Whey protein is a high-quality protein that, together with casein, are the major proteins in milk. Whey protein is digested quickly, resulting in a more rapid absorption (compared to casein), & it rapidly stimulates muscle protein synthesis.
When used correctly as per the body's requirements whey has shown to increase muscle strength & enhance lean body mass and also contribute to fat loss as body's Basal Metabolic Rate (BMR) increases due to increased muscle mass. These effects may be due to the high degree of branched-chain amino acids in whey, particularly leucine.
Whey & Muscle Growth
The timing of whey protein intake is very crucial. Researches have suggested that a better time to ingest whey protein before exercise might be about 30 to 45 minutes prior in order to allow for the digestion & absorption of the amino acids.
Post workout, the major nutrient is a fast carb as your body needs to recover its glycogen stores which may be taken up by protein if carbohydrate is ignored & thus affect muscle synthesis. Whey/high quality & high biological value protein must be consumed within 20 mins of the exercise to enhance muscle protein synthesis.
Whey Protein & Weight Loss
In addition to the benefits, whey protein has on strength & muscle building, whey also has positive effects on weight loss. Protein has a satiating effect & also needs high energy to break it down into smaller units known as amino acids for absorption. Thus the BMR is greatly affected by the amount of protein in the diet & thus protein helps in bringing down fat & contribute to fat loss.
But one must remember, that anything in excess gets converted to fat in the body & if a proper balance of carbohydrate, protein, & fats is not maintained it may lead to nutritional imbalances & thus hamper the weight loss process.
See a nutritionist before self-medicating yourself.