Difference Between Casein & Whey Protein

Casein and whey are the proteins in milk. Casein composes 80 percent, whey 20 percent. Popular among bodybuilders, casein and whey aid in the muscle-building process. Both are high-quality proteins but differ in absorption rate, effects, and advantages and disadvantages.

Absorption Rate

• Casein and whey proteins are ingested as supplements, such as powders and liquids. Casein takes longer to digest and absorb than whey. Whey is easily digested and absorbed by the body. Whey affects the muscle-building process for about an hour; casein three to four hours.

Effects

• Casein slowly increases the amino acids in blood and decreases the rate of protein breakdown. Whey results in a fast, but short-lived, spike in blood amino acids and protein synthesis, with no effect on protein breakdown.

Advantages and Disadvantages

• Casein is good for bone health because it contains dairy calcium, but can cause indigestion. Whey, in the isolate form, is good for weight control because it contains a minute amount of fat, but the fat increases in the concentrate form. Casein is suitable to take with meals and at bedtime; whey is to be taken with workouts.