPC) is the most common and affordable form. It is roughly 70-80% protein, with the remainder being fat and lactose. Good for most people.

Whey Isolate (WPI) undergoes extra filtering to remove most fat and lactose, yielding 90%+ protein. Better for those with mild lactose sensitivity and anyone wanting fewer calories per scoop.

Whey Hydrolysate (WPH) is pre-digested for faster absorption. It is the most expensive and the taste is often worse. The real-world benefit over isolate is minimal for most lifters.

How It Works

Your muscles need protein to repair and grow after training. Whey is absorbed faster than whole food sources, delivering amino acids to your muscles quickly. That said, total daily protein intake matters far more than timing. If you are hitting 1.6-2.2g of protein per kg of bodyweight from food alone, you may not need a shake at all.

What the Research Says

Whey protein supplementation consistently supports muscle protein synthesis and recovery when combined with resistance training. It is not magic — it is simply a convenient way to hit your protein target. A chicken breast does the same job; whey is just faster and easier after a session.

Who Should Take It

Anyone struggling to hit their daily protein target through whole foods. It is especially useful for people with busy schedules, smaller appetites, or higher protein requirements. One or two shakes a day can bridge the gap.

Who Should Avoid It

People with dairy allergies or severe lactose intolerance should avoid whey entirely. If you experience bloating with concentrate, try isolate first before switching to a plant-based alternative.

Vegan?

Whey protein is not vegan — it is derived from cow’s milk. If you need a plant-based alternative, look for a blended vegan protein powder (pea + rice protein provides a complete amino acid profile). Check out our vegan protein guide for recommendations.

Where to Buy

• Myprotein Impact Whey — from £16.99
• Bulk Pure Whey Protein — from £14.99
• Amazon — Optimum Nutrition Gold Standard — from £24.99

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