Soy Protein Supplement Guide: Protein From Soy Beans
1. What is it and where does it come from?
Soy protein is a complete protein that ranks right up there with the best in the Protein Digestibility Corrected Amino Acid Score (PDCAAS). Soy protein is generally very low in or free of fat, cholesterol, and lactose.
Soy protein is approved for those who are lactose intolerant, and can be used as a meat substitute. Much more than just an ingredient for a protein shake, Soy protein can be used for cooking instead of flour, producing high protein foods that are extremely low in fat, a bodybuilder's dream come true! Soy protein is derived exclusively from soy beans.
2. What does it do and what scientific studies give evidence to support this?
Soy protein provides a healthy way to get non-animal protein into your diet. It is great tasting, natural and can have a plethora of healthy effects on the body. It is ideal for high protein/low carb diets! It's valuable constituents include saponins, phytosterols, and isoflavones. This is one of the best things about soy protein! Saponins support healthy immune system function and combine with cholesterol to reduce it's absorption into the body through the small intestine. Phytosterols have also been shown to help maintain healthy cholesterol levels.
The anabolic isoflavones in soy (genistein and daidzein), not only have exhibited effects as powerful antioxidants, but have been shown to exhibit positive health benefits for both men and women.
3. Who needs it and are there any symptoms of deficiency?
As soy is not a required nutrient, it is not associated with deficiency. However, if you don't take soy, you'll miss out on the associated benefits. Women can benefit with it the most, although men can experience the positive benefits of soy as well.
4. How much should be taken? Are there any side effects?
Soy may be safely taken in a wide range of doses. Only a very small percentage of people are allergic to soy. Be sure to consult your physician if you're on any prescription drugs, as soy may have positive or negative interactions with those drugs. Soy contains phytic acid, a compound that may interact with mineral absorption.
5. Recent Studies
December 2001 - Consuming Protein Supplements Can Help Deter the Effects of Overtraining!
Protein intake of approx. 0.88 grams per pound of body weight resulted in increased prevention of overtraining. This study was conducted at Ball State University on 17 weight-trained men. They were put on a four week "overtraining" program were they did 8-12 rep maxes for three sets, eight exercises for the first two weeks, then five sets, five exercises for 3-5 rep maxes for the next two weeks. The men were chosen to receive either an amino acid supplement or a placebo for the duration of the four weeks (0.88 grams/lb body weight/day). Those that were given the amino acids had measureable positive changes in total testosterone, the ratio of testosterone to the protein that transports it, and hemoglobin compared to those given a placebo. This proves that adequate protein consumption is the key to making gains! Be sure to get enough (approx. 1gram per lb. of body weight).
December 2001 - Protein Taken With Carbs is Better than Protein Alone for Building Muscle!
This study, conducted at University of Texas Medical Branch, measured the amount of uptake of the amino acid L-phenylalanine into healthy leg muscle tissue in one of three protein shakes. The shakes were consumed one and two hours after intense leg training and provided about 6 grams of protein, 34 grams of carbs, or both per shake for a 150 bodybuilder. The L-phenylalanine uptake in the protein and carb shake was measured as being three times higher than the carb shake and roughly twice as great as the amino shake! So, there you have it! As you know, the postworkout shake is the most critical meal for your increased anabolism. Make sure you're getting some carbs in your postworkout shake for best results!