Differences Between Soy & Whey

Soy and whey are both forms of protein, available in powder form as a nutritional or sports supplement. Protein is important, particularly for athletes and bodybuilders, who use such supplements to aid recovery and promote lean muscle growth. Understand the key differences between soy and whey and make an informed choice when purchasing protein supplements.

Source

• Soy protein is extracted from the leguminous soybean plant. Whey is derived from milk, a diluted by-product of the cheese-making process.

Vitamins and Minerals

• Soy carries a significant greater vitamin and mineral profile. Soy is a good source of iron, zinc, potassium, phosphorus, vitamin E and B vitamins.

Amino Acids

• Whey is the gold standard when it comes to protein powder, and this is largely due to its well balanced amino-acid profile -- the building blocks of proteins. Soy is also a complete protein, meaning it contains all of the essential amino acids, but it isn't as balanced as whey. That said, soy contains greater amounts of glutamine and arginine, which both assist the muscle-building process.

Utilization

• Whey has a significantly higher biological value. Essentially, this means that the protein from whey is in a form more readily available to be utilized by the body. This makes it the perfect choice as a recovery or post-workout supplement, ensuring you get the nutrients you need quickly.

Hormones

• Isoflavins, found in soy, have been shown to upset hormone balance. Soy contains a phytoestrogen that could lead to a reduction in testosterone and an increase in the female hormone estrogen. In extreme cases, soy supplementation may lead to hyperthyroidism or infertility, particularly in men.

Cost

• Whey supplements are more widely used, and are in greater demand than soy products, and as such are generally more expensive.