Firstly, what is protein?
Protein is a macronutrient that is essential to building muscle mass. It's made up of amino acids and also plays a vital role in repairing bones and muscles in our bodies.
Secondly, what are amino acids?
Amino acids are the monomers (a molecule that can be bonded to other identical molecules) that make up proteins. Specifically, a protein is made up of one or more linear chains of amino acids, each of which is called a polypeptide.
There are over 100 amino acids that have been found to occur naturally. Twenty amino acids are involved in making up a protein and are categorised as non-essential or essential. Non-essential amino acids are synthesised in the body, whilst essential amino acids cannot be synthesised in the body and can only be obtained through food. Essential amino acids do not need to be eaten at one meal. The balance over the whole day is more important so that there is a constant intake.
Put simply, amino acids are the building blocks of proteins, and proteins are the building blocks of muscle mass.
Now let’s discuss vegans and getting enough protein.
We often hear about the correlation between vegans and protein deficiency. Why isn’t protein consumption questioned in any other diet? I’ll tell you why. Everyone thinks plants do not provide protein and is unaware that all food is made up of a combination of proteins, fats and carbohydrates. Yes, even broccoli, carrots and chickpeas. Vegans can eat enough protein to maintain a healthy diet.
More impressive is the fact that if you're eating enough calories (energy, also expressed as kilojoules) a true protein deficiency is very rare in developed countries. So regardless of your diet it would be difficult to actually eat your way to a protein deficiency, given all foods contain some protein. And whilst I acknowledge this point I do recommend a diet that is rich in variety and quality.
So, how much protein do we need?
Protein, protein, protein. Society dictates that we need added protein in everything we eat, and more is better. Is this true? Well, protein is the building block of your muscles, skin, enzymes and hormones, and it plays an essential role in all body tissues. How much protein we actually need is often grossly overestimated.
But just how much protein is enough protein? Simply, the answer can’t be a standardised number. Each individual requires different protein needs. Whether you're an athlete, fitness enthusiast, someone who enjoys getting outdoors or a couch potato, your basic protein demands will differ.
Recently, Harvard Health Blog noted that it’s common for athletes and bodybuilders to consume extra protein to bulk up. However, the key message was that, generally, people are consuming too much protein for what their bodies demand. (REF)
Quality over quantity.
We all focus on how MUCH protein we’re consuming, whereas the focus could be placed on the QUALITY of the protein source. Everyday too many people are consuming low quality proteins through highly processed foods, inferior quality ingredients and cheap supplements. Furthermore, it is necessary to consider the make-up of a protein source; the fats, carbohydrates, vitamins, minerals, and other nutrients that come along with it. A basic guideline is to aim for nutrient rich protein sources that are low in saturated fats, processed carbohydrates and that are minimally processed. Examples of nutrient rich protein sources are beans and legumes. Black beans per 100g contain on average, 7.5 grams of protein with only 0.1g of saturated fat whilst provide soluble and insoluble fibre, great for feeling fuller for longer. Chickpeas are another great source of high protein low fat nutritionally dense food.
How do plant protein sources compare to animal-based proteins?
When comparing plant and animal protein sources it is important to consider the nutrients they provide. When people consume chicken, beef, or pork its common for the meat to be combined with other ingredients to enhance its taste and desirability. These added ingredients are often processed carbohydrates, preservatives, emulsifiers and saturated fats which all create an easier to consume, more satisfying product.
Several studies have linked red meat consumption to an increased risk of heart disease, stroke, and early death. Further studies have shown that eating more processed red meat may actually increase the risk of dying from heart disease. Processed meats include smoked meat, sausage, hot dogs, salami, bacon, and canned meat.
Animal proteins tend to be consumed as a “product” that has been far removed from a singular cut of meat. Through this process the nutrients are often lost, and you end up just consuming the food for its macronutrient content, disregarding its micronutrient quality. Sure, you’re still eating a complete protein source, but you’re eating a less nourishing food source. Attached to this food source is the added risk of disease and body damage. If you’re reading this thinking that you eat clean cuts of meat and a range of them too, this still applies. REFERENCE
Plant proteins are on average less processed and less removed from their natural state, such as vegetables, legumes and grains (not tofu, faux meats and processed products). Also, these plant protein sources boast a much higher micronutrient profile and provide us with the essential vitamins and minerals found in animal protein sources. Even better, if you eat a diverse range of plant protein sources, you’ll be receiving all the essential amino acids you need too. Oh, and without the added health risks. In fact, a plant-based diet can stop and even reverse the aforementioned health risks. Now just eating a plant based diet alone won’t help you reap these benefits. Because an unhealthy plant based diet is just as bad as any unhealthy diet. Interventional studies of plant-based diets have shown, for example, 90 percent reductions in angina attacks within just a few weeks. Further, “Only one way of eating has ever been proven to reverse heart disease in the majority of patients: a diet centered around whole plant foods. If that’s all a whole-food, plant-based diet could do— reverse our number-one killer—shouldn’t that be the default diet until proven otherwise?”
But what about B12?
Ok this term is overused and almost abused. Vitamin B12 is a water-soluble vitamin important for the maintenance of the nervous system and in the formation of red blood cells and is actually produced by BACTERIA. Yes, you heard correctly. It is not made by animals as marketing teams will have you believe.
Animals do however contain high amounts of B12 because throughout their lives they are supplemented with vitamin B12 in their food as well as being exposed to manure with some even being fed manure. So yes, animals are a source of vitamin B12 however, the FDA has reported that most meats are contaminated with faecal bacteria. Visit my B12 blog to read more. REFERENCE
But what about iron?
There are two types of iron, heme, found in animal sources only and non-heme, found in both plant and animal sources. The human body absorbs heme iron better than non-heme iron. Heme iron is also more readily absorbable by the body, meaning you have to eat more non-heme iron to get similar absorption rates. This doesn't mean that vegans don't or can't get any iron, in fact dried beans and dark green leafy vegetables are especially good sources of iron, even better on a per calorie basis than meat. My iron blog contains more information.
Foods rich in protein can have widely ranging nutritional profiles. Plant and animal sources of protein differ in terms of health benefits. For those that are looking to build muscle, recover better or are health conscious, it is recommended to consume a combination of plant-derived proteins after a workout. This can provide the body with a range of amino acids and more complete protein, as not all plant sources are complete proteins.
The take home message? Eat quality protein and adequate calories from healthy plant based sources and you'll be in the clear.
- Reece, J. B., Urry, L. A., Cain, M. L., Wasserman, S. A., Minorsky, P. V., and Jackson, R. B. (2011). Figure 5.18. Levels of protein structure. In Campbell Biology (10th ed., p. 80). San Francisco, CA: Pearson.
- Greger, (2018) Plant Based Diets, Retrieved 3rd September 2019 from https://nutritionfacts.org/topics/plant-based-diets/
- Raven, P. H., Johnson, G. B., Mason, K. A., Losos, J. B., and Singer, S. R. (2014). Proteins: Molecules with diverse structures and functions. In Biology (10th ed., AP ed., pp. 44-53. New York, NY: McGraw-Hill.
- OpenStax, Biology. OpenStax CNX. 30 Sep 2015 http://firstname.lastname@example.org.
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- Johnson, J. (21 August 2018) What is the Difference Between Animal and Plant Protein, retrieved 1 November 2019 from Medical News Today: https://www.medicalnewstoday.com/articles/322827.php