The Story of Protein

We've all heard about protein and believe it to be an important part of our diet. But few of us understand what makes it so important and just what protein can achieve for our health, immunity and body shape. Most of us do not eat enough protein to experience the wealth of benefits it offers.

Everyone needs protein but some, like pregnant or breastfeeding mothers, those watching their weight, children, older people and the physically active, need it more than others. How much should you eat? Where can you get it from? Are all proteins the same? How much is too much? This site will answer all your questions about this wonderful life-giving substance.

What is protein?

Protein is the building block of life. It exists in every cell in the body and nutritionally alongside carbohydrate and fat as one of the three basic food requirements for human survival, let alone health, growth and body shape.

The body needs protein to make new cells, ensuring the health of skin, bone, muscle and other vital organs. Without sufficient protein, the immune system, endocrine (hormone) system, digestion and sexual health will all be compromised.

After water, protein is the most plentiful substance in the human body. It comprises 90 percent of the dry weight of blood, 80 percent of muscles and 70 percent of the skin.

Protein is made up of amino acids, some of which are made by the body, others obtainable only in the diet. If you do not eat protein at the optimum levels, your body will break down organ tissue to create the protein it needs for regeneration and repair.

The benefits

Supporting life is just the basic function of protein. A diet rich in protein sources additionally promotes:
 

• Body fat reduction
• Muscle growth and tone
• Quality skin, hair and nails
• Hormonal vitality
• Recovery from illness and injury
• Steady blood sugar
• Stronger immune system
• Stronger bones
• Enhanced mood

Types of protein

There are many foods that contain protein but only a select few supply us with the optimum amount and variety of amino acids we need.

Of the 20 primary amino acids, eight are necessary for human survival and must be obtained nutritionally*. These are known as essential amino acids. The other 12 are non-essential amino acids which the body can synthesise if it doesn't obtain them from food.

Foods that contain all eight essential amino acids in their correct proportions to support health and growth are known as complete proteins. Meat, fish, poultry, eggs, dairy foods, whey-protein based powders and soy protein isolate are complete proteins. To reap the benefits, you must include complete protein at every meal. Very few people enjoy roast lamb in the morning and most are too cholesterol-conscious to eat eggs every day, but you can ensure that you receive complete protein at breakfast by including protein bars, drinks or powders.

Partially complete proteins are those that contain the eight essential amino acids but not in the appropriate proportions to support optimum health and growth. Examples are peas, beans, rice, nuts and grains.

Incomplete proteins have one or more essential amino acids missing and, consumed by themselves, do not wholly support life, health or growth. Examples are most fruits and vegetables. Both incomplete and partially complete proteins can be matched with other foods to make complete proteins but this requires complex food matching.

Where can I find it?

The following are the best sources of complete protein:

þ Whey Protein Concentrate
þ Whey Protein Isolate
þ Eggs
þ Poultry (chicken breast and turkey)
þ Fish
þ Beef
þ Cheese (especially cottage cheese and ricotta)
 
If you are vegetarian, protein drinks and bars boosted with whey or soy-based proteins offer a non-meat source of complete protein. Without the convenience of these, the following foods must be matched to make a complete protein:

þ Grains with legumes (eg, rice and beans)
þ Grains with nuts/seeds (eg, bread and peanut butter)
þ Legumes with nuts/seeds (eg, hummus -chickpeas and sesame paste)

How much protein do I need?

The Recommended Dietary Intake (RDI) for protein is currently one gram per kilogram of body weight. This is a conservative estimate which Australia's National Medical Health and Research Council has based on the nutritional needs of sedentary (inactive) individuals to prevent malnutrition. In other words, their recommendation is the amount of protein you need just to survive. But not every body is sedentary.

Those who are highly active require at least 1.4g per kg body weight because muscle tissues need this extra protein to repair. When pregnant or breast-feeding, the RDI also increases to 1.4g per kg because the developing foetus requires protein, as does the production of breast milk. Our need for protein also increases as we get older to support bone health and muscle tissue.

Can I over-eat protein?

From time to time, cautionary articles arise implying health concerns resulting from protein usage. One frequent media bogey suggests that protein may contribute to compromised kidney function. There is not one piece of scientific literature to suggest that a protein intake up to two to three times the RDI, consumed by people with healthy kidneys, places any adverse pressure on the organs. In fact a number of studies conclude that eating anything up to three times the RDI has no harmful effect on the kidneys or liver. Much of the misinformation stems from studies involving subjects who had compromised kidney function before increasing their protein intake. If you have any concerns about the health of your kidneys prior to changing your diet, consult your doctor.

Can I under-eat protein?

Absolutely. Many women, in particular, under-eat protein in trying to maintain a low-fat diet. In cutting out fats, you also sacrifice protein because both protein and fat tend to co-exist in foods such as meats, eggs and dairy.

Does increasing my protein mean I'm on a high protein diet?

"High" needs qualification. Some people think that by simply increasing their protein intake they are going on a high protein diet. But the majority of people in the modern industrialised world live on a high carbohydrate, and therefore unbalanced, diet, making grains, starchy vegetables and other sugars the basis of each meal or snack. This over-consumption of carbs leaves the diet wanting for moderate amounts of protein and healthy fats. In these instances, elevating your protein intake and reducing your carb intake simply balances the diet.

Don't I get all my protein requirements from meat?

Using protein supplements offers four main advantages:

1.              Quality (added health benefits and usage)
2.              Convenience
3.              Value for money
4.              Versatility (as a cooking ingredient in both sweet and savoury foods)

Meat, eggs and dairy do not provide the same level of quality that whey and soy protein-enriched powders and snacks do. There are four main ways these protein-enriched foods have the edge: ease of digestion, rapidity of assimilation (especially important for strength athletes), completeness of absorption and utilisation, and the delivery of bonus health benefits missing in other foods.

Protein is difficult to obtain at RDI level let alone when you need extra for weight management, an active lifestyle or early motherhood. You need protein at every meal to receive maximum benefit. However it is difficult to incorporate protein at every meal. The same applies to eating on the run or snacking during the day. This is where protein supplementation comes in. Eating a protein bar or whipping up a quick protein shake or smoothie offers great convenience.

Proteins such as whey protein concentrate, whey protein isolate and soy protein isolate rank the highest above all foods when it comes to ease and rapidity of digestion as well as utilisation. To get the equivalent amount of useable protein from whole foods, you would have to eat at least 15 percent more of those foods.

Interpreting the Nutritional Panel

When shopping for foods, you can normally check the nutritional information panel on a food product to find out how much of each ingredient you are getting per serve. But the protein count on the nutritional panel can be deceptive.

Just as protein foods can vary in amino acid content, proteins can also vary in useability. For example, a box of wheat-based breakfast cereal may claim to contain 11g protein per serve, but unfortunately only 25 percent of wheat protein is used in the body's repair processes compared to 100 percent of protein in an egg, chicken breast or protein shake. So that comes to just under 3g useable protein you are getting from your cereal.

The currently accepted scoring method in the scientific community is PDCAAS (Protein Digestibility Corrected Amino Acid Score). The PDCAAS is a multiplier to keep in mind when referring to the nutritional panel for the protein content of a food product. It calculates the useable amount of protein. The PDCAAS for lentils is 0.52 so a cup of cooked lentils, containing 17.8g of protein is 9.25g (17.8 multiplied by 0.52).

Only dairy foods, meat, eggs and some soy foods are given the highest PDCAAS of 1.0. Protein powders conveniently and economically deliver maximum-PDCAAS protein if they contain whey protein concentrate, whey protein isolate or soy protein isolate.

Use this general guideline to calculate the true protein content of a food product and make better sense of the nutritional panel.   

Protein for weight loss

Increasing your protein intake assists weight management in three important ways.

1. By naturally satisfying appetite and preventing cravings
2. By lessening the impact of insulin and its effect on weight gain
3. By maintaining metabolism, ensuring you do not lose vital tissue like muscle.

There are many popular approaches to weight management: from reducing carbohydrates to eating low fat to simply eating less. But to get the results you want from these diets, you will need to contend with one common obstacle: hunger. Unless you are satisfied at every meal, you will crave foods that sabotage your weight loss efforts and make it harder for you to stick to your plan. The more "light and healthy" you eat, the greater the reduction in satiety. There is no point enjoying a garden salad or cheese sandwich in your lunch break if you are going to reach for biscuits, chips or cake come mid-afternoon.

The only way to nail satiety is to increase your protein at both snack time and meal time. Protein sends a chemical messenger (cholecystokinin) to the brain telling it you are satisfied. You will crave less, feel great and stick to your diet more easily. Best of all, by reducing your cravings, protein will help ensure your kilojoule input (food) does not exceed your kilojoule output (energy) - a critical factor in weight management.

Protein also keeps your blood sugar stable which is important for weight control. When you eat a meal or snack high in carbohydrates, blood sugar levels increase and your body responds by secreting the hormone insulin. Insulin stores unused sugar as body fat. Protein slows the entry rate of sugars into the bloodstream and reduces the weight-gaining impact of insulin.

Finally, protein helps you maintain metabolism. This process describes the build-up and break-down that occurs during the body's production of energy. By preventing the break-down of vital organs and tissue, especially muscle, protein ensures you make more efficient use of all the food you eat for energy rather than padding.

Protein for building muscle

Protein is essential for lean muscle gains, but it does not achieve this growth all by itself. It works in tandem with strenuous physical activity, such as weight training and other strength sports. These activities literally damage the muscle tissue on a cellular level, prompting the need for repair so that muscles grow back bigger and stronger. Protein is the vital building block called on to make these repairs and stimulate growth.

This period, when the body repairs itself after exertion, is known as recovery. A common objective for bodybuilders is to shorten recovery time so that training can be increased and growth fast-tracked. The inclusion of sufficient dietary protein at every meal helps shorten recovery time.

Protein is unique for its nitrogen content. The body needs this nitrogen to synthesise the amino acids and internal proteins specifically required for muscle tissue. Strength athletes commonly aim for positive nitrogen balance where the amount excreted (in urine) is less than that ingested - an indication that protein is being utilised for tissue building. To keep the body in positive nitrogen balance, it is recommended that protein be present at every meal, and five or six small meals be consumed each day.

If there is insufficient protein in the diet, the body goes into negative nitrogen balance, extra time is lost waiting for muscles to recover, quality of muscle repair is compromised, and muscles can even give up their protein content for the maintenance of other vital organs. The heart, liver, bones and skin, for example, all take priority when protein is distributed and utilised. Muscles are of lesser priority since not all muscles are engaged during the course of daily activities. Therefore, extra protein in the diet - at every meal - is essential for those aiming for lean muscle gains.

Protein for convalescing patients

Illness and injury take a nutritional toll on the body. People who have had major surgery have an increased requirement for protein, among other nutrients, for repair and recovery. Extra protein can also assist in reducing the wasting of body mass in patients such as those fighting cancer and HIV/AIDS.

Protein for people with immune deficiency

Protein is an important contributor to the immune system, making the antibodies that counter disease on a molecular level. Some protein sources, such as Whey Protein Concentrate, additionally offer two powerful forms of support. WPC is a rich source of immunoglobulins (clusters of antibodies) and cystine, a superior delivery molecule for cysteine which is essential for making glutathione, the body's most powerful antioxidant and first line of defence against disease.

Protein for older people

The Australian RDI for protein is higher as we age. Along with calcium, protein is vital for building strong bones. The Framingham Osteoporosis study in the US* - one of the longest-running health studies in the world - looked at protein intake in older men and women and showed a clear association between low protein intake and increased bone loss.

In advanced years, our sensory appreciation of food declines, chewing becomes more difficult and many are less able to prepare meals. Foods such as Protein Whip icecream offer easy-to-digest, delicious and convenient ways to ensure protein nutrition.

Protein for pregnant mothers

During pregnancy the need for dietary protein increases because the foetus requires high amounts of protein for optimum development. During breastfeeding, protein intake must be similarly increased to support the formation of quality breast milk.

Protein for Vegetarians and Vegans

Vegetarians and vegans face two challenges in balanced nutrition: consuming the right amount of protein each day and getting protein in its proper form - as complete protein which the body needs for optimum health. Fruit, vegetables, grains and legumes are all highly nutritious but without the right balance of amino acids, there is high risk of blood sugar fluctuations, weight gain, depression, poor skin quality and bone density, and weakened immunity.

Protein for people with food intolerances

The two main allergens in dairy foods are casein and lactose. In formulations such as Whey Protein Concentrate and Whey Protein Isolate, casein is removed and lactose reduced to tolerable levels. These protein sources offer all the major benefits of a dairy-based protein - including calcium and quality complete proteins - without the allergens.

Protein for diabetics

Protein lowers the Glycemic Load of a meal, which is an important factor in the management of diabetes. Foods are assigned a Glycemic Index (GI) measuring their ability to raise blood glucose levels and, in turn, trigger insulin secretion. Glycemic Load is the total GI of a complete meal. Proteins (along with fats) contribute no sugar to the bloodstream and therefore lower the Glycemic Load, reducing demand on insulin and ensuring the health of diabetics.

"While many nutritionists condemn low-carb dieting, the strategy of weight-loss through reducing refined carbohydrates (especially sugar) and increasing protein is scientifically sound. By reducing carbohydrates we stabilise our blood sugar levels which discourages fat storage and protein has been proven to reduce hunger and boost metabolism.