Our bodies are composed mainly of protein, which (after water) is the most abundant substance in the body. It is the major constituent of our muscles, tissues, skin, hormones, enzymes, antibodies and blood. Even after childhood protein plays a vital role in maintaining and rebuilding our bodies as they cope with the wear and tear of daily life.
Proteins are broken down by the process of digestion into units called amino acids, and the body requires 22 amino acids to form human protein. All but nine can be produced in the body. These nine are known as 'essential amino acids' and have to be provided in the diet. Foods that contain all nine are termed 'complete proteins', and they include meat, fish, dairy and soya protein. Fruit, vegetables, grains and pulses are 'incomplete proteins' and have to be carefully combined to provide sufficient amino acids in the diet.
Protein is fundamental to rebalancing blood-sugar levels, because it encourages production of the hormone glucagon, which helps the body to release stored glycogen for energy and encourages the burning of fat. Glucagon also helps to balance excess insulin production.
What is Biological Value?
In order to be efficient, protein foods have to be of a high quality and have what is termed a high Biological Value (BV) — this indicates how much of theprotein is retained by the body. Eggs used to be classed as having the highest BY, but micro-filtered whey, whey-peptide blends and lactalbumin (whey- protein concentrate) are even higher. Micro-filtered whey protein used to be a useless by-product of cheese manufacturing. Now it is processed at very lowtemperatures and turned into a protein source with a very high BV that contains all essential and non-essential amino acids.
The only whey to go
To maintain a healthy immune system, blood, skin and muscles, you need to consume protein with a high By. Whey protein (which is derived from milk, see Q&A opposite) is an excellent supplement that has long been used by bodybuilders and athletes alike. It has many uses in a dietary regime:
¨ It encourages the formation of lean muscle mass
¨ It increases glutathione levels, which has great antioxidant and immune- boosting properties
¨ It helps to build healthy new collagen
¨ It provides an invaluable source of protein for vegetarians who are attempting to balance their diets
¨ It is a quick and easy way of having a high-protein meal or snack
¨ It can be incorporated into recipes as a replacement for carbohydrate ingredients.
There are a multitude of whey products on the market — some better than others. Many come in sweet flavours, which are great when making shakes and smoothies, but you need to source natural, unflavoured products if you want to incorporate whey-protein powder into savoury dishes such as soups. These are widely available through health-food stores and on the Web. Just make sure you don't confuse them with slimmer's meal-replacement powders, which are usually laden with carbohydrates.
The average serving of whey protein is a 25g (1 oz) scoop, but check on the label to see how much of that scoop comprises protein: the lower the protein content, the higher the carbohydrate content. And beware of `blends': these are likely to be bulked up with milk and soya derivatives. To get the best out of your whey products, go for the highest protein concentration possible.