It does not matter what type of diet you follow, Vegan, Vegetarian, Paleo, Keto, Carnivore, high carb low fat, high fat low carb, even the Standard American Diet, everyone agrees that you need protein. Sure, everyone will debate on the amount and source of the protein, but you can’t escape the fact that you need it.
Why We Need Protein?
Protein is used for a variety of functions in the body that are critical for our health and survival. When we ingest protein the body breaks it down into amino acids. Some of these amino acids cannot be made by the body and can only be found in the protein we eat. Why are amino acids important? They are used for things like making other proteins in the body, synthesizing RNA and DNA, creating dopamine, serotonin, creatine, glutathione, and nitric acid. All of these things play a critical role in our overall health. Amino acids also provide us with nitrogen, sulfer, and hydrocarbon skeletons, which cannot be made by our bodies, so we need the protein to make them.
Ok, that is a lot of sciency talk, but what do deficiencies in protein result in? Here is a list of problems that might occur when you under consume protein over a long period of time.
- Decrease in protein synthesis and increase in proteolysis in skeletal muscle and whole body
- Low serum albumin; reduced concentrations of amino acids in plasma
- Endocrine imbalance; reduced levels of insulin, growth hormone, IGF-I, and thyroid hormones in plasma
- Impaired anti-oxidative reactions; increased oxidative stress; advanced aging
- Growth stunting of the young; impaired development (including cognitive development) of the young
- Intrauterine growth restriction in maternal protein deficiency and its life-long negative consequences in postnatal growth, metabolism and health (e.g., increasing risk of obesity, infection, and cardiovascular abnormalities)
- Impairments in absorption, transport and storage of nutrients (including vitamins, minerals, amino acids, glucose, and fatty acids)
- Anemia, reduced transport of oxygen, reduced whole-body energy expenditure
- Skeletal muscle wasting; physical fatigue; weakness; headache; fainting
- Impaired immune response; frequent infections; increased rates of morbidity and mortality from infectious diseases
- Cardiac failure; cardiovascular abnormalities; hypertension
- Tissue fluid retention; peripheral and periorbital edema (particularly swelling in the abdomen, leg, hands, and feet)
- Reduced synthesis of neurotransmitters; emotional disorders (e.g., moodiness, severe depression, and anxiety); irritability; insomnia
- Loss of libido; reduced fertility; embryonic loss
- Loss of calcium and bones; dental abnormalities
- Hair breakage and loss; reduced production of pigments; appearance of grey hair color
- Pale skin; dry or flaking skin; skin atrophy
That list is not meant to scare you, and none of these things are going to happen if you under eat protein for a day, a week, or even a month. It would need to be a long time of under consuming protein to cause these problems. The point here is to illustrate the importance of consuming dietary protein.
Under eating protein long term can also result in nutritional deficiencies if you are not careful. Protein contains a lot more than just amino acids. It also contains a bunch of micronutrients, especially protein from animals, that are hard to find elsewhere. This is why vegetarians and vegans also typically need to add supplements to their diet in order to get the micronutrients they need. Animal protein contains things like folate, B vitamins, vitamin A, zinc, and iron which can be hard to find in other plant based protein sources.
Too Much Of A Good Thing?
Unfortunately, just like carbs and fat, people have been told to be careful with their protein intake, especially from animals, due to things like kidney disease and cancer.
The myth that high protein diets can cause kidney disease most likely comes from the fact that moderate to low protein diets are recommended for people who already have kidney disease. However, this does not mean that the kidney disease was caused by eating too much protein. One of the main jobs of the kidneys is to excrete excess nitrogen, and as we learned above, dietary protein is a major source of nitrogen for our bodies. Therefore, you can assume that consuming too much protein will result in more nitrogen, which will therefore put more stress on the kidneys. However, the research does not seem to back this up. The kidneys instead appear to become more efficient at their job in the presence of excess nitrogen and it does not damage them in any way. When we think about this from an ancestral point of view, if a hunter gatherer killed a Willie Mammoth they most likely ate lot of excess protein and they didn’t weigh it all out to make sure they got the right amount per day. They ate it until they were full, or none was left. The body has evolved to handle excess protein in an elegant manner. Chris Kresser’s article on this topic contains links to various studies that back this up.
On the cancer front, there have been many articles stating that eating meat causes an increase in cancer, since meat is mostly protein then the association gets made between protein and cancer. This is a little unfair because people can also get protein from plant sources, but there are no studies suggesting plat based protein causes cancer, so is it really the protein or something else?
You need to dig a little deeper into the headlines to understand more. Many studies might be based on “processed meat” consumption. As I hope many of you know, processing anything in today’s world, is generally going to make things less healthy. So you need to ask yourself, what else is in the meat these people are consuming? In addition many of these studies didn’t control for other variables. What else were these people eating? What was their lifestyle like? They could be smoking, drinking, eating fast food, etc. One thing for certain is that cancer is often a multi-factorial disease, it is usually not just one thing that causes it.
There has been one study on the protein cancer connection that was fairly well done that did control for many of the things above and does warrant some cause for concern. The study was done in mice, but it showed that mice eating a higher protein diet did have greater tumor growth than those that were on a lower protein diet. Again this was done in mice and there are some possible explanations for this. One of the amino acids in protein is methionine. Methionine is responsible for triggering the hormone IGF-1 which causes cell growth to increase. One could theorize the more methionine in the diet the more cell growth will occur. Where is methionine found? Primarily in muscle meat and eggs. However, there have been other studies shown that with proper glycine ingestion, it suppressed the IGF-1 hormone. What is glycine and where does glycine come from? Glycine is another amino acid, but unlike methionine, it is not found in muscle meat but instead the connective tissues and tendons of animals. This means that if you consume “the other bits of the animal” you would likely balance out the methionine with glycine hence keeping IGF-1 in balance. The problem today is that most people only eat the muscle meat, and eat very little in the way of the other parts of the animal.
What are some ways to get more glycine in your diet? Eat the meat of the animal from the bone and get the skin when you can. When you are eating the meat off the bone don’t be afraid of eating all that connective tissue around the joints, that is the stuff with the glycine in it! Another way to get plenty of glycine is to drink bone broth. You can make it yourself, or easily find it in most health food stores. Finally you can supplement. You can either supplement with collagen or gelatin, both of which contain glycine in high amounts, or supplement with glycine directly in pill form. Whatever method you choose I would just be sure you are getting some glycine in your diet, and preferably get it from the skin and bones, of the animal as opposed to supplementing it. (See the section below on collagen.)
How Much Protein?
Lets start with the recommended daily allowance for protein which is 0.8 grams per kilogram of body weight or 0.36 grams per pound of body weight. This represents the MINIMUM amount of protein you need to consume to be “healthy”. In my opinion this is way too low to even be considered healthy. That said, let’s put this into perspective. For someone who weighs 120 pounds, or 54 kilograms, that would be 43 grams of protein. A 6 oz chicken breast, which is not very much at all, contains about 50g of protein. My 2 year old son some probably eats this amount of protein in a day and he weighs about 20 pounds đŸ™‚
So if the RDA is low, what is the right amount to consume? In my opinion I think most people who are not obese can start with 0.6-0.8 grams of protein per pound of body weight. If you are using kilograms that would be 1.32-1.76 grams of protein per kilogram of body weight. Again, taking our 120 pound (54 kilogram) person from above, that would be anywhere between 72 and 96 grams of protein a day.
If you are obese then we will need to tweak things a bit. For example, if you weigh 400 pounds you should not be consuming 240 grams of protein a day. For obese individuals it is better to calculate your protein intake either from you target body weight, or better yet, your lean body mass. Lean body mass can be calculated by figuring out your body fat percentage, multiplying that times your body weight, and then subtracting that from your total body weight. For example, if you weigh 400 pounds and your body fat percentage is 70% you would calculate your lean body mass by doing 400 – (400 * .7) = 120. The problem with this formula is that you need to know your body fat percentage. The easiest way to figure out your body fat percentage is to use a calculator like the Navy Body Fat calculator. You could also have someone who is familiar with using body fat calipers measure you, or get something like a DEXA or BodPod done.
Special Cases
There are other special cases to consider when calculating your protein intake as well. If you are older then you more than likely need to be eating more protein.
There is increasing evidence that the current Recommended Dietary Intakes for older people of around 0.8 g/kg/day are insufficient to optimise retention of muscle mass, strength and function [31,32]. An early study by Campbell et al., found that healthy older subjects were in negative nitrogen balance after consuming the US protein RDA for 10 days [33]. Subsequent to this, a longitudinal study in older men and women aged 55 to 77 years showed that in response to a 3-month diet containing 0.8 g/kg/day protein, there was a physiological adaptation to this low-protein diet evidenced by a reduction in skeletal muscle whilst whole-body leucine metabolism was maintained [34]. These results indicate that a protein intake of 0.8 g/kg/day is not adequate to completely meet the metabolic and physiological needs of virtually all older people.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4555150/
So if you are 55 years or older the RDA is actually no longer an adequate amount to be healthy. The study above found that older people need around 1.2 grams per kilogram, or 0.54 grams per pound, of protein per day. It was also noted that protein intake alone was not enough, and that these people also had to resistance train in order to retain their muscle mass.
Another subset of people that might want to consume more protein are those who are trying to lose weight. When we are loosing weight we lose not only fat but muscle mass. The goal is to loose as much fat as possible while loosing as little muscle mass as possible. To do this you need to consume more protein than you would if you were eating at maintenance or surplus calories. So how much? This study concluded that in athletes you need 2.3 g of protein per kg of body weight to maintain muscle mass. Remember, for someone who is not in a caloric deficit the recommendation is 1.32-1.76 grams of protein per kilogram of body weight, so by these numbers, if you are in caloric deficit you could eat double the protein to maintain muscle mass! Again this was in athletes and was only a single study. I have seen some general recommendations of consuming 10-20% above what you would eat if you were eating at caloric maintenance and above. I would start there and go up if you are noticing a loss in lean body mass.
Best Sources Of Protein
So now that we have a better idea of the amount of protein we should be consuming let’s talk about where we can get protein from. By far, the best bang for your buck in terms of protein is going to be meat, fish, foul, and to some extent eggs. The reason being if you are eating pasture raised, grass fed, wild caught animals you are getting so much more than protein, you are getting a bunch of nutrients and in some cases a healthy dose of fats as well. There are many other foods that contain protein but I will let this graphic illustrate why animal protein is superior
The above graphic illustrates the problem nicely. There are certain foods other than meat that offer protein, but it is minimal when you compare it to the amount you need to eat to equal a very small 3 ounce piece of beef. If you can afford the calories that come along with consuming these non-meat sources of protein, that is OK, but most people can’t.
Protein Supplements
Protein supplements are ubiquitous at this point. I think everyone has taken a protein supplement at some point in their life. However, many people think protein supplementation is necessary, while in fact it is probably not in nearly all cases. The only situation I recommend supplementing with protein is for someone who is struggling to get in enough calories eating whole foods. If you are eating 3-4 solid meals a day and still need more calories then sure go ahead and use a supplement. Other than that protein supplements should be used strategically in “emergency” situations. For example, the most common situation for myself is when I worked out and I can’t eat a proper meal because I need to be out of the house so I will throw a couple scoops of protein powder in my water bottle and go and do what I have to do. And no, just because you have a busy day at work, it is not a good excuse to be consuming a protein supplement on the regular.
Why am I against making a protein supplement a staple in your diet? There are two main reasons. The first is that many protein supplements have been discovered to contain heavy metals in them! Protein with a side of arsenic and lead please! Check out this article from Consumer Reports. In addition protein supplements just contain protein at best, and at worst they contain a bunch of sugar and artificial ingredients. Contrast that with a piece of grass fed steak, pastured pork, pastured chicken, or wild caught fish. You are not only getting protein but a hefty dose of other nutrients as well (that most people are lacking anyways).
If you want to have a protein supplement on hand for those emergency situations the number one thing you need to look for is a certificate of analysis from a 3rd party company showing the protein is free of contaminants. The second requirement is that the protein is extracted from a reputable source. For example, for a whey protein, you want to make sure it is coming from grass-fed cows.
My personal favorite protein powder is produced by Thorne Research and is a whey protein. Thorne’s protein is NSF certified, meaning it has been tested, and is clean of anything that could be considered harmful.
If you cannot tolerate whey there are some other options as well. Egg protein powder is one option, the other option is a beef protein powder. PaleoPro has a protein powder that is a mixture of both egg and beef protein powder. However, if you cannot tolerate eggs there are just beef protein powders as well. Equip foods has a beef protein powder that you can try. The final option is to look into plant based protein powders, but most people can tolerate beef, so it shouldn’t be necessary. If for whatever reason you want to try a plan based protein powder, again Equip foods has one, or you can look at Organifi.
What’s The Deal With Collagen?
Chances are you have seen products made with collagen protein, it has become very popular as of late and for good reason. However, collagen is not a complete protein, meaning it is missing some of the essential amino acids your body needs. For that reason you should not count the protein in collagen towards your overall protein goal because it cannot be utilized by the body in the same way. Does that mean it is not important? No, it is very important. It is critical in the creating of hair, skin, nails, tendons, etc. and also helps balance levels of methionine with its high glycine content. If you are consuming 20g of collagen protein, just don’t count that towards your overall protein goal.
Branch Chain Amino Acids (BCAAs) and Essential Amino Acids (EAAs)
In addition to collagen, you may have also heard about branch chain amino acids of BCAAs. BCAA supplements contain the amino acids leucine, valine and isoleucine. These three amino acids are supposed to help prevent muscle loss while at the same time increasing muscle protein synthesis and increase power output. However, according to Ben Greenfield’s article BCAAs also have some side effects.
- High doses of BCAA’s can deplete B vitamins.
- BCAA’S can deleteriously affect serotonin levels.
- BCAA’s may cause insulin resistance and dysregulate blood glucose metabolism.
Essential Amino Acids on the other hand contain all the essential amino acids your body needs and also do not have any of these nasty side effects.
So it makes sense to take EAAs then? Only in the very rare situation. Just like with other protein supplements, it is best to get it from whole foods. Unlike, collagen, which can be tough to come by in today’s food environment, EAAs and for that matter BCAAs are present in the protein sources we all commonly eat today, so there is not reason you can’t get them from whole foods.
That said, there might be the rare occasion where they are useful. Personally, I use them as part of my race fuel strategy. They get mixed in my water flask with several other things as an easy to digest amino acid source. I only use them during longer (2 hour plus) races and training events and that is maybe a had full of times a year. I personally like the brand Perfect Amino.
Another use case might be fasting. If you are planning on doing a longer fast (24 hrs or more) and want to limit any kind of muscle loss during the fast you might think about taking these. Yes, that may not make it a strict water only fast, but it certainly would have minimal impact on anything.
Other than that, stick to whole foods and save some money on BCAAs or EAAs.
Wrap Up
- Protein is by far the most important macronutrient for your health and fitness goals.
- If someone was to track one thing, I would say it should be protein.
- The amount of protein you need is determined by your weight, age, and goals (weight loss, maintenance, muscle gain).
- Nearly your entire protein intake should come from whole food sources and not supplementation.
- There is no evidence that protein intake is associated with adverse effects on kidney or heart health, unless you have a pre-existing condition.
https://pubs.rsc.org/en/content/articlehtml/2016/fo/c5fo01530h
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