Maintaining our body’s protein requirements is crucial for our health. Some people are a little overwhelmed with the type or amount of protein that should be consumed. Keep reading and I will explain the basics.
To start with the basics, our muscles, skin, hair, connective tissues and organs are all built from protein. We pretty much consist of protein. Further, most enzymes, hormones, antibodies, neurotransmitters and general signaling processes which are responsible for our digestion, growth, and other pathways involve protein and serve important functions.
One protein molecule consists of amino acids - AA (you can compare them with building blocks or bricks for a house). A protein is made up of 20 different AA, of which 11 are so-called “non-essential AA”. We are able to produce them ourselves. The remaining 9 AA are called “essential amino acids” which must be derived from food. Different configurations and combinations of AA result in different protein variations. (1)
Humans require high-quality proteins for protein synthesis. Generally, animal-based foods (meat, poultry, eggs, milk, milk products and seafood) provide such complete quality proteins, containing all essential AA.
Plant proteins, however, show more diverse amino acid patterns and thus sometimes lack in some essential amino acids. The lacking amino acid is termed a limiting amino acid. In legumes it would be e.g. methionine, in whole grains its lysine. The right combination of plant based food (e.g. beans and rice) results in complementary proteins, thus improving the protein quality. (1)
For easier understanding, imagine you eat a piece of meat, it includes all of the amino acids you need in order to synthesize body own protein. Easy! If you eat rice and veggies it does include protein, but not all AA you need to build protein. Thus, you should combine it with e.g. beans or other legumes to achieve the same “building” effect that meat does. Some exceptions such as soy, spirulina, hemp seeds, chia seeds, quinoa, buckwheat and amaranth do provide our body with all AA needed. (2)(3)(4)(5)(6)
For a long time, people believed that you have to eat certain combination at every meal to achieve proper protein nutrition. Nowadays, studies confirm that it is sufficient enough to consume them over the course of a day (e.g. simplified: beans in the morning and rice in the evening does the same job as combining them in one meal).
PROTEIN for VEGETARIANS - VEGANS
If you are on a vegan or vegetarian diet you need to ensure you consume a variety of foods to meet the protein requirements and all essential amino acids your body needs to build protein.
Therefore, it is crucial to eat a diversity of whole grains, legumes, seeds, vegetables, and nuts. Vegetarians can cover their protein needs sufficiently with eggs, milk and milk products. If fruits and vegetables make up the fundamental of the diet, deficiencies may occur due to a lack of protein quality and quantity.
This sounds like only animal protein is good protein. Completely wrong! Vegetarian diets are usually better in providing our bodies with essential vitamins, minerals, and fiber. Further, meat and dairy products tend to be high in saturated fats and hence linked to high blood pressure and cardiovascular diseases.
HOW MUCH DO WE NEED?
Our body continuously breaks down protein. We don't have a protein storage like the one for fat (you all know what I'm talking about) or sugar (Glycogen). Therefore, we need to consume sufficient protein to maintain body structures. Recommendations for protein vary depending on age, size, and need.
The Recommended Dietary Allowance (RDA) for protein is 0,75g protein per kg body weight for women and 0,85g protein per kg bodyweight for men (or 10-15% of the total energy). Children, infants, pregnant and lactating women, and people 70+ years of age have a slightly higher requirement. Athletes and active people are recommended to consume between 1,2-2g protein/kg BW to prevent muscle loss.
Let’s say an adult healthy woman with 65kg works out 3-4 times a week and works a job which is mostly sitting and some walking/standing.
65kg x 1,2 = 78g protein per day
78g protein per day would be the amount she has to consume in order to meet her body’s basic needs.
POSITIVE HEALTH EFFECTS
As mentioned above, protein serves as foundation for health, repayments, recovery and chemical messenger and enzymes in our body.
Protein deficiency can result in slowed growth, impaired brain and kidney functions, inadequate nutrient absorption and poor immunity.-
Protein increases fullness, satiety helps with weight loss due to reasons mentioned below. (8,9)(10)
It can increase muscle mass and strength and prevent muscle loss when losing weight. (11)(12)
Snacking and cravings might be reduced when enough protein is consumed. Studies show that late night snacking was drastic reduced when protein content in the diet was increased.
Protein consumption can boost your metabolism. To digest protein our body makes use of something called a thermic effect of food (TEF), meaning it burns calories to digest the protein. (13–16)
The risk for osteoporosis and fractures in older people is lower when adequate protein is consumed. Especially women after their menopause are recommended to consume sufficient energy together with an active lifestyle. However, excessive protein intake is associated with negative calcium balance and could potentially lead to bone loss. Therefore, dose is key! (17–19)
NEGATIVE HEALTH EFFECTS
High protein diets can also trigger several chronic diseases such as heart disease, osteoporosis, cancer, obesity, kidney stones. However, no upper level (UL) was established so far, due to insufficient data. (20) (The institute of Medicine recommended the UL for adults at no more than 30% of total energy intake)
Self-explanatory, protein excesses are more like to be caused by an over consumption of animal protein. Most of these sources contain high amounts of saturated fats which may contribute to cardiovascular diseases. To blame cardiovascular diseases on protein alone is therefore, incorrect. (21) When red meat and high-fat milk products are substituted with vegetable protein combined with low-fat milk products, fish, and poultry, cardiovascular diseases are decreased. (22,23)
Cancer and protein consumption is a popular topic. Research shows that protein itself does not seem to increase the risk of cancer, however, protein-rich foods do. As mentioned above, high intakes of red meat and processed meats and their additives are associated with cardiovascular diseases and also cancers such as colon, pancreas, and ovaries. Conversely, protein rich plants may reduce the risk of some cancers. (24–26)
Kidney diseases are often linked to excessive protein intake. A diet high in protein does not cause kidney disease, however, it increases their workload. People with chronic kidney diseases often worsen their disease by consuming too much protein. It is generally recommended to drink more water in periods where protein intake is increased.
FROM REQUIREMENTS TO GROCERIES
If you calculated your protein needs in the section above and have a number but no idea how to achieve those requirements, continue reading.
When I speak of “grams of protein” it means gram of the macronutrient protein and not grams of the protein source e.g. chicken.
Foods listed below contain significant high amounts of protein:
As you can see, it is not that hard to maintain your protein requirements throughout the day. Please keep in mind that you have higher requirements when physical activities increase.
MY TAKE ON PROTEIN POWDERS and SUPPLEMENTS
The sports and nutrition market is overloaded with protein powders and supplements. You can only get big and strong if you have a shake a day – that's what they say. I do not agree on that at all. However, protein powders may be a good alternative if there is not enough time to consume a balanced meal. By now you hopefully understand that getting enough protein is crucial to support health and muscle growth, but ingesting more than needed does not further enhance muscle function or growth. “Overdosing” with protein is very easy when consuming protein supplements. The plus is excreted by urine and will be flushed down the toilet if your kidneys are healthy. Protein powders provide amino acids to our body’s, however, protein in food sources supply the same and much more (minerals, vitamins, fiber etc.) and therefore my preferred source.
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