What are Proteins and What Do They Do?
There is a lot of hype about protein at the moment, but what do we really know about it? How much does the body need? What is the difference between animal based and vegetable based proteins? What is it made of and how important is it to get enough protein in the diet? Is a high protein diet really healthy? In this article we will try to address these questions and more...
So what is the Hype?
Proteins are the main building blocks of the body used to make muscles, tendons, organs and skin. They are also used to make enzymes, hormones, neurotransmitters and various tiny molecules that serve various functions – without protein our bodies would biochemically dismantle, life as we know it would not be possible. Amino acids are organic compounds that combine to form proteins, when proteins are digested and broken down amino acids are left. The human body uses amino acids to make proteins to assist the body to grow, break down food and repair body tissue amongst other things. The human body uses just 21 amino acids to make all the proteins it needs to function and grow, these are broken down into 3 groups:-
Essential amino acids – These cannot be made by the body and therefore must be obtained from food. There are nine essential amino acids; histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine.
Non-Essential amino acids – This means our bodies can produce these amino acids even if we don’t get them from the food we eat. These include; alanine, asparagine, aspartic acid and glutamic acid.
Conditional amino acids – These are not usually essential except for in children as they cannot make enough to meet their own needs. For adults they are only considered essential in times of illness and stress. They include; arginine, cysteine, glutamine, tyrosine, glycine, ornithine, proline and serine.
Plant Protein vs Animal Protein
"The first question I am often asked when discussing a whole-food, plant based diet is 'Where do you get your protein?'. Protein has become widely recognised as a miracle macronutrient that, apparently, is challenging to acquire in effective doses. However, this is far from accurate." - Julieanna Hever, VegNews.com
The general rule of thumb is that animal proteins tend to be “complete proteins” (they contain all 9 essential amino acids) whereas vegetable proteins tend to be “incomplete proteins” containing some but not all of the essential amino acids – however there are, as always, exceptions to the rule. For example Kale is being heralded as “the new beef”, this is due to the fact that it contains all nine essential amino acids which are actually easier to extract and digest – when consuming steak for instance, the body has to expend greater metabolic resources to break down the massive, highly complex and intricately folded protein structures. Some nutritionists argue that humans are better suited to digesting animal proteins since they are closer to our own biological make up, however, on the other side many contend that plant based proteins are healthier as animal protein tends to be higher in sulphur containing amino acids which causes increased acidity that could lead to calcium depletion as the body tries to balance out its pH level.
Another consideration when choosing animal protein is whether the meat is tainted with hormones or antibiotics, for better health benefits choose free range, grass fed, organically farmed beef or poultry.
Protein for Weight Loss
When it comes to losing weight, protein is the king of the nutrients - the importance of eating plenty of protein cannot be overstated. Protein at about 25% - 30% of calories has been shown to boost metabolism by up to 80 to 100 calories per day compared to lower protein diets. A key researcher in this area is Donald Layman Ph.D from the University of Illinois, he has written many papers on the subject. He has found that the essential amino acid leucine has an interesting effect on weight loss in that it activates a sluggish metabolism and can help to prevent muscle loss during weight loss due to its direct signalling effect on muscle mass. He noted that on a high protein, leucine rich diet that the weight lost was mainly fat whereas on a high carbohydrate weight loss diet the weight lost was mainly muscle. For example eating two eggs for breakfast has been shown to boost weight loss by 65% compared to the same amount of calories from carbohydrates like a bagel (not all calories are created the same) – in fact he also found that eating a high protein breakfast wakes up your liver (the metabolic factory of your body) and can increase your metabolic rate by 30% for up to 12 hours.
In essence, foods that are high in protein take longer to digest and metabolise and you burn up more calories trying to process them – not only that they keep you fuller for longer.
So How Much Protein Do I Need?
Current UK government guidelines for men aged 19 to 50 are 55.5g of protein per day, slightly lowering to 53.3g in those over 50. Women aged 19 to 50 are recommended 45g per day, slightly increasing to 46.5g for the over 50’s, however, one should also take into consideration the lifestyle one leads with regard to protein intake. For example, activity levels, muscle mass, current state of health and whether you are building muscle mass are all contributing factors when assessing your protein needs. Because protein is used to repair tissues, organs and many other parts of the body it would stand to reason that more protein will be needed when recovering from an accident or illness. The same goes for somebody who may lead an extremely active lifestyle – they would logically need more protein than somebody leading a more sedentary lifestyle. Also as you age and during pregnancy it is especially important to consume sufficient amounts of high quality protein as your ability to process protein declines with age, raising your protein requirements.
Can I Have Too Much?
Eating more protein than your body needs can interfere with your health. When you consume too much protein your body must remove more nitrogen waste products from your blood which stresses your kidneys. Chronic dehydration can result as was found in a study involving endurance athletes. Your goal should be a diet with enough – but not too much – high quality protein from a variety of plant and animal sources (unless following a vegan diet see below).
How Do I Calculate My Protein Requirements?
There is a simple rule to do this and all you need to know is your lean body mass, to determine this you subtract you percentage body fat from 100. For example if you have 20% body fat then you have 80% lean muscle mass – multiply that percentage (in this case 0.8) by your current weight to get your lean body mass in pounds or kilos. Dr Joseph Mercola recommends that you need half a gram of protein per pound of lean body mass – so in the above example if you weigh 140 lbs you would multiply this figure by 0.8 giving you 112 lbs of lean body mass (112 x 0.5 = 56) making your protein requirement 56 grams per day. This formula has the advantage of taking into account your actual body composition which is more relevant than age or gender.
Protein for Vegans
Contrary to popular belief it is relatively easy to get all of your amino acids as long as you eat a variety of foods – what is missing in one source will probably be present in another – however you don’t need to follow a complicated diet of combining proteins, just make sure to eat a different type of protein at every meal for example some nuts in your morning cereal, some seeds in a lunch time salad and a good helping of plant protein with your evening meal. Nature has provided us with some valuable plant based complete protein sources which can easily be incorporated into any vegan diet:-
- The Moringa Tree – the leaves contain 18 amino acids including all of the essential ones and have a protein content to rival meat. It is so nutrient dense it has been nicknamed “The Tree of Immortality” by the inhabitants of countries where it is cultivated.
- Hemp Seeds – often referred to as “nature’s most perfect food” due to their impressive amino acid profile and perfect balance of omega-3 and omega-6 fatty acids.
- Chia Seeds – a complete protein and another great source of essential fatty acids.
- Pumpkin Seeds – a rich source of amino acids, containing especially high amounts of tryptophan – the amino acid that enhances serotonin production in the body.
- Quinoa – the only grain like food that offers a complete protein, high in lysine which plays a particularly important role in the immune system.
- Chlorella/Spirulina – both are high quality complete proteins which are denser and more easily digestible than any animal-derived protein.
- Buckwheat – this is actually a fruit seed which is related to rhubarb and provides high quality, easily digestible proteins.
Protein Powders
Whilst it is always better to meet our nutritional needs from wholefoods and superfoods, if for whatever reason you don’t feel like you are getting enough protein, you can supplement your intake with an array Protein Powders now on the market – these are especially popular with bodybuilders and athletes whose protein needs tend to be higher than the average person. Here at Indigo Herbs we have an impressive range of Protein Powders which can also be blended to provide you with your optimum protein needs.
Sources for this article:-
http://www.whfoods.com/genpage.php?tname=nutrientprofile&dbid=50
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2868018/
http://miracletrees.org/moringa-doc/nutrient-content-of-moringa-oleifera-leaves.pdf
http://www.nlm.nih.gov/medlineplus/ency/article/002222.htm
http://articles.mercola.com/sites/articles/archive/2013/11/06/kale-benefits.aspx
http://nutritionstudies.org/animal-vs-plant-protein/
http://www.wellnessresources.com/tips/articles/how_protein_helps_weight_loss/
http://articles.mercola.com/sites/articles/archive/2014/09/03/too-much-protein.aspx
http://www.nutritionandmetabolism.com/content/6/1/12
http://www.ncbi.nlm.nih.gov/pubmed/19640952
http://www.ncbi.nlm.nih.gov/pubmed/11838888
http://www.ncbi.nlm.nih.gov/pubmed/20565999
http://www.webmd.com/diet/20020422/high-protein-diets-cause-dehydration
