ChrisOmnivore, vegetarian or vegan, healthy protein is good for you.
Protein is an essential human nutrient, one of the trio that make up the ‘macronutrients’, protein, fat and carbohydrate. ‘Macro’, because these are the nutrients we need most, and ‘essential’ because they need to be included in our diets as our bodies can’t make them. Most of the vitamins and minerals we need are also essential.
Curiously and contrary to popular wisdom, carbohydrate is the non-essential third member of the trio of macro-nutrient. We can get by without it.
Protein is in fact, a chain of amino acids; there are 20 amino acids that our bodies need, primarily to build and maintain skin, muscle, bone, hair, nails etc. Nine of these amino acids are essential. So-called ‘complete’ proteins or healthy proteins are those that contain these nine essential amino acids.
Food from animals (meat, fish, dairy, eggs) is the best source of the most complete, easily absorbed proteins. Plant foods (legumes, nuts, grains, vegetables) contain incomplete and less easily absorbed proteins. However, a full suite of essential amino acids can come from eating combinations of plant protein sources. The bioavailability of proteins from plant sources can be improved through traditional methods like cooking, sprouting or fermentation or other processes such as freeze-drying, irradiation or microwaves.
So most of what your body becomes is made from the healthy protein you eat.
What do our bodies do with this healthy protein?
Protein is constantly broken down and rebuilt as your body renews and maintains itself. Some proteins make up hair, nails, skin, bones, ligaments, lungs and arteries.
Protein also takes part in many bodily functions, including your immune system. It also has a role in producing neurotransmitters and hormones, including dopamine and serotonin, feel-good chemicals. So eating more or less protein can affect your mood.
Your body has various pH values, from your blood at pH 7.4 to stomach acid at pH 2. Maintaining these values is critical to health. This is another role of protein.
Protein balances fluids in the body and is critical in the formation of antibodies to fight infection. It also has a role in transporting and storing nutrients.
The body can use Amino acids from protein to make glucose, which is important for supporting high energy demand. When dietary carbohydrates are low or have been depleted during fasting, glucose can be made from protein.
Most people know that protein is important, if not all these many functions. It is essential in our food because our bodies cannot make it and because it performs many roles beyond the obvious muscle development.
What does healthy protein consumption mean for our diet?
The generally recommended daily intake of protein (RDA) is 0.8 grams/kilo of body weight for healthy persons over the age of 19 years.
That’s about 60 grams per day of healthy protein for an 80 kilogram person, best spread across three meals a day. Although, like most RDAs, this is the minimum below which health will decline. There are no specific RDA recommendations for children, the elderly, those recovering from illness or for athletes.
As a guide, a large egg has around 6 grams of protein, a slice of cheese 7 grams and 100 gram steak has 25 grams of protein.
A fist size steak about covers the daily RDA.
Beyond the ‘official’ recommendations of 0.8g/kilo of body weight, there are various recommendations and opinions, including the idea that the calculation of the RDA only covers the body building and maintenance roles of protein, not the various other functions as detailed above, so more may be better.
Too little healthy protein may make us hungry.
The ‘Protein Leverage Hypothesis’ suggests we will feel hungry until our daily protein requirements are met. This is suggested as one reason for the obesity epidemic, eating food that is low in protein means we overeat in terms of calories to get the protein we need.
Evidence suggests that eating more protein will result in eating less overall.
Protein is essential for health. We need to get the most complete proteins in their most digestible form.
Prioritising protein could also be good to assist with controlling body weight.
Again, this is not what convention tells us.
What do the dietary guideline say?
Australia, like most countries, has published dietary guidelines. The webpage explaining them is called Eat for health, making it clear that the guidelines have a lot to do with health and prevention of disease.
The dietary guidelines for Australians prioritise grain (carbohydrate) foods over protein, suggesting that a man 51-70 years old should eat 6fist-size of grains a day and 2.5 servings of ‘lean’ protein. The recommendation for a woman of this age range is 4 of grains and 2 of protein.
This is interesting given that we know carbohydrate is a non-essential nutrient and that healthy protein, quite possibly more protein than the Recommended Daily Allowance, is essential.
Ever get the feeling that there is a mismatch here.
Guidelines say eat a non-essential macro-nutrient more than healthy protein. Vegetarians and vegans go so far as to avoid the best sources of protein altogether. Meanwhile our bodies need the stuff, lots of it.
What sustainably FED suggests…
In the 1950s in the aftermath of WW2 the Western industrial machine was unleashed on agriculture. Across Europe and North America, tractors pulled ploughs and hoes, spread fertiliser and applied pesticides across bigger and bigger fields to grow food at industrial scale. Researchers developed high-yied crop varieties and technologies were applied to the growing, harvesting, storge, transport and processing of the newly abundant crops.
Before long these developments were exported worldwide. Soon everyone was eating the industrial foods.
And what was grown?
The easiest, most cost-effective and salable crops. Turns out these were mostly grains, sugar and vegetable oils.
The newly wealthy Westerners liked their beefsteaks, so some crops were fed to animals that supplemented the herds grazing the native grasslands and pastures. Healthy protein consumption went up along with wealth but the cheapest and most accessible food was carbohydrates, the non-essential macro-nutirent.
And it still is.
Grains, sugar and vegetable oils, ultra-processed into various foods is the foundation of the Western diet, not healthy protein.
We suggest this was an unfortunate mistake.
The human body works best with healthy protein and fat as the foundation, supplemented with carbohydrates. Maybe we should build sustainable diets around protein rather than carbohydrates or kilocalories or a plant focus.
Only we cannot.
The irony of the 1950s shift to industrial agriculture and global production of carbohydrates subsidised by fossils was that it generated a lot of food. Humans ate that food and did what all organisms do with an excess of energy—they made more.
Now there are 8 billion people to feed.
Sustainably FED recognises the need for critical amino acids in diets and the healthy protein foods that provide these essentials must be present in the diet. This is easy to say but not so easy to deliver across all societies.
Useful evidence
Australian Dietary Guidelines – providing the scientific evidence for healthier Australian diets (2013)
Bohrer, Benjamin M. “Review: Nutrient Density and Nutritional Value of Meat Products and Non-Meat Foods High in Protein.” Trends in Food Science & Technology 65 (July 1, 2017): 103–12.
Noakes, M, (2018) Protein Balance: New Concepts for Protein in Weight Management; CSIRO, Australia.
Nilsson, Andreas, Diego Montiel Rojas, and Fawzi Kadi. “Impact of Meeting Different Guidelines for Protein Intake on Muscle Mass and Physical Function in Physically Active Older Women.” Nutrients 10, no. 9 (September 2018): 1156.
Nkhata, Smith G., Emmanuel Ayua, Elijah H. Kamau, and Jean-Bosco Shingiro. “Fermentation and Germination Improve Nutritional Value of Cereals and Legumes through Activation of Endogenous Enzymes.” Food Science & Nutrition 6, no. 8 (2018): 2446–58.
Pribis, Peter. “Protein Intake and Mood: A Systematic Review.” The FASEB Journal 30, no. S1 (2016): 679.10-679.10. https://doi.org/10.1096/fasebj.30.1_supplement.679.10.
Schonfeldt, Hettie, and Nicolette Hall. “Dietary Protein Quality and Malnutrition in Africa.” The British Journal of Nutrition 108 (August 1, 2012): S69–76.
Photo by Louis Hansel on Unsplash
Mark
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