Summary

The Importance of Protein

Today’s advertising makes it difficult to ensure we’re providing our bodies with the best available nutrients – protein included. Every cell in your body is about 50 per cent protein, making it the second most abundant nutrient in the body, water being first. The primary function of protein is to build and repair body tissues. Once ingested, protein goes to work building and repairing your muscles, blood, skin, hair, nails and internal organs. Symptoms of protein deficiency include loss of stamina, mental depression, weakness, and weakened immune function, thus slow healing and recovery from injury, illness and disease.

Bioavailability of Common Protein Sources

Bioavailability is the extent to which a nutrient can be used by the body. “Biological Value” (BV) is the best determinant of how efficiently the human body uses protein. Other measures that appear periodically include the Protein Digestibility Corrected Amino Acid Score (PDCAAS), expressed as a percentage. When this measure was developed, eggs were the highest valued protein at 100%. With the development of whey proteins at higher values, eggs and whey still measure at 100% on this scale, so consider this scale outdated. The Protein Efficiency Ratio (PER) is based on the evaluation of the growth of animals consuming dietary proteins. Obviously, BV is the most relevant measure for determining nutrient value for the human body.

The following table compares the value of common protein sources.

Table 1. Protein Quality Comparison[1]

Protein Source	BV
Whey protein Whole eggs Egg white (albumin) Fish Beef Chicken Casein Soy Protein Concentrate Wheat Gluten Beans (in general)	100-159 88-100 88 83 80 79 80 74 54 49

How Much of What Kind of Protein?

Different people require different amounts of protein depending upon activity and stress levels, fitness goals, and individual metabolism. Reference our comparison to fuel your body with the sources that best meet your health goals and lifestyle.

Elite athletes often select premium whey isolate to obtain nutrient-dense fueling without excess calories from carbohydrates and fat. Extremely active people place great demands on bodily tissues, so require more protein for adequate repair. Again, whey protein provides a wise choice. People who watch their weight, who have trouble getting enough protein, or who seek a quick, balanced meal will also find a whey protein shake an easy, smart option. Remember, the lower the BV, the greater the waste product put off by the body, including gas! Choose a variety of higher quality proteins for optimum health.

The table makes it easy to identify the higher quality sources of traditional protein such as meat, fish, dairy, and vegetables. For healthy nutrition, remove any visible fat and prepare your entrée adding little or no oil. Limit beef and egg yolks to control cholesterol. However, selecting quality whey proteins is more challenging -- notice the broad BV range.

How to Find Quality Whey Protein

Whey proteins are not all the same. Different formulations and manufacturing processes impact BV. Astute protein-shoppers select whey peptide blends and avoid inferior denatured whey protein concentrates. The integrity of the protein molecule is protected by ion-exchange or cross-flow membrane extraction methods, providing sustained increases in glutathione -- a critical antioxidant for muscular strength and strong immunity.[2-4] Look for the terms whey protein isolate, whey peptide blends, ion-exchange and cross-flow membrane extraction.

Benefits of Premium Protein Consumption

Countless scientific studies show many health benefits from incorporating high BV whey protein isolate into your daily nutrition plan. If you feel it’s important to boost cardiovascular health, maintain bone density or slow bone loss,[5] maintain lean muscle mass[6] (muscle itself is a source of glutamine), reduce stress or enhance mood,[7] then consider adding this important supplement to your diet. If that’s not enough, a host of studies strongly indicate that quality whey protein isolates boost the immune system, thus increasing resistance to various infections, diseases and cancers[8-10]

If you have special needs, quality whey protein formulations may be just what you need to provide your body with adequate protein. Pregnant women and children can use high quality whey protein isolate products, providing they have no dairy allergies. (Pregnant women should first check with their health care provider.) Quality whey proteins provide a great protein source for people with digestive problems or lactose intolerance since whey protein isolates contain less than 1% lactose. If you’re allergic to dairy products, find out if casein, whey or both proteins cause the reaction. If you’re sensitive to casein, whey isolates provide a practical alternative. Lacto-ovo, lacto, and ovo vegetarians find whey protein isolate a viable option. Many vegetarians suffer from protein deficiency, as do many elderly people, who can also benefit from protein-rich food sources.

Whey proteins can be a valuable part of a weight loss program as it provides a high quality, low fat, and low carbohydrate source of protein. By preserving or building lean muscle mass, you’ll maintain or increase your body’s ability to burn fat. Components of whey proteins help satiate the appetite by increasing cholecystokinin (CCK), an appetite-suppressing hormone.[11]

Athletes and active people find quality whey formulations to be complete sources of protein, providing a rich source of branched chain and essential amino acids. Adequate protein intake ensures repair of lean muscle tissue that has been broken down by exercise.