The power of protein
With so many different diets and conflicting recommendations in the media, it can be difficult to establish which and how much of different foods you should and shouldn’t be eating. The information on protein is no different. There is still much debate over the best types, quantities and ratios to maintain health. Hopefully, this article will provide the knowledge to make the right choices for your own protein intake.
In unravelling the confusion over protein, perhaps the first step is to look at what it is. Protein is one of the three macronutrients your body requires, the other two being fat and carbohydrate. Protein is used by the body as the building blocks for various types of body tissue, from hair to hormones.
However, not all protein is the same. Protein is made up of units known as amino acids. There are 20 amino acids and eight of them are essential. What this means is, providing you consume sufficient levels of the essential eight, your body can manufacture the rest.
The essential aminos are valine, leucine, iso leucine, lysine, methionine, threonine, tryptophan and phenylalanine. Different amino acids are required to achieve different things and different levels are found in different foods. The main sources of protein are meats, fish, poultry, eggs, dairy, nuts, seeds and legumes, though some levels are found in virtually every food.
Protein in action
Protein is obviously important, but what does it actually do? It forms the structure as well as the functional tissue of your body with about 16 per cent of your body consisting of protein. Your tissue is constantly repairing itself, so regular protein supply is very important and even more so in those undergoing periods of growth. Don’t think this is the only role for protein, though.
Protein creates the various substances that manifest and control reactions within you. Hormones are among the most important of these controlling substances. Insulin controls blood sugar levels, thyroid stimulating hormone (TSH) impacts on blood sugar as well as metabolic speed, and epinephrine (adrenalin) controls various aspects of the fight-or-flight/stress response. Obviously, these hormones are critical to everyday functioning.
Two other “control” substances that are dependent on protein are enzymes and neurotransmitters. Enzymes regulate chemical reactions in the body and neurotransmitters are responsible for messaging in the brain.
Another vital role of protein is in the formation of antibodies that are a vital part of our immune system and protect us from pathogens such as bacteria and viruses.
So without adequate protein supply, your ability to achieve sustained energy levels, maintain a balanced mood, concentrate and fight infection are all compromised.
How much do you need?
This seems like a straightforward question but there is still a great deal of controversy over what levels of protein are optimal for good health. Certainly, different states of health and different stages of life have an impact on what levels of protein are required to keep you healthy.
Those needing greater cell repair or undergoing growth should have higher levels of protein. For this reason, sportspeople, pregnant women, children and people with some chronic illnesses need higher intakes to achieve and maintain good health but, as in all things, everyone is different.
Two people of the same age and build who do a similar level of activity may require noticeably different levels of protein. This difference can arise from external factors such as stress levels and vitamin/mineral intake, but can also simply come down to genetics. A general guideline, however, would be a minimum intake of around 1mg of protein per kilogram of bodyweight.
Unfortunately, it’s a little more complex than just eating 70g of your favourite protein source if you weigh 70kg. When looking at the level you require you need to take into account that, whatever the source, it is not 100 per cent protein. Every protein-based food will also comprise varying degrees of fats and carbohydrate. For example, 70g of lean meat will have a much greater proportion of protein than 70g of lentils.
The second factor to consider is that, not only do we require all eight essential amino acids but we need them in certain proportions. If this doesn’t occur, the tissue our body can form is limited by the essential amino acid found in the lowest level. For example, a particular food may have enough of seven of the essential amino acids to form 10 units of a particular type of tissue. But if that food only has enough of the eighth essential amino acid to form one unit, then your body will only be able to make this one unit and the excess of the other essential amino acids will be converted to energy or fat.
The amino acid that causes this reduced production is known as the “limiting amino acid”. What this means is you need to ensure you consume a combination of foods that contain sufficient levels of all the essential amino acids. This is the basis of “protein combining”.
Again, there is much debate over what ratio of amino acids humans require, but it’s generally thought that animal sources such as egg, meat, dairy and fish are closer to the ideal than the vegetarian sources of legumes, grains and nuts. This means you need to eat less of these animal sources to get the necessary level of useable protein.
Implications for vegetarians
Until recently, it was thought that to obtain a complete protein from vegetable sources (one that has sufficient levels of all essential amino acids), you needed to combine your foods in certain ways at every meal. This was because grains are lower in some aminos and higher in others, with the reverse true of legumes and nuts. It was believed that all were required in the same meal to avoid limitation (as described above).
Now, it’s widely agreed that sufficient levels of essential amino acids can be obtained from a vegetarian diet by choosing a range of grains, nuts, seeds and legumes and that the right combinations do not have to occur with every meal. Importantly for vegetarians and meat eaters alike, vegetable sources are both lower in saturated fats and often higher in vitamins and minerals and fibre. A range of protein sources is always a healthier way to go.
Foods have different amino acid combinations, but how do they get from your mouth to the formation of tissue in your body? For your body to utilise protein, it must be broken down into individual amino acids during digestion. It’s then absorbed into the bloodstream to be transported to various parts of the body where it is reassembled into whatever tissue is required at the time. If your digestion isn’t able to properly separate these building blocks, then even if you are getting a sufficient intake, you can still be protein deficient.
Protein eating tips
- Good digestion starts with your brain! The better your meal smells, looks and tastes, the higher the levels of enzymes your body will create to digest it. All the more incentive to feed yourself fabulous food and to spend the time to enjoy it.
- Don’t rush your meals or eat on the go as, not only will this reduce the digestive secretions created but often will lead to inadequate chewing. Your mum was right — you should chew your food properly. Chewing is one of the first and most important steps in the proper digestion of food, especially protein.
- Try to eat in a calm environment (without the TV on). If you are stressed or your body is in “active mode”, your blood flows away from your digestive system to your periphery and muscles. This, again, impedes good protein breakdown.
- Don’t drink too much fluid half an hour before or one hour after meals as this will dilute your digestive secretions and impede digestion.
- Eating bitter foods such as olives or bitter lettuces before your meal is a fantastic way to increase hydrochloric acid production (one of the most important enzymes for protein breakdown).
Protein and weight loss
Low-carb diets are also high-protein diets and are still in fashion for weight loss. So which is better for you — the high-protein Atkins or Zone diets, or the lower-protein, vegetarian diet? Below is a breakdown of the various schools of thought so you can be the judge. Keep in mind, though, that no one dietary plan will be suitable for every person and that finding the right balance for you is about listening to your own body. Start by paying attention to how you feel when you eat different foods.
This is probably the best-known high-protein diet and is used mainly as a weight loss program. Carbohydrates are the body’s preferred source of energy, so the theory behind Atkins is that if you limit your carbohydrate intake sufficiently and replace this with protein, your body will break down stored fat to use as energy. The second part to the theory is that consuming protein and fat sends a message to your brain that you are full much quicker than when you consume carbohydrates, thus leading to a smaller intake of food.
This program looks at higher levels of protein than in a standard Western diet but with greater carbs than with Atkins. It considers the ideal ratio of carbs, protein and fats as 40:30:30 respectively with a focus on complex carbohydrates and a healthy balance of the “good oils”: omega-3s and 6s. Its aim is less towards weight loss and more to healthy hormonal/blood sugar balance. The final goal is for sustained energy and cardiovascular health. As with Atkins, its main critics feel the recommended levels of protein and fat will lead to poor long-term cardiovascular health and cancer risk, but its supporters feel it benefits these areas.
This low-protein dietary program has certainly had a greater level of research done on it because of its place in history. As far back as 3000 BCE it was recommended as a good way to eat, by the Egyptians. It differs from the Atkins and Zone in that some people take it on for moral and ethical reasons as well as health goals. For this reason it is less prescriptive about specific protein-vs-carb levels. Because of the absence of animal and fish meats it generally contains much lower protein levels and higher carbohydrates. On a physical health level, it’s thought to be advantageous to cardiovascular health but because of the non-specific nature of the types of carbohydrates consumed, it can go either way. If a vegetarian chooses to eat large quantities of dairy and refined grains, that can have negative consequences compared with someone who eats more legumes and wholegrains.
Hartman, A et al, Paediatric neurology 2007; 35 (5): 281-292
Protein as medicine
No matter what levels or sources of protein you decide on, there is no doubt that certain amino acids can be utilised for particular therapeutic effects. Below are some of the more commonly used amino acids as well as their food sources. Remember, though: before taking supplements it’s always wise to speak to your naturopath or nutritionist.
General levels used
Anti-viral/collagen formation/calcium absorption
Chicken, fish, oats
Gut healing/improved immune function of the gut/wound healing
Cottage cheese, ricotta, oats
Liver detoxification/fat metabolism
Animal protein only
Liver detoxification/fat metabolism
Beans, eggs, garlic
Fat metabolism/energy production
Avocado, beef, milk(6)
An article on protein wouldnâ€™t be complete without some delicious (and easy) recipes to get you off the couch and into the kitchen to explore the world of protein. Bon appetit!
Banana & almond slice
3 cups almond flour (ground almond?
3 eggs, beaten
Â¼ cup coconut oil
Â½ cup honey
1 tsp baking soda
2 mashed ripe bananas
Mix all ingredients well and put into greased baking tray. Bake at 180ÂºC for approx 40 minutes (insert skewer and if itâ€™s clean on withdrawal, slice is ready).
Pumpkin & coconut soup with tender chicken
1.4L veg stock
1kg pumpkin, chopped into small pieces
2 medium onions, finely chopped
handful roughly chopped fresh coriander
1/3 of a lemon
pepper to taste
2/3 cup coconut milk
corn kernels cut from 1 corn cob
Â½ kilo chicken fillets (breast or thigh) cut into bite size pieces
Fry onions in a large saucepan with 1 tsp coconut oil on a gentle heat until soft. Add stock and pumpkin and simmer until pumpkin is tender. Blend until smooth. Over heat, add coconut milk, juice and rind from lemon, coriander and pepper to taste. Stir through until mixed. Add corn kernels. Add the chicken pieces and simmer for approx 10-15 minutes or until the chicken pieces are cooked through, then remove lemon skin. Serve with a few coriander leaves on top and with an optional dollop of natural yoghurt. Serves 6.